subject:(pNIPAm)

1. Lang, Xiaolong. Structural and Chemical Contributions to Poly (N-alkyl acrylamide) Responsiveness.

Degree: PhD, Macromolecular Science and Engineering, 2019, Case Western Reserve University School of Graduate Studies

URL: http://rave.ohiolink.edu/etdc/view?acc_num=case1548428317696918

► Poly (alkyl acrylamide)s, most notably poly(N-isopropylacrylamide) (PNIPAM), are widely studied thermoresponsive polymers. Many undergo a coil to globule transition when heated above their lower critical… (more)

▼ Poly (alkyl acrylamide)s, most notably poly(N-isopropylacrylamide) (PNIPAM), are widely studied thermoresponsive polymers. Many undergo a coil to globule transition when heated above their lower critical solution temperature (LCST), and several exhibit cononsolvency behavior in mixtures of water and alcohol. Cononsolvency is a phenomenon in which a mixture of two solvents, each of which can individually dissolve a polymer, results in a poor solvent for that polymer. PNIPAM, and other thermoresponsive polymers, are attractive due to the ability to tune thermoresponsive properties, such as the critical temperature and polymer conformation, by controlling the polymer architecture. In order to study the structure-property relationships of PNIPAM and other similar poly(N-alkylacrylamide)s, low dispersity star PNIPAM and linear poly(N-alkylacrylamide)s with various terminal groups – including bromine, phenyl, dodecyl, ethyl, and hydroxyl – were synthesized via RAFT and ATRP polymerization. One pot aminolysis/thiolene chemistry was used for post-polymerization modification of terminal groups. The influence of terminal group, polymer architecture, monomer structure and alcohol structure on cononsolvency, assembly, and thermoresponsive behavior of poly (N-alkylacrylamide)s in solution was determined with a combination of small angle neutron scattering (SANS), turbidimetry measurements, dynamic light scattering, and dissipative particle dynamics (DPD) simulations. SANS measurements show that both the number of arms (f) and terminal group play a dominant role in the solution behavior of PNIPAM in relation to the interaction parameters, conformation of the arms of the polymer, and clustering/association of the polymers below the LCST. Large scale, fractal assemblies (larger than 1 μm) are observed below the critical temperature for polymers terminated with short hydrophobic groups, but for long hydrophobic terminal groups, polymers formed small micelles (ca. 15 nm). The size and shape of the non-polar, hydrophobic region of both the solvent molecules and the substitute group of poly(N-alkylacrylamides) influence hydrophobic hydration, which affects critical solution temperature (T_C) and the phase transition behavior. These results indicate that, despite making up only a small fraction of the polymer, the terminal groups play a large role in both the conformation and assembly of PNIPAM and its analogs below the critical temperature, and hint at the possibility of new design strategies for thermoresponsive materials. Advisors/Committee Members: Hore, Michael (Advisor).

Subjects/Keywords: Polymers; LCST, Thermoresponsive; PNIPAM

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APA (6^th Edition):

Lang, X. (2019). Structural and Chemical Contributions to Poly (N-alkyl acrylamide) Responsiveness. (Doctoral Dissertation). Case Western Reserve University School of Graduate Studies. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=case1548428317696918

Chicago Manual of Style (16^th Edition):

Lang, Xiaolong. “Structural and Chemical Contributions to Poly (N-alkyl acrylamide) Responsiveness.” 2019. Doctoral Dissertation, Case Western Reserve University School of Graduate Studies. Accessed April 13, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=case1548428317696918.

MLA Handbook (7^th Edition):

Lang, Xiaolong. “Structural and Chemical Contributions to Poly (N-alkyl acrylamide) Responsiveness.” 2019. Web. 13 Apr 2021.

Vancouver:

Lang X. Structural and Chemical Contributions to Poly (N-alkyl acrylamide) Responsiveness. [Internet] [Doctoral dissertation]. Case Western Reserve University School of Graduate Studies; 2019. [cited 2021 Apr 13]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=case1548428317696918.

Council of Science Editors:

Lang X. Structural and Chemical Contributions to Poly (N-alkyl acrylamide) Responsiveness. [Doctoral Dissertation]. Case Western Reserve University School of Graduate Studies; 2019. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=case1548428317696918

2. Vialar, Pierre. Propriétés mécaniques et nanotribologiques de monocouches auto-assemblées de microgels de poly(NIPAM) cationique en milieux aqueux : Mechanical and lubricant properties of self-assembled layers of poly(NIPAM)-based cationic microgels in water.

Degree: Docteur es, Polymères, 2018, Bordeaux; Université de Montréal

URL: http://www.theses.fr/2018BORD0225

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Le but de cette thèse est de faire évoluer les connaissances et la compréhension des systèmes lubrifiants en milieux aqueux, synthétiques comme biologiques. Pour cela,… (more)

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Le but de cette thèse est de faire évoluer les connaissances et la compréhension des systèmes lubrifiants en milieux aqueux, synthétiques comme biologiques. Pour cela, nous élaborons des systèmes de monocouches auto-assemblées de microgels thermosensibles de pNIPAM cationiques afin d’en étudier les propriétés mécaniques et nanotribologiques. Nous mettons au point plusieurs synthèses de microgels afin d’étudier l’effet de l’élasticité sur le comportement tribologique. Nous regardons également l’effet de la nature du greffage des microgels en sur-face, en élaborant une méthode de couplage chimique novatrice, pour comparer les propriétés de monocouches physi- et chimisorbées. Nous étudions les propriétés mécaniques en mi-lieux aqueux des couches des différents microgels en fonction de la température, de la nature du greffage et du sel en présence, à l’aide d’une Microbalance à Cristal de Quartz avec mesure de Dissipation (QCM-D). Le coeur de notre étude est réalisé à l’aide d’un Appareil de Forces de Surface (SFA) modifié pour permettre des mesures tribologiques, dont les résultats seront traités en deux parties. La première consiste à caractériser les forces normales de surface lors-que l’on comprime deux surfaces décorées de microgels. La seconde est constituée de l’ana-lyse de ces surfaces sous compression et cisaillement. Nous explorons les propriétés lubrifiantes du système et observons l’apparition une force de normale dépendant de la vitesse de cisaillement, et dont nous cherchons l’origine. Nous avons ainsi découvert un mécanisme propre au substrat souple, décoré de particules discrètes avec un contact répulsif sans friction à longue portée.

The aim of this project is to advance the knowledge and understanding of lubricating systems, whether synthetic or biological, in aqueous media. For this purpose, we develop self-assem-bled monolayer 2D-arrays of cationic pNIPAM thermosensitive microgels in order to study their mechanical and nanotribological properties. We establish several synthetic routes to modulate the microgel rigidity and study its effect on the tribological behaviour. We also look at the effect of the grafting nature of microgels on the substrate, by developing an innovative chemical coupling method, to compare the properties of physisorbed and chemisorbed mon-olayers. We probe the mechanical properties of the microgel layers in aqueous environment while varying the temperature, the nature of the grafting and the salts added to the system, primarily by using a Quartz Crystal Microbalance with Dissipation monitoring (QCM-D). The core of our study is performed using a modified Surface Forces Apparatus (SFA) which allows for tribological measurements, the results of which will be treated in two parts. First, we char-acterise the normal surface forces when compressing two surfaces decorated with the micro-gel layers. Second, we study the behaviour of these surfaces under compression and shear. We explore their lubricant properties and observe the appearance of a shear-induced velocity-dependent lift…

Advisors/Committee Members: Drummond, Carlos (thesis director), Giasson, Suzanne (thesis director).

Subjects/Keywords: Hydrogels; Microgels; Surfaces; Nanotribologie; PNIPAM; Hydrogels; Microgels; Surfaces; Nanotribology; PNIPAM

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APA (6^th Edition):

Vialar, P. (2018). Propriétés mécaniques et nanotribologiques de monocouches auto-assemblées de microgels de poly(NIPAM) cationique en milieux aqueux : Mechanical and lubricant properties of self-assembled layers of poly(NIPAM)-based cationic microgels in water. (Doctoral Dissertation). Bordeaux; Université de Montréal. Retrieved from http://www.theses.fr/2018BORD0225

Chicago Manual of Style (16^th Edition):

Vialar, Pierre. “Propriétés mécaniques et nanotribologiques de monocouches auto-assemblées de microgels de poly(NIPAM) cationique en milieux aqueux : Mechanical and lubricant properties of self-assembled layers of poly(NIPAM)-based cationic microgels in water.” 2018. Doctoral Dissertation, Bordeaux; Université de Montréal. Accessed April 13, 2021. http://www.theses.fr/2018BORD0225.

MLA Handbook (7^th Edition):

Vialar, Pierre. “Propriétés mécaniques et nanotribologiques de monocouches auto-assemblées de microgels de poly(NIPAM) cationique en milieux aqueux : Mechanical and lubricant properties of self-assembled layers of poly(NIPAM)-based cationic microgels in water.” 2018. Web. 13 Apr 2021.

Vancouver:

Vialar P. Propriétés mécaniques et nanotribologiques de monocouches auto-assemblées de microgels de poly(NIPAM) cationique en milieux aqueux : Mechanical and lubricant properties of self-assembled layers of poly(NIPAM)-based cationic microgels in water. [Internet] [Doctoral dissertation]. Bordeaux; Université de Montréal; 2018. [cited 2021 Apr 13]. Available from: http://www.theses.fr/2018BORD0225.

Council of Science Editors:

Vialar P. Propriétés mécaniques et nanotribologiques de monocouches auto-assemblées de microgels de poly(NIPAM) cationique en milieux aqueux : Mechanical and lubricant properties of self-assembled layers of poly(NIPAM)-based cationic microgels in water. [Doctoral Dissertation]. Bordeaux; Université de Montréal; 2018. Available from: http://www.theses.fr/2018BORD0225

University of Georgia

3. Giasuddin, Abul Bashar Mohammad. Selective growth of thermo-responsive polymer brushes through orthogonal self-assembly.

Degree: 2014, University of Georgia

URL: http://hdl.handle.net/10724/27460

► In this work, thermally responsive poly(N-isopropyl acrylamide) or p(NIPAM) brushes were successfully grafted to multi-component surfaces with chemical selectivity. A catechol based photo-initiator was synthesized… (more)

Subjects/Keywords: polymer brushes; pNIPAM; orthogonal self-assembly

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APA (6^th Edition):

Giasuddin, A. B. M. (2014). Selective growth of thermo-responsive polymer brushes through orthogonal self-assembly. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/27460

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Giasuddin, Abul Bashar Mohammad. “Selective growth of thermo-responsive polymer brushes through orthogonal self-assembly.” 2014. Thesis, University of Georgia. Accessed April 13, 2021. http://hdl.handle.net/10724/27460.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Giasuddin, Abul Bashar Mohammad. “Selective growth of thermo-responsive polymer brushes through orthogonal self-assembly.” 2014. Web. 13 Apr 2021.

Vancouver:

Giasuddin ABM. Selective growth of thermo-responsive polymer brushes through orthogonal self-assembly. [Internet] [Thesis]. University of Georgia; 2014. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/10724/27460.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Giasuddin ABM. Selective growth of thermo-responsive polymer brushes through orthogonal self-assembly. [Thesis]. University of Georgia; 2014. Available from: http://hdl.handle.net/10724/27460

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Melbourne

4. Jaber, Sarah. Synthesis and self-assembly of core-shell gold nanorod-PNIPAM nanoparticles.

Degree: 2016, University of Melbourne

URL: http://hdl.handle.net/11343/113708

► An essential requirement for the use of nanoparticles in self assembly applications is ensuring their colloidal stability is maintained, as well as being able to… (more)

Subjects/Keywords: Gold nanorods; PNIPAM; core-shell microgels; assembly

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Jaber, S. (2016). Synthesis and self-assembly of core-shell gold nanorod-PNIPAM nanoparticles. (Doctoral Dissertation). University of Melbourne. Retrieved from http://hdl.handle.net/11343/113708

Chicago Manual of Style (16^th Edition):

Jaber, Sarah. “Synthesis and self-assembly of core-shell gold nanorod-PNIPAM nanoparticles.” 2016. Doctoral Dissertation, University of Melbourne. Accessed April 13, 2021. http://hdl.handle.net/11343/113708.

MLA Handbook (7^th Edition):

Jaber, Sarah. “Synthesis and self-assembly of core-shell gold nanorod-PNIPAM nanoparticles.” 2016. Web. 13 Apr 2021.

Vancouver:

Jaber S. Synthesis and self-assembly of core-shell gold nanorod-PNIPAM nanoparticles. [Internet] [Doctoral dissertation]. University of Melbourne; 2016. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/11343/113708.

Council of Science Editors:

Jaber S. Synthesis and self-assembly of core-shell gold nanorod-PNIPAM nanoparticles. [Doctoral Dissertation]. University of Melbourne; 2016. Available from: http://hdl.handle.net/11343/113708

Uniwersytet im. Adama Mickiewicza w Poznaniu

5. Deptuła, Tobiasz. pNiPAM nanoparticles suspensions as crowded complex model systems: synthesis, characterization and properties .

Degree: 2016, Uniwersytet im. Adama Mickiewicza w Poznaniu

URL: http://hdl.handle.net/10593/14367

► Improvements in controlled polymer synthesis and characterization methods have lead scientists to investigate new materials that would not only improve old techniques, but also open… (more)

Subjects/Keywords: nanocząstki; Nnaoparticles; pNiPAM; dyfuzja; difiusion; FCS

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Deptuła, T. (2016). pNiPAM nanoparticles suspensions as crowded complex model systems: synthesis, characterization and properties . (Doctoral Dissertation). Uniwersytet im. Adama Mickiewicza w Poznaniu. Retrieved from http://hdl.handle.net/10593/14367

Chicago Manual of Style (16^th Edition):

Deptuła, Tobiasz. “pNiPAM nanoparticles suspensions as crowded complex model systems: synthesis, characterization and properties .” 2016. Doctoral Dissertation, Uniwersytet im. Adama Mickiewicza w Poznaniu. Accessed April 13, 2021. http://hdl.handle.net/10593/14367.

MLA Handbook (7^th Edition):

Deptuła, Tobiasz. “pNiPAM nanoparticles suspensions as crowded complex model systems: synthesis, characterization and properties .” 2016. Web. 13 Apr 2021.

Vancouver:

Deptuła T. pNiPAM nanoparticles suspensions as crowded complex model systems: synthesis, characterization and properties . [Internet] [Doctoral dissertation]. Uniwersytet im. Adama Mickiewicza w Poznaniu; 2016. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/10593/14367.

Council of Science Editors:

Deptuła T. pNiPAM nanoparticles suspensions as crowded complex model systems: synthesis, characterization and properties . [Doctoral Dissertation]. Uniwersytet im. Adama Mickiewicza w Poznaniu; 2016. Available from: http://hdl.handle.net/10593/14367

Georgia Tech

6. Silva, James Emanuel. PNIPAM hydrogel micro/nanostructures for bulk fluid and droplet control.

Degree: MS, Mechanical Engineering, 2014, Georgia Tech

URL: http://hdl.handle.net/1853/54252

► Poly(N-isopropylacrylamide) (PNIPAM) belongs to a class of stimuli-responsive materials known as “smart” polymers. When cast in the form of a hydrogel, PNIPAM’s lower critical solution… (more)

Subjects/Keywords: Hydrogel; Capillary pressure; Stick and slip; PNIPAM

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Silva, J. E. (2014). PNIPAM hydrogel micro/nanostructures for bulk fluid and droplet control. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/54252

Chicago Manual of Style (16^th Edition):

Silva, James Emanuel. “PNIPAM hydrogel micro/nanostructures for bulk fluid and droplet control.” 2014. Masters Thesis, Georgia Tech. Accessed April 13, 2021. http://hdl.handle.net/1853/54252.

MLA Handbook (7^th Edition):

Silva, James Emanuel. “PNIPAM hydrogel micro/nanostructures for bulk fluid and droplet control.” 2014. Web. 13 Apr 2021.

Vancouver:

Silva JE. PNIPAM hydrogel micro/nanostructures for bulk fluid and droplet control. [Internet] [Masters thesis]. Georgia Tech; 2014. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1853/54252.

Council of Science Editors:

Silva JE. PNIPAM hydrogel micro/nanostructures for bulk fluid and droplet control. [Masters Thesis]. Georgia Tech; 2014. Available from: http://hdl.handle.net/1853/54252

Johannes Gutenberg Universität Mainz

7. Jochum, Florian D. Synthesis and characterization of temperature- and light-responsive polymers and block copolymers.

Degree: 2010, Johannes Gutenberg Universität Mainz

URL: http://ubm.opus.hbz-nrw.de/volltexte/2011/2845/

► In summary, thermoresponsive polyacrylamides with various amounts of different photoswitchable side groups, i. e. azobenzene, salicylideneaniline and fulgimide were successfully prepared. As such, in a… (more)

▼ In summary, thermoresponsive polyacrylamides with various amounts of different photoswitchable side groups, i. e. azobenzene, salicylideneaniline and fulgimide were successfully prepared. As such, in a first step three different chromophores with an amine functionality were synthesized. The synthesis of the stimuli-responsive materials was based on the RAFT polymerization of activated ester acrylates followed by a polymer analogous reaction with different amines. The procedure has been designed to allow the synthesis of well-defined materials with functional groups. All copolymers prepared in this way showed a LCST in aqueous solution. The LCST was in general decreased by increasing the amount of hydrophobic dye incorporated into the thermoresponsive polymer. However, in the case of the fulgimide, the LCST was hardly affected by the chromophore. For azobenzene containing PNIPAM polymers and analogues, higher LCST values were measured after irradiation of the polymer sample solutions with UV-light (Delta LCSTmax = 7.3°C). A reversible light-induced solubility change within a certain temperature range was possible. In contrast to this, irradiated samples of salicylideneaniline containing thermoresponsive copolymers showed an irreversible increase in the LCST (Delta LCSTmax = 13.0°C). Fulgimide chromophores did not influence the LCST of PNIPAM based copolymers after UV-light exposure.rnSimilar to the thermoresponsive polyacrylamides with azobenzene side groups, poly(oligo(ethylene glycol) methyl ether methacrylate) [P(OEGMA)] polymers with azobenzene end groups showed a LCST shift upon UV-irradiation. These polymers were synthesized by RAFT polymerization using a functional chain transfer agent (CTA). For this, PFP-CTA was used as a RAFT-agent for end group functionalization of (thermoresponsive) polymers. In contrast to the statistically arranged copolymers with azobenzene side groups, P(OEGMA) polymers with terminal azobenzene showed a linear increase of the LCST shifts with increasing amount of chromophore (Delta LCSTmax = 4.3°C). Noteworthy, the chemical nature of the end group exhibited a strong influence on the LCST in the case of short thermoresponsive P(OEGMA) polymers.rnThe investigation on temperature- and lightresponsive polymers was transferred onto block copolymers capable to self-assemble into polymeric micelles. Therefore, PEO-b-PNIPAM block copolymers with azobenzene moieties were synthesized successfully. These polymers showed a “smart” behavior in aqueous solution, as the reversible formation and disruption of the micelles could either be controlled by temperature or using light as a stimulus. The usefulness of these materials was demonstrated by encapsulation of a hydrophobic dye in the core of the micelle. Such materials might have a great potential as a model system for several technical or biological applications.rnFinally, double thermoresponsive block copolymers forming micellar structures in a certain temperature range with functional end groups could successfully be synthesized. These “smart…

Subjects/Keywords: PNIPAM; Chromophore; LCST; Reaktivester-Polymere; polymeranaloge Umsetzung; PNIPAM; chromophores; LCST; activated ester polymers; polymer analogous reaction; Chemistry and allied sciences

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Jochum, F. D. (2010). Synthesis and characterization of temperature- and light-responsive polymers and block copolymers. (Doctoral Dissertation). Johannes Gutenberg Universität Mainz. Retrieved from http://ubm.opus.hbz-nrw.de/volltexte/2011/2845/

Chicago Manual of Style (16^th Edition):

Jochum, Florian D. “Synthesis and characterization of temperature- and light-responsive polymers and block copolymers.” 2010. Doctoral Dissertation, Johannes Gutenberg Universität Mainz. Accessed April 13, 2021. http://ubm.opus.hbz-nrw.de/volltexte/2011/2845/.

MLA Handbook (7^th Edition):

Jochum, Florian D. “Synthesis and characterization of temperature- and light-responsive polymers and block copolymers.” 2010. Web. 13 Apr 2021.

Vancouver:

Jochum FD. Synthesis and characterization of temperature- and light-responsive polymers and block copolymers. [Internet] [Doctoral dissertation]. Johannes Gutenberg Universität Mainz; 2010. [cited 2021 Apr 13]. Available from: http://ubm.opus.hbz-nrw.de/volltexte/2011/2845/.

Council of Science Editors:

Jochum FD. Synthesis and characterization of temperature- and light-responsive polymers and block copolymers. [Doctoral Dissertation]. Johannes Gutenberg Universität Mainz; 2010. Available from: http://ubm.opus.hbz-nrw.de/volltexte/2011/2845/

8. Dzhoyashvili, Nina. Integrating the old and new: smart thermoresponsive surfaces and 3D fabrication technologies for tissue engineering .

Degree: 2017, National University of Ireland – Galway

URL: http://hdl.handle.net/10379/6676

► One promising direction of regenerative medicine is the development of cell sheet-based tissue-like constructs. The cell sheets preserve ECM and cell−cell junctions. This may greatly… (more)

Subjects/Keywords: pNIPAm films, cell sheet engineering, 3D printing, tissue decellularization; Chemistry; pNIPAm films; Cell sheet engineering; 3D printing; Tissue decellularization

10 more images…

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APA (6^th Edition):

Dzhoyashvili, N. (2017). Integrating the old and new: smart thermoresponsive surfaces and 3D fabrication technologies for tissue engineering . (Thesis). National University of Ireland – Galway. Retrieved from http://hdl.handle.net/10379/6676

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Dzhoyashvili, Nina. “Integrating the old and new: smart thermoresponsive surfaces and 3D fabrication technologies for tissue engineering .” 2017. Thesis, National University of Ireland – Galway. Accessed April 13, 2021. http://hdl.handle.net/10379/6676.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Dzhoyashvili, Nina. “Integrating the old and new: smart thermoresponsive surfaces and 3D fabrication technologies for tissue engineering .” 2017. Web. 13 Apr 2021.

Vancouver:

Dzhoyashvili N. Integrating the old and new: smart thermoresponsive surfaces and 3D fabrication technologies for tissue engineering . [Internet] [Thesis]. National University of Ireland – Galway; 2017. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/10379/6676.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Dzhoyashvili N. Integrating the old and new: smart thermoresponsive surfaces and 3D fabrication technologies for tissue engineering . [Thesis]. National University of Ireland – Galway; 2017. Available from: http://hdl.handle.net/10379/6676

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

9. Meijer, J.M. Colloidal Crystals of Spheres and Cubes in Real and Reciprocal Space.

Degree: 2015, Universiteit Utrecht

URL: http://dspace.library.uu.nl:8080/handle/1874/311280

► Colloidal suspensions, consisting of nano to micro-meter sized particles dispersed in a liquid, are ubiquitous in daily life. Examples are milk, blood and paint. One… (more)

▼ Colloidal suspensions, consisting of nano to micro-meter sized particles dispersed in a liquid, are ubiquitous in daily life. Examples are milk, blood and paint. One of the most remarkable phenomena exhibited by concentrated suspensions of colloidal particles is the spontaneous self-organization in structures with long-range spatial and/or orientational order, the so-called colloidal crystals. A well-known example of a colloidal crystal is the natural gemstone opal that consists of regular arrays of small spherical silica colloids. The periodic arrays of spheres diffract visible light, giving rise to the opal’s fascinating play of colors. The self-organization of colloidal particles is strongly influenced by their shape. A relatively small change from a sphere to a rounded cube already gives rise to new structures. This thesis is an in-depth study of the effect of colloidal particle shape, namely spheres and cubes, on the self-organization and the final crystal symmetries that can be achieved. The thesis research employs state-of-the-art X-ray diffraction and microscopy techniques for the detailed characterization of colloidal crystal structures prepared using various self-assembly techniques. Furthermore, the thesis shows that by making use of thermo-responsive particle systems, defect formation and diffusion can be studied in situ. The thesis work also reveals the subtle structural variations that arise by changing the particle shape from a sphere to that of a rounded cube. In particular, the roundness of the cube corners combined with the self-organization pathway, convective assembly or sedimentation, is shown to markedly affect final crystal symmetries. In addition, the influence of a magnetic core and the accompanying magnetic attractions between the cubes on the sedimentation behavior and crystal structures of the cubes is investigated, along with their directed assembly in an external magnetic field. Advisors/Committee Members: Lekkerkerker, H.N.W., Philipse, A.P., Petukhov, A.V..

Subjects/Keywords: Colloidal Crystals; Colloids; Cubes; Spheres; PNIPAM; Hematite; Synchrotron X-ray Scattering

11 more images…

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APA (6^th Edition):

Meijer, J. M. (2015). Colloidal Crystals of Spheres and Cubes in Real and Reciprocal Space. (Doctoral Dissertation). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/311280

Chicago Manual of Style (16^th Edition):

Meijer, J M. “Colloidal Crystals of Spheres and Cubes in Real and Reciprocal Space.” 2015. Doctoral Dissertation, Universiteit Utrecht. Accessed April 13, 2021. http://dspace.library.uu.nl:8080/handle/1874/311280.

MLA Handbook (7^th Edition):

Meijer, J M. “Colloidal Crystals of Spheres and Cubes in Real and Reciprocal Space.” 2015. Web. 13 Apr 2021.

Vancouver:

Meijer JM. Colloidal Crystals of Spheres and Cubes in Real and Reciprocal Space. [Internet] [Doctoral dissertation]. Universiteit Utrecht; 2015. [cited 2021 Apr 13]. Available from: http://dspace.library.uu.nl:8080/handle/1874/311280.

Council of Science Editors:

Meijer JM. Colloidal Crystals of Spheres and Cubes in Real and Reciprocal Space. [Doctoral Dissertation]. Universiteit Utrecht; 2015. Available from: http://dspace.library.uu.nl:8080/handle/1874/311280

University of Colorado

10. Kan, Jian. Blebbing of Hydrogel During Volume-Phase Transition.

Degree: MS, 2019, University of Colorado

URL: https://scholar.colorado.edu/mcen_gradetds/197

► Hydrogels are networks of polymer chains that are capable of absorbing solvent to become gel-like elastomeric materials. One common observation is the formation of… (more)

Subjects/Keywords: Blebbing; Hydrogel; Phase-transition; PNIPAm; Shrinking; Soft material; Mechanical Engineering

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APA (6^th Edition):

Kan, J. (2019). Blebbing of Hydrogel During Volume-Phase Transition. (Masters Thesis). University of Colorado. Retrieved from https://scholar.colorado.edu/mcen_gradetds/197

Chicago Manual of Style (16^th Edition):

Kan, Jian. “Blebbing of Hydrogel During Volume-Phase Transition.” 2019. Masters Thesis, University of Colorado. Accessed April 13, 2021. https://scholar.colorado.edu/mcen_gradetds/197.

MLA Handbook (7^th Edition):

Kan, Jian. “Blebbing of Hydrogel During Volume-Phase Transition.” 2019. Web. 13 Apr 2021.

Vancouver:

Kan J. Blebbing of Hydrogel During Volume-Phase Transition. [Internet] [Masters thesis]. University of Colorado; 2019. [cited 2021 Apr 13]. Available from: https://scholar.colorado.edu/mcen_gradetds/197.

Council of Science Editors:

Kan J. Blebbing of Hydrogel During Volume-Phase Transition. [Masters Thesis]. University of Colorado; 2019. Available from: https://scholar.colorado.edu/mcen_gradetds/197

Université Catholique de Louvain

11. Ramirez Wong, Diana Guadalupe. Brushes of self-assembled nanotubes for temperature-responsive biocatalysis.

Degree: 2014, Université Catholique de Louvain

URL: http://hdl.handle.net/2078.1/151206

►

Inspired by the elegant solutions that Nature has provided to control and promote specific site-reactions, my work presents an attempt to mimic filamentous biocatalytic interfaces.… (more)

Subjects/Keywords: PNIPAM; Layer-by-layer; Nanostructures; Enzyme; Membrane-templating

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ramirez Wong, D. G. (2014). Brushes of self-assembled nanotubes for temperature-responsive biocatalysis. (Thesis). Université Catholique de Louvain. Retrieved from http://hdl.handle.net/2078.1/151206

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ramirez Wong, Diana Guadalupe. “Brushes of self-assembled nanotubes for temperature-responsive biocatalysis.” 2014. Thesis, Université Catholique de Louvain. Accessed April 13, 2021. http://hdl.handle.net/2078.1/151206.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ramirez Wong, Diana Guadalupe. “Brushes of self-assembled nanotubes for temperature-responsive biocatalysis.” 2014. Web. 13 Apr 2021.

Vancouver:

Ramirez Wong DG. Brushes of self-assembled nanotubes for temperature-responsive biocatalysis. [Internet] [Thesis]. Université Catholique de Louvain; 2014. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/2078.1/151206.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ramirez Wong DG. Brushes of self-assembled nanotubes for temperature-responsive biocatalysis. [Thesis]. Université Catholique de Louvain; 2014. Available from: http://hdl.handle.net/2078.1/151206

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

KTH

12. Schantz, Cedrik Wiberg von. Ion association to poly(N-isopropylacrylamide) by diffusion and electrophoretic NMR.

Degree: Chemical Science and Engineering (CHE), 2013, KTH

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-158534

► PNIPAM (poly(N-Isopropylacrylamide)) is a well-known thermoresponsive polymer. Dissolved in water, it shows a structural change at 32 ^oC, above which the polymer folds together,… (more)

Subjects/Keywords: PNIPAM; poly(N-isopropylacrylamide); electrophoretic NMR; diffusion NMR; LCST; ion association

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Schantz, C. W. v. (2013). Ion association to poly(N-isopropylacrylamide) by diffusion and electrophoretic NMR. (Thesis). KTH. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-158534

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Schantz, Cedrik Wiberg von. “Ion association to poly(N-isopropylacrylamide) by diffusion and electrophoretic NMR.” 2013. Thesis, KTH. Accessed April 13, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-158534.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Schantz, Cedrik Wiberg von. “Ion association to poly(N-isopropylacrylamide) by diffusion and electrophoretic NMR.” 2013. Web. 13 Apr 2021.

Vancouver:

Schantz CWv. Ion association to poly(N-isopropylacrylamide) by diffusion and electrophoretic NMR. [Internet] [Thesis]. KTH; 2013. [cited 2021 Apr 13]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-158534.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Schantz CWv. Ion association to poly(N-isopropylacrylamide) by diffusion and electrophoretic NMR. [Thesis]. KTH; 2013. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-158534

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

13. D'Eramo, Loïc. Réalisation d'actionneurs à base d'hydrogel thermosensible et étude du glissement par nanovélocimétrie : Implementation of actuators based on thermosensitive hydrogel and study of slippage by nanovelocimetry.

Degree: Docteur es, Microfluidique, physique des liquides, 2016, Université Pierre et Marie Curie – Paris VI

URL: http://www.theses.fr/2016PA066683

►

Cette thèse traite de deux projets en rapport avec la microfluidique. Le premier est consacré à la réalisation d'actionneurs à base d'hydrogel thermosensible. Avec une… (more)

▼

Cette thèse traite de deux projets en rapport avec la microfluidique. Le premier est consacré à la réalisation d'actionneurs à base d'hydrogel thermosensible. Avec une approche technologique basée sur le greffage et la structuration d'un hydrogel thermosensible sur des surfaces en verre, nous montrons comment un matériau capable de subir de fortes variations de volume peut être utilisé comme actionneur microfluidique dans les milieux aqueux. D'abord, en tant que vanne, nous démontrons que la stratégie de greffage des structures permet d'obtenir des actionneurs robustes et durables capables de réguler la circulation de fluides en micro-canaux avec une réponse rapide en miniaturisant la stimulation thermique. Ensuite, une autre configuration, dite de compartimentation libre, est mise en oeuvre et appliquée en biologies moléculaire et cellulaire. Le second est quant à lui dédié à l'étude du glissement par nanovélocimétrie en utilisant la technique de microscopie de fluorescence par réflexion totale interne. Cette technique permet de suivre les écoulement de nanoparticules à proximité immédiate de la paroi d'un micro-canal (dans les premiers 800nm de fluide). En utilisant les modèles de Langevin, nous avons été en mesure de prendre en compte différents artéfacts expérimentaux et les corriger. Nous confirmons l'absence de glissement de l'eau pure sur surface hydrophile et l'existence du glissement sur surface hydrophobe. Cette partie est traitée sous la forme d'une brève introduction, suivie d'un article publié dans Journal of Fluid Mechanics.

In this work, we have addressed two projects related to microfluidics.The first one is dedicated to the integration of hydrogel-based actuators in microsystems. Thanks toa technological approach based on the grafting and patterning of a thermosensitive hydrogel on glasssubstrates, we show how a material that can undergo large volume changes can be embedded as anactuator for aqueous solutions. First as a valve, we prove that the strategy consisting in grafting patternsof hydrogel enables us to obtain robust actuators able to regulate flows in micro-channels, and with afast response by miniaturising the thermal stimulation. Then we report another configuration called freecompartmentalization, applied to molecular and cellular biology. The second part of this manuscript deals with the study of slippage by nanovelocimetry using the totalinternal reflection fluorescence microscopy technique. This method enables us to follow fluorescent nanoparticlesflowing near the wall of a microchannel (within the first 800nm ). Using Langevin simulations,we have been able to take several experimental biases into account and correct them. We can confirmthe no-slip condition of water on hydrophilic surfaces and the actual slippage over hydrophobic surfaces.This part is made of a brief introduction followed by an publication in Journal of Fluid Mechanics.

Advisors/Committee Members: Tabeling, Patrick (thesis director).

Subjects/Keywords: Microfluidique; Hydrogel; Actionneur; Stimulus; PNIPAM; Glissement; Microfluidics; Thermosensitive hydrogel; Actuators; 532.4

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

D'Eramo, L. (2016). Réalisation d'actionneurs à base d'hydrogel thermosensible et étude du glissement par nanovélocimétrie : Implementation of actuators based on thermosensitive hydrogel and study of slippage by nanovelocimetry. (Doctoral Dissertation). Université Pierre et Marie Curie – Paris VI. Retrieved from http://www.theses.fr/2016PA066683

Chicago Manual of Style (16^th Edition):

D'Eramo, Loïc. “Réalisation d'actionneurs à base d'hydrogel thermosensible et étude du glissement par nanovélocimétrie : Implementation of actuators based on thermosensitive hydrogel and study of slippage by nanovelocimetry.” 2016. Doctoral Dissertation, Université Pierre et Marie Curie – Paris VI. Accessed April 13, 2021. http://www.theses.fr/2016PA066683.

MLA Handbook (7^th Edition):

D'Eramo, Loïc. “Réalisation d'actionneurs à base d'hydrogel thermosensible et étude du glissement par nanovélocimétrie : Implementation of actuators based on thermosensitive hydrogel and study of slippage by nanovelocimetry.” 2016. Web. 13 Apr 2021.

Vancouver:

D'Eramo L. Réalisation d'actionneurs à base d'hydrogel thermosensible et étude du glissement par nanovélocimétrie : Implementation of actuators based on thermosensitive hydrogel and study of slippage by nanovelocimetry. [Internet] [Doctoral dissertation]. Université Pierre et Marie Curie – Paris VI; 2016. [cited 2021 Apr 13]. Available from: http://www.theses.fr/2016PA066683.

Council of Science Editors:

D'Eramo L. Réalisation d'actionneurs à base d'hydrogel thermosensible et étude du glissement par nanovélocimétrie : Implementation of actuators based on thermosensitive hydrogel and study of slippage by nanovelocimetry. [Doctoral Dissertation]. Université Pierre et Marie Curie – Paris VI; 2016. Available from: http://www.theses.fr/2016PA066683

14. Saleem, Qasim. Development of Multi‐purpose Lipid Coated PNIPAM Microgels and Techniques for Characterizing Lateral Diffusion in Bilayers.

Degree: 2014, University of Toronto

URL: http://hdl.handle.net/1807/65747

►

The pursuit of a greater understanding of the biological membrane has led to the development of a number of mimetics and probing techniques. This thesis… (more)

▼

The pursuit of a greater understanding of the biological membrane has led to the development of a number of mimetics and probing techniques. This thesis contributes to both of these efforts. Towards the development of mimetics, poly(N-isopropylacrylamide) (pNIPAM) microgels were explored as membrane supports. PNIPAM microgels are “smart” materials that experience a volume phase transition (VPT) at ~32°C, where they undergo a severe loss in volume. The core-shell microgels were synthesized with a low crosslinked pNIPAM core covered by a highly crosslinked pNIPAM shell that was functionalized with exploitable carboxylates. It was shown that a lipid bilayer could be coated on these microgels using either liposomes or bicelles. Specifically, lipid bilayer enclosed microgels made with liposomes (“Lipogels”) were created by using hydrophobically modified microgels, which possessed the ability to sequester liposomes that could ultimately be fused into a continuous bilayer. It was also found that above the VPT temperature, surface decoupled lipid protrude into highly curved structures. Hence, the VPT property could be used to control the curvature of the Lipogel bilayer. These particles could be useful platforms for conducting biophysical membrane studies as well as drug delivery vehicles. Bicelles were also explored as lipid sources for microgel coating, resulting in the creation of “Bicellogels”. Electrostatic attraction between cationic bicelles and unmodified anionic core-shell pNIPAM microgels resulted in the coating of the latter. Astonishingly, the resulting bilayer was made up of only the long chain bicellar lipid. Due to the simplicity of this method, it could be extended to easily coat all types of soft material. The last development on the pNIPAM front involved the coupling of intact liposomes to microgels to create “VESCOgels”. These complexes offer two distinct cargo holds through which temporally distinct release can be achieved. Hence, they could be very useful for applications in tandem release. Lastly, the 31P CODEX NMR technique was adapted to study the lateral diffusion of phospholipids in large liposomes. This technique allows for the measurement of lateral diffusion coefficients of multiple phospholipids simultaneously. This could prove useful for the study of such biologically relevant phenomena as domain formations and drug-lipid interactions.

PhD

Advisors/Committee Members: Macdonald, Peter, Chemistry.

Subjects/Keywords: pNIPAM; lateral diffusion; 0494

…58 2.3.1 Synthesis and Characterization of HM pNIPAM/p(NIPAM‐co‐AA) Microgels… …81 3.2.2 Fabrication of pNIPAM/p(NIPAM‐co‐AA) Core‐shell Microgels… …107 4.2.2 Synthesis of pNIPAM/p(NIPAM‐co‐AA) Core–Shell Microgels… …33 Figure 1‐14: Image showing the use of bicelles to coat the surface of a pNIPAM microgel… …hydroxysuccinimide ODESSA 1D exchange spectroscopy by sideband alternation pNIPAM Poly(N…

10 more images…

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APA (6^th Edition):

Saleem, Q. (2014). Development of Multi‐purpose Lipid Coated PNIPAM Microgels and Techniques for Characterizing Lateral Diffusion in Bilayers. (Doctoral Dissertation). University of Toronto. Retrieved from http://hdl.handle.net/1807/65747

Chicago Manual of Style (16^th Edition):

Saleem, Qasim. “Development of Multi‐purpose Lipid Coated PNIPAM Microgels and Techniques for Characterizing Lateral Diffusion in Bilayers.” 2014. Doctoral Dissertation, University of Toronto. Accessed April 13, 2021. http://hdl.handle.net/1807/65747.

MLA Handbook (7^th Edition):

Saleem, Qasim. “Development of Multi‐purpose Lipid Coated PNIPAM Microgels and Techniques for Characterizing Lateral Diffusion in Bilayers.” 2014. Web. 13 Apr 2021.

Vancouver:

Saleem Q. Development of Multi‐purpose Lipid Coated PNIPAM Microgels and Techniques for Characterizing Lateral Diffusion in Bilayers. [Internet] [Doctoral dissertation]. University of Toronto; 2014. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1807/65747.

Council of Science Editors:

Saleem Q. Development of Multi‐purpose Lipid Coated PNIPAM Microgels and Techniques for Characterizing Lateral Diffusion in Bilayers. [Doctoral Dissertation]. University of Toronto; 2014. Available from: http://hdl.handle.net/1807/65747

University of South Florida

15. Marcus, Gabriel. A Study of Fe₃O₄ Magnetic Nanoparticle RF Heating in Gellan Gum Polymer Under Various Experimental Conditions for Potential Application in Drug Delivery.

Degree: 2014, University of South Florida

URL: https://scholarcommons.usf.edu/etd/5537

► Magnetic nanoparticles (MNPs) have found use in a wide variety of biomedical applications including hyperthermia, imaging and drug delivery. Certain physical properties, such as the… (more)

Subjects/Keywords: Agar; Linear Response Theory; Magnetite; PNIPAM; Neel relaxation; Physics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Marcus, G. (2014). A Study of Fe₃O₄ Magnetic Nanoparticle RF Heating in Gellan Gum Polymer Under Various Experimental Conditions for Potential Application in Drug Delivery. (Thesis). University of South Florida. Retrieved from https://scholarcommons.usf.edu/etd/5537

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Marcus, Gabriel. “A Study of Fe₃O₄ Magnetic Nanoparticle RF Heating in Gellan Gum Polymer Under Various Experimental Conditions for Potential Application in Drug Delivery.” 2014. Thesis, University of South Florida. Accessed April 13, 2021. https://scholarcommons.usf.edu/etd/5537.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Marcus, Gabriel. “A Study of Fe₃O₄ Magnetic Nanoparticle RF Heating in Gellan Gum Polymer Under Various Experimental Conditions for Potential Application in Drug Delivery.” 2014. Web. 13 Apr 2021.

Vancouver:

Marcus G. A Study of Fe₃O₄ Magnetic Nanoparticle RF Heating in Gellan Gum Polymer Under Various Experimental Conditions for Potential Application in Drug Delivery. [Internet] [Thesis]. University of South Florida; 2014. [cited 2021 Apr 13]. Available from: https://scholarcommons.usf.edu/etd/5537.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Marcus G. A Study of Fe₃O₄ Magnetic Nanoparticle RF Heating in Gellan Gum Polymer Under Various Experimental Conditions for Potential Application in Drug Delivery. [Thesis]. University of South Florida; 2014. Available from: https://scholarcommons.usf.edu/etd/5537

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

16. Oliveira, Tiago Espinosa de. Investigação computacional das propriedades estruturais, termodinâmicas e dinâmicas do polímero termossensível poli(N-isopropilacrilamida) em solução aquosa.

Degree: 2016, Brazil

URL: http://hdl.handle.net/10183/150803

►

Polímeros termossensíveis apresentam grandes alterações em suas propriedades quando submetidos a pequenas mudanças de temperatura (T) próximas à temperatura de solução crítica inferior (LCST) ou… (more)

▼

Polímeros termossensíveis apresentam grandes alterações em suas propriedades quando submetidos a pequenas mudanças de temperatura (T) próximas à temperatura de solução crítica inferior (LCST) ou superior (UCST). Um dos polímeros termossensíveis mais estudados é o Poli(N-isopropilacrilamida) (PNIPAm) porque ele apresenta a LCST, aproximadamente, 32 °C ( 305 K), próxima à temperatura do corpo humano. Em temperatura abaixo da LCST o polímero apresenta-se solúvel devido um grande número de interações hidrofílicas (ligações de hidrogênio polímero-água), entretanto quando a temperatura é elevada acima da LCST ocorre a precipitação do polímero devido a um aumento de interações polímero-polímero e uma diminuição brusca nas interações polímero-água. Com essas características o PNIPAm tem despertado o interesse para aplicações em um vasto campo de pesquisas, como por exemplo na liberação controladas de fármacos. Nesse trabalho, utilizando simulações de dinâmica molecular (DM), foi proposta uma imagem microscópica do fenômeno de transição de fases apresentado por esse polímero em solução aquosa influenciado por alterações na estereoquímica do backbone (taticidade), bem como o efeito da copolimerização com Acrilamida (Am). Com base nas análises estruturais e termodinâmicas, os resultados sugerem que as diferentes estereoquímicas (isotático, atático e sindiotático) possibilitam diferentes conformações dificultando ou possibilitado um maior número de interações polímero-polímero e polímero água modificando a LCST. Já o aumento da concentração de Am (xAm) na copolimerização aumenta o número de interações polímero-água dificultando o colapso da cadeia.

Thermosensitive polymers exhibit large changes in their properties when submitted to small changes in temperature T, near the lower (LCST) or upper critical solution temperature( UCST). The most extensively studied thermosensitive polymer is PNIPAm because it has a LCST of approximately 32 °C (305 K), near human body temperature. For temperatures below the LCST the polymer is soluble due to strong hydrophilic interactions (polymer-water hydrogen bonds). However, when the temperature is raised above the LCST, the precipitation of the polymer occurs due to increased polymer-polymer interactions and a sharp decrease in polymer-water interactions. That feature makes the PNIPAm a compound widely studied and with a wide range of applications, such as for drug delivery. In this work, using molecular dynamics simulations, it was proposed a microscopic picture of the phase transition phenomenon presented by this polymer in aqueous solution influenced by changes in stereochemistry of the backbone (tacticity), as well as the effect of copolymerization with acrylamide (Am). Based on the thermodynamic and structural analysis, the results suggest that different stereochemistries (isotactic, atactic and syndiotactic) enable different conformations allowing different scenarios of polymer-polymer and polymer-water interactions, therefore modifying the LCST. The presence of the strongly polar…

Advisors/Committee Members: Netz, Paulo Augusto.

Subjects/Keywords: Dinâmica molecular; Polímeros inteligentes; Copolímeros; PNIPAm; LCST; Thermosensitive polymers

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Oliveira, T. E. d. (2016). Investigação computacional das propriedades estruturais, termodinâmicas e dinâmicas do polímero termossensível poli(N-isopropilacrilamida) em solução aquosa. (Doctoral Dissertation). Brazil. Retrieved from http://hdl.handle.net/10183/150803

Chicago Manual of Style (16^th Edition):

Oliveira, Tiago Espinosa de. “Investigação computacional das propriedades estruturais, termodinâmicas e dinâmicas do polímero termossensível poli(N-isopropilacrilamida) em solução aquosa.” 2016. Doctoral Dissertation, Brazil. Accessed April 13, 2021. http://hdl.handle.net/10183/150803.

MLA Handbook (7^th Edition):

Oliveira, Tiago Espinosa de. “Investigação computacional das propriedades estruturais, termodinâmicas e dinâmicas do polímero termossensível poli(N-isopropilacrilamida) em solução aquosa.” 2016. Web. 13 Apr 2021.

Vancouver:

Oliveira TEd. Investigação computacional das propriedades estruturais, termodinâmicas e dinâmicas do polímero termossensível poli(N-isopropilacrilamida) em solução aquosa. [Internet] [Doctoral dissertation]. Brazil; 2016. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/10183/150803.

Council of Science Editors:

Oliveira TEd. Investigação computacional das propriedades estruturais, termodinâmicas e dinâmicas do polímero termossensível poli(N-isopropilacrilamida) em solução aquosa. [Doctoral Dissertation]. Brazil; 2016. Available from: http://hdl.handle.net/10183/150803

University of Rochester

17. Basu Roy, Dhrubajyoti. Exploiting the Self-assembly of Hydrogel Nanoparticles for Novel Applications in Biosensor Design and Cell Patterning.

Degree: PhD, 2015, University of Rochester

URL: http://hdl.handle.net/1802/29357

► Nanoscale Engineering is fast becoming increasingly vital to tackle several key challenges in biosensor design and tissue engineering. Nanoparticles are a powerful and versatile tool… (more)

Subjects/Keywords: PNIPAM; Photonic Crystal; Topographical Selectivity; Tissue Engineering; Protein Passivation; Blocking; Adhesion; Proliferation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Basu Roy, D. (2015). Exploiting the Self-assembly of Hydrogel Nanoparticles for Novel Applications in Biosensor Design and Cell Patterning. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/29357

Chicago Manual of Style (16^th Edition):

Basu Roy, Dhrubajyoti. “Exploiting the Self-assembly of Hydrogel Nanoparticles for Novel Applications in Biosensor Design and Cell Patterning.” 2015. Doctoral Dissertation, University of Rochester. Accessed April 13, 2021. http://hdl.handle.net/1802/29357.

MLA Handbook (7^th Edition):

Basu Roy, Dhrubajyoti. “Exploiting the Self-assembly of Hydrogel Nanoparticles for Novel Applications in Biosensor Design and Cell Patterning.” 2015. Web. 13 Apr 2021.

Vancouver:

Basu Roy D. Exploiting the Self-assembly of Hydrogel Nanoparticles for Novel Applications in Biosensor Design and Cell Patterning. [Internet] [Doctoral dissertation]. University of Rochester; 2015. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1802/29357.

Council of Science Editors:

Basu Roy D. Exploiting the Self-assembly of Hydrogel Nanoparticles for Novel Applications in Biosensor Design and Cell Patterning. [Doctoral Dissertation]. University of Rochester; 2015. Available from: http://hdl.handle.net/1802/29357

18. Ciocoiu, Oana Nicoleta. Grafting of sodium alginate with poly (N-isopropylacrylamide) chains. Study of the thermothickening behavior.

Degree: 2010, University of Patras

URL: http://nemertes.lis.upatras.gr/jspui/handle/10889/3213

►

Designing new materials with improved or tailored properties is one of the main goals of the chemists. Two common ways are mainly used to get… (more)

▼

Designing new materials with improved or tailored properties is one of the main goals of the chemists. Two common ways are mainly used to get a material with improved or new properties: blending or chemical synthesis. Chemical synthesis is an unlimited method to get new substances with well-defined properties even it is often time consuming and not seldom costly.A rheology study has shown a considerable increase in viscosity of 1% aqueous solutions, 40 and 120 times at 550C, for the graft copolymers with a composition 67 and 80% in PNIPAM respectively as temperature increases above 350C. This behaviour is also related with a critical concentration that has been found around 0.6% for the same copolymers. Fluorescence measurements have shown that this behavior is related with the hydrophobic character and aggregation of PNIPAM chains by increasing temperature over 350C. A dynamic light scattering study in dilute aqueous solutions by varying temperature could provide more information on the kind of the transition taking place and the nature of the particles formed as temperature increases.

Ο σχεδιασμός νέων υλικών με βελτιωμένες ιδιότητες είναι ένας από τους κύριους στόχους των χημικών. Δύο είναι οι πιο συνηθισμένοι τρόποι που χρησιμοποιούνται κυρίως για τη παραλαβή ενός υλικού με βελτιωμένες ή νέες ιδιότητες: ανάμειξη ή χημική σύνθεση. Χημική σύνθεση είναι η μέθοδος όπου λαμβάνονται νέα υλικά με καθορισμένες ιδιότητες αλλά έχει ως μειονέκτημα το κόστος και είναι συχνά χρονοβόρα.Μετρήσεις ρεολογίας έδειξαν μια αξιοσημείωτη αύξηση στο ιξώδες του 1% υδατικού διαλύματος, από 40 μέχρι 120 φορές στους 550C, για συστάσεις του εμβολιασμένου συμπολυμερούς σε PNIPAM 67 εως 80% αντίστοιχα, καθώς η θερμοκρασία αυξάνεται πάνω από τους 350C. Επιπλέον αυτή η συμπεριφορά σχετίζεται με μια κρίσιμη συγκέντρωση που βρέθηκε ίση με 0,6% για τα ίδια συμπολυμερή. Μετρήσεις φθορισμού έδειξαν ότι αυτή η συμπεριφορά σχετίζεται άμεσα με τον υδρόφοβο χαρακτήρα του PNIPAM καθώς η θερμοκρασία αυξάνεται πάνω από τους 350C. Μετρήσεις με δυναμική σκέδαση φωτός σε αραιά υδατικά διαλύματα σε διάφορες θερμοκρασίες μπορούν να δώσουν επιπλέον πληροφορίες για τη μετάπτωση που λαμβάνει χώρα και τη φύση των σωματιδίων όσο η θερμοκρασία αυξάνεται.

Advisors/Committee Members: Στάικος, Γεώργιος, Τσιοκόιου, Οάνα Νικολέτα, Τσιτσιλιάνης, Κωνσταντίνος, Μπόκιας, Γεώργιος, Στάικος, Γεώργιος.

Subjects/Keywords: Sodium alginate; Thermothickening; PNIPAM; 547.782; Αλγινικό οξύ; Μελέτη θερμικής συμπεριφοράς; Πολυ (Ν -ισοπροπυλακρυλαμίδιο)

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APA (6^th Edition):

Ciocoiu, O. N. (2010). Grafting of sodium alginate with poly (N-isopropylacrylamide) chains. Study of the thermothickening behavior. (Masters Thesis). University of Patras. Retrieved from http://nemertes.lis.upatras.gr/jspui/handle/10889/3213

Chicago Manual of Style (16^th Edition):

Ciocoiu, Oana Nicoleta. “Grafting of sodium alginate with poly (N-isopropylacrylamide) chains. Study of the thermothickening behavior.” 2010. Masters Thesis, University of Patras. Accessed April 13, 2021. http://nemertes.lis.upatras.gr/jspui/handle/10889/3213.

MLA Handbook (7^th Edition):

Ciocoiu, Oana Nicoleta. “Grafting of sodium alginate with poly (N-isopropylacrylamide) chains. Study of the thermothickening behavior.” 2010. Web. 13 Apr 2021.

Vancouver:

Ciocoiu ON. Grafting of sodium alginate with poly (N-isopropylacrylamide) chains. Study of the thermothickening behavior. [Internet] [Masters thesis]. University of Patras; 2010. [cited 2021 Apr 13]. Available from: http://nemertes.lis.upatras.gr/jspui/handle/10889/3213.

Council of Science Editors:

Ciocoiu ON. Grafting of sodium alginate with poly (N-isopropylacrylamide) chains. Study of the thermothickening behavior. [Masters Thesis]. University of Patras; 2010. Available from: http://nemertes.lis.upatras.gr/jspui/handle/10889/3213

Harvard University

19. Muluneh, Melaku. Soft Colloids from p(NIPAm-co-AAc): Packing Dynamics and Structure.

Degree: PhD, Physics, 2012, Harvard University

URL: http://nrs.harvard.edu/urn-3:HUL.InstRepos:9366578

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Traditionally, the experimental model of choice for studying the structure and dynamics of glasses or crystals are hard-sphere colloids. An analogy with molecular or atomic… (more)

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Traditionally, the experimental model of choice for studying the structure and dynamics of glasses or crystals are hard-sphere colloids. An analogy with molecular or atomic materials is often drawn, in which each colloidal particle represents an atom or a molecule. Making the individual particles deformable allows an even wider range of phenomena to be observed. In this thesis, I report the three-dimensional confocal microscopic study of the structure and dynamics of aqueous suspensions of fluorescently labeled poly(N-Isopropylacrylamide)-co-(Acrylic Acid), or p(NIPAm-co-AAc), microgel particles of hydrodynamic diameter 1.0 - 1.5 μm. Image analysis techniques and particle tracking algorithms are used to quantify the particle dynamics and the suspension structure. The phase behavior of the suspensions is dependent on a number of factors including pH, temperature, and concentration. By adjusting the pH, the interactions between the microgel particles can be tuned from purely repulsive near neutral pH, to weakly attractive at low pH. At low pH and low concentration, dynamic arrest results mainly from crystallization driven by the attraction between particles; crystal nucleation occurs homogeneously throughout the sample. The dynamics is nucleation limited where fast crystallization follows a delay time. At low pH and high concentration, relaxation of the suspension is constrained and it evolves only slightly to form disordered solid. At neutral pH, the dynamics are a function of the particle number concentration only; a high concentration leads to the formation of a disordered soft glassy solid. Additionally, the three-dimensional image stacks are studied to determine crystal structure by calculating pair correlation functions, g(r), bond order parameters, and structure factors, s(q). The results show that crystal structure is independent of concentration, charge, size, and stiffness of particles remaining FCC under all conditions. At low concentrations and low pH, the structures formed are polycrystalline solids. Moreover, the ability of the particles to compress enables the suspensions to maintain their crystal structure when subjected to external stress. The results help us better understand the relationship between dynamics and structure in soft colloidal suspensions, enhance our ability to use the colloids to model materials, and improve applications of the colloids in industrial products.

Physics

Advisors/Committee Members: Weitz, David A. (advisor).

Subjects/Keywords: pNIPAm; physics; condensed matter physics; colloids; crystallization; packing dynamics; packing structure; soft colloids

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APA (6^th Edition):

Muluneh, M. (2012). Soft Colloids from p(NIPAm-co-AAc): Packing Dynamics and Structure. (Doctoral Dissertation). Harvard University. Retrieved from http://nrs.harvard.edu/urn-3:HUL.InstRepos:9366578

Chicago Manual of Style (16^th Edition):

Muluneh, Melaku. “Soft Colloids from p(NIPAm-co-AAc): Packing Dynamics and Structure.” 2012. Doctoral Dissertation, Harvard University. Accessed April 13, 2021. http://nrs.harvard.edu/urn-3:HUL.InstRepos:9366578.

MLA Handbook (7^th Edition):

Muluneh, Melaku. “Soft Colloids from p(NIPAm-co-AAc): Packing Dynamics and Structure.” 2012. Web. 13 Apr 2021.

Vancouver:

Muluneh M. Soft Colloids from p(NIPAm-co-AAc): Packing Dynamics and Structure. [Internet] [Doctoral dissertation]. Harvard University; 2012. [cited 2021 Apr 13]. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:9366578.

Council of Science Editors:

Muluneh M. Soft Colloids from p(NIPAm-co-AAc): Packing Dynamics and Structure. [Doctoral Dissertation]. Harvard University; 2012. Available from: http://nrs.harvard.edu/urn-3:HUL.InstRepos:9366578

National University of Ireland – Galway

20. Fan, Xingliang. Development of Simplified NIPAm-based Thermoresponsive Films for Cell Preservation, Expansion and Differentiation .

Degree: 2013, National University of Ireland – Galway

URL: http://hdl.handle.net/10379/4261

► Traditional cell recovery methodologies cleave cell-to-cell junctions and thus the recovery of an intact cell sheet for use in tissue engineering is rendered impossible. Additionally,… (more)

▼ Traditional cell recovery methodologies cleave cell-to-cell junctions and thus the recovery of an intact cell sheet for use in tissue engineering is rendered impossible. Additionally, these traditional cell detachment techniques can be damaging to cell surface receptors, which in turn can impair subsequent cell function. Thermoresponsive polymer film mediated cell growth and recovery, has become a popular way to recover undamaged cells, with cell to cell junctions and basally deposited ECM maintained. These cell sheets can be then used for tissue engineering purposes or tissue damage repair. Thermoresponsive polymer has a lower critical solution temperature (LCST) in aqueous solution, which phenomenon has been exploited in temperature controlled cell harvesting. It has been shown that variety of thermoresponsive surfaces are generally conducive to reasonable cell growth. Okano et al. have grafted pNIPAm onto tissue culture plastic using electron beam polymerisation to yield an ultra-thin layer of pNIPAm. Maria E Nash has demonstrated that thermoresponsive films deposited using spin coating method were able to yield cell culture delivery substrates. This issue has been focused on further to simplify the preparation techniques for fabricating thermoresponsive films with a view to cell preservation. To this end, thermoresponsive platforms were deposited using the solvent cast method to yield thin, uniform, reproducible films. Solvent casting is a basic, cheap and effective method for fabricating films in the micrometre range of thickness. It was first reported as a method to deposit a thermoresponsive film for cell culture in 1990. For comparison purposes films were prepared using solvent cast method and the spin coating method. Two types of NIPAm-based thermoresponsive polymers were used in this research; the first employed commercially sourced pNIPAm, the second a NIPAm-co-NtBAm copolymer. The advantages of using a commercially sourced polymer system paired with the operationally simple solvent cast/spin coating technique for cell sheet regeneration are that films prepared in this manner can be produced with minimal training and expense and the use of a commercially sourced product avoids the need for complex polymerisation processes. The NIPAm-co-NtBAm copolymer was selected for similar applications, it showed better cell compatibility and had a LCST lower than room temperature, which makes the biomaterial much easier and flexible for routine applications. The deposited films were characterised using a variety of analytical techniques before biological assessment. Studies have shown that there is a correlation between the thickness of the deposited pNIPAm films and successful cell adhesion and proliferation; therefore it was imperative that this parameter could be assessed. Successful cell adhesion onto a biomaterial surface is dependent on a number of physiochemical characteristics such as surface wettability, roughness and composition, therefore where a discernible difference in cell growth was observed between… Advisors/Committee Members: Rochev, Yury (advisor).

Subjects/Keywords: pNIPAm; NIPAm-co-NtBAm; Cell expansion and regeneration; Stem cell differentiation; Thermoresponsive polymers; Biomedical Engineering

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APA (6^th Edition):

Fan, X. (2013). Development of Simplified NIPAm-based Thermoresponsive Films for Cell Preservation, Expansion and Differentiation . (Thesis). National University of Ireland – Galway. Retrieved from http://hdl.handle.net/10379/4261

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Fan, Xingliang. “Development of Simplified NIPAm-based Thermoresponsive Films for Cell Preservation, Expansion and Differentiation .” 2013. Thesis, National University of Ireland – Galway. Accessed April 13, 2021. http://hdl.handle.net/10379/4261.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Fan, Xingliang. “Development of Simplified NIPAm-based Thermoresponsive Films for Cell Preservation, Expansion and Differentiation .” 2013. Web. 13 Apr 2021.

Vancouver:

Fan X. Development of Simplified NIPAm-based Thermoresponsive Films for Cell Preservation, Expansion and Differentiation . [Internet] [Thesis]. National University of Ireland – Galway; 2013. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/10379/4261.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Fan X. Development of Simplified NIPAm-based Thermoresponsive Films for Cell Preservation, Expansion and Differentiation . [Thesis]. National University of Ireland – Galway; 2013. Available from: http://hdl.handle.net/10379/4261

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Newcastle

21. Humphreys, Ben Adam. Nanostructure of temperature responsive polymer brushes modulated by salt identity.

Degree: PhD, 2019, University of Newcastle

URL: http://hdl.handle.net/1959.13/1407888

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Research Doctorate - Doctor of Philosophy (PhD)

Interfacial properties of a surface can be extensively modified through the addition of a polymer brush layer; a… (more)

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Research Doctorate - Doctor of Philosophy (PhD)

Interfacial properties of a surface can be extensively modified through the addition of a polymer brush layer; a dense array of end-tethered polymers grafted to a surface. When a polymer brush is prepared utilising stimulus responsive polymers, the surface properties can be tailored to respond, often reversibly, to external stimuli such as temperature, light, pH, solvent or electric fields. While stimulus responsive polymer brushes, as a whole, are attractive for a wide range of biological and industrial applications, brushes that are temperature responsive have gained considerable interest due to their ability to trigger a brush response without the need of any further additives to the system. However, the thermoresponse of these polymer brushes, like many other physicochemical phenomena can be influenced by the concentration as well as the identity of the salt present. Unlike for untethered polymers, research into specific ions effects for thermoresponsive brushes has be sparse. This knowledge is crucial when considering new applications. Throughout this thesis, advances in the understanding of specific ion effects on the entropically driven thermoresponse of polymer brushes tethered to planar substrates and colloidal silica particles are highlighted. The neutral, thermoresponsive polymer brushes were synthesised via the surface initiated-activators regenerated by electron transfer (SI-ARGET) variant of traditional atom transfer radical polymerisation (ATRP). This synthetic method was optimised for each system and performed in alcohol/water mixtures. Furthermore, this method required significantly reduced concentrations of catalyst compared to traditional ATRP, whilst still having excellent control over the uniformity and thickness of the resulting polymer brush. In situ ellipsometry, atomic force microscopy and neutron reflectometry (NR) were used to thoroughly investigate the specific ion effects on the surface properties and internal structure of two thermoresponsive polymer brushes, poly(N-isopropylacrylamide) (PNIPAM) and poly(di(ethylene glycol) methyl ether methacrylate (PMEO2MA), tethered to planar silicon substrates. It was revealed that strongly hydrated anions reduce the temperature of the conformational swollen-collapsed transition while weakly hydrated anions, such as thiocyanate, not only increase the temperature of the transition, but also influence its overall shape. The temperature response and stability of hybrid PNIPAM brush modified colloidal silica particle dispersions was then investigated using dynamic light scattering and small angle neutron scattering (SANS). Experiments were performed as a function of molecular weight and in the presence of an extended range of salts and concentrations. This research revealed a molecular weight dependent transition temperature which was shifted to higher or lower temperatures depending on the salt identity and concentration. More importantly, unlike planar polymer brushes, the presence of a master curve…

Advisors/Committee Members: University of Newcastle. Faculty of Science, School of Environmental and Life Sciences.

Subjects/Keywords: polymer brush; PNIPAM; Hofmeister; thermoresponsive; PMEO2MA; specific ion effects; thesis by publication

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APA (6^th Edition):

Humphreys, B. A. (2019). Nanostructure of temperature responsive polymer brushes modulated by salt identity. (Doctoral Dissertation). University of Newcastle. Retrieved from http://hdl.handle.net/1959.13/1407888

Chicago Manual of Style (16^th Edition):

Humphreys, Ben Adam. “Nanostructure of temperature responsive polymer brushes modulated by salt identity.” 2019. Doctoral Dissertation, University of Newcastle. Accessed April 13, 2021. http://hdl.handle.net/1959.13/1407888.

MLA Handbook (7^th Edition):

Humphreys, Ben Adam. “Nanostructure of temperature responsive polymer brushes modulated by salt identity.” 2019. Web. 13 Apr 2021.

Vancouver:

Humphreys BA. Nanostructure of temperature responsive polymer brushes modulated by salt identity. [Internet] [Doctoral dissertation]. University of Newcastle; 2019. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1959.13/1407888.

Council of Science Editors:

Humphreys BA. Nanostructure of temperature responsive polymer brushes modulated by salt identity. [Doctoral Dissertation]. University of Newcastle; 2019. Available from: http://hdl.handle.net/1959.13/1407888

Loughborough University

22. Hanga, Mariana P. Controlled particle production by membrane emulsification for mammalian cell culture and release.

Degree: PhD, 2014, Loughborough University

URL: http://hdl.handle.net/2134/14922

► Existing commercially available microcarriers are very efficient at encouraging cell attachment and proliferation. However, recovery of the cells is problematic as it requires the use… (more)

▼ Existing commercially available microcarriers are very efficient at encouraging cell attachment and proliferation. However, recovery of the cells is problematic as it requires the use of proteolytic enzymes which are damaging to critical cell adhesion proteins. From this perspective, temperature responsive polymers appear to be a valid option. The current innovative study is to produce and engineer microcarriers in terms of particle size, surface coating and properties, as well as thermo-responsiveness for cell release. All these benefits are based on particle production by membrane emulsification to provide a highly controlled particle size. The polymer of choice is poly N-isopropylacrylamide (pNIPAM) because of the sharpness of its phase transition, biocompatibility and transition temperature close to the physiological value. These characteristics make pNIPAM a very attractive material for Tissue Engineering applications. Cells are cultured on the hydrophobic surface at 37??C and can be readily detached without using proteolytic enzymes from the surface by lowering the temperature to room temperature. The Dispersion Cell (MicroPore Technologies Ltd, UK) was successfully employed for the production of W/O emulsions. The generated monomer droplets were additionally solidified by applying a free radical polymerisation to manufacture solid pNIPAM microspheres. Additionally, calcium alginate particles were also generated and further functionalised with amine terminated pNIPAM to form temperature responsive core-shell particles by simply taking advantage of the electrostatic interactions between the carboxyl groups of the alginate and amino groups of the modified pNIPAM. Controlled particle production was achieved by varying process parameters and changing the recipe formulation (e.g. monomer concentration, surfactant concentration, pore size and inter-pore spacing, injection rate, shear stress applied at the membrane s surface). The manufactured particles were then analysed in terms of particle size and size distribution, chemical composition, surface analysis, shrinkage ratio and thermo-responsiveness and further sterilised and used for cell culture and release experiments. Swiss Albino 3T3 fibroblastic cells (ATCC, USA) were utilised to show proof-of-concept for this technology. Cell attachment and proliferation were assessed and successfully demonstrated qualitatively and quantitatively. pNIPAM solid particles, uncoated and with different protein coatings were shown to allow a limited degree of cell attachment and proliferation compared to a commercially available microcarrier. On a different approach, uncoated core-shell structures demonstrated improved capabilities for cell attachment and proliferation, similar to commercially available microcarriers. Having in mind the potential of temperature responsive polymers and the aim of this innovative study, cell detachment from the generated microcarriers was evaluated and compared to a commercially available temperature responsive surface. Necessary time for detachment…

Subjects/Keywords: 660.6; Membrane emulsification; pNIPAM; Alginate; Monodisperse; Microcarriers; Non-enzymatic cell harvesting; Core-shell particles

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APA (6^th Edition):

Hanga, M. P. (2014). Controlled particle production by membrane emulsification for mammalian cell culture and release. (Doctoral Dissertation). Loughborough University. Retrieved from http://hdl.handle.net/2134/14922

Chicago Manual of Style (16^th Edition):

Hanga, Mariana P. “Controlled particle production by membrane emulsification for mammalian cell culture and release.” 2014. Doctoral Dissertation, Loughborough University. Accessed April 13, 2021. http://hdl.handle.net/2134/14922.

MLA Handbook (7^th Edition):

Hanga, Mariana P. “Controlled particle production by membrane emulsification for mammalian cell culture and release.” 2014. Web. 13 Apr 2021.

Vancouver:

Hanga MP. Controlled particle production by membrane emulsification for mammalian cell culture and release. [Internet] [Doctoral dissertation]. Loughborough University; 2014. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/2134/14922.

Council of Science Editors:

Hanga MP. Controlled particle production by membrane emulsification for mammalian cell culture and release. [Doctoral Dissertation]. Loughborough University; 2014. Available from: http://hdl.handle.net/2134/14922

23. MacKinnon, Neil J. Investigation of Unilamellar Phospholipid Vesicle Interactions with PNIPAM Based Hydrogel Beads.

Degree: 2009, University of Toronto

URL: http://hdl.handle.net/1807/19288

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Phospholipid liposome binding to hydrogel beads based on poly(N-isopropylacrylamide) (PNIPAM) is accomplished employing either avidin/biotin conjugation or hydrophobic modification of the microgels, and the ability… (more)

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Phospholipid liposome binding to hydrogel beads based on poly(N-isopropylacrylamide) (PNIPAM) is accomplished employing either avidin/biotin conjugation or hydrophobic modification of the microgels, and the ability to form single supported lipid bilayers is explored. The co-monomer acrylic acid (AA), evenly distributed or localized to the shell of the microgel, is included to facilitate post-polymerization chemical modification of the hydrogel beads. The degree of chemical modification of the microgels as well as the thermal behavior is monitored via 1H and 13C nuclear magnetic resonance (NMR). Liposomes composed of 1-palmitoyl-2-oleoyl-sn-glycero-3-phoshocholine (POPC) and a small amount of commercially available biotinylated-lipid are shown to bind as intact entities while sequestering internal contents to biotinylated hydrogel beads, utilizing avidin as the coupling agent. Under fusogenic conditions, these bound liposomes remain as individual vesicles. Alternatively, POPC liposomes are shown to bind to microgels modified to display single chain alkyl groups or cholesteryl moieties, and remain as intact vesicles. It is demonstrated that these liposomes become permeable at high hydrophobe content. Bound liposomes will fuse into larger structures under high hydrophobe content conditions, but remain permeable. The volume phase transition (VPT) characteristic of PNIPAM microgels is shown to influence the permeability of hydrophobically bound (low hydrophobe content), but not avidin/biotin conjugated, liposomes. The degree of liposome binding, as well as their resulting structures and permeability are investigated utilizing 31P NMR, fluorescence spectroscopy and microscopy. The microgel-bound liposome and microgel-supported lipid bilayer hybrid systems would be ideally suited to drug delivery and tissue engineering applications. The microgel-supported single lipid bilayer system would, in addition, potentially act as a cell model system for membrane dynamics and embedded amphiphile NMR studies.

PhD

Advisors/Committee Members: Macdonald, Peter Moore, Chemistry.

Subjects/Keywords: Vesicle; PNIPAM; Microgel; NMR; 0494

…glycol) PNIPAM poly(N-isopropylacrylamide) POPC 1-palmitoyl-2-oleoyl-sn… …details of pNIPAM binding and its influence on liposome properties6-10. Converse to triggering… …properties of this polymer, whereby the solubility of pNIPAM was decreased on raising the… …explanation, proposed by Zeng et al., defines an enthalpy and entropy on solubilizing pNIPAM as… …phase separation occurs. Through studying linear chains of pNIPAM, the thermodynamics of the…

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APA (6^th Edition):

MacKinnon, N. J. (2009). Investigation of Unilamellar Phospholipid Vesicle Interactions with PNIPAM Based Hydrogel Beads. (Doctoral Dissertation). University of Toronto. Retrieved from http://hdl.handle.net/1807/19288

Chicago Manual of Style (16^th Edition):

MacKinnon, Neil J. “Investigation of Unilamellar Phospholipid Vesicle Interactions with PNIPAM Based Hydrogel Beads.” 2009. Doctoral Dissertation, University of Toronto. Accessed April 13, 2021. http://hdl.handle.net/1807/19288.

MLA Handbook (7^th Edition):

MacKinnon, Neil J. “Investigation of Unilamellar Phospholipid Vesicle Interactions with PNIPAM Based Hydrogel Beads.” 2009. Web. 13 Apr 2021.

Vancouver:

MacKinnon NJ. Investigation of Unilamellar Phospholipid Vesicle Interactions with PNIPAM Based Hydrogel Beads. [Internet] [Doctoral dissertation]. University of Toronto; 2009. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1807/19288.

Council of Science Editors:

MacKinnon NJ. Investigation of Unilamellar Phospholipid Vesicle Interactions with PNIPAM Based Hydrogel Beads. [Doctoral Dissertation]. University of Toronto; 2009. Available from: http://hdl.handle.net/1807/19288

Cal Poly

24. Liu, Cheyenne H. Development and Characterization of Reagent Pencils for Microfluidic Paper Based Analytical Devices.

Degree: MS, Chemistry & Biochemistry, 2016, Cal Poly

URL: https://digitalcommons.calpoly.edu/theses/1639 ; 10.15368/theses.2016.103

► Microfluidic paper based analytical devices (microPADs) are a novel platform for point of care (POC) diagnostics. Limitations of reagent shelf life have been overcome… (more)

Subjects/Keywords: reagent pencil microPAD microfluidic PNIPAM click; Analytical Chemistry; Materials Chemistry; Polymer Chemistry

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APA (6^th Edition):

Liu, C. H. (2016). Development and Characterization of Reagent Pencils for Microfluidic Paper Based Analytical Devices. (Masters Thesis). Cal Poly. Retrieved from https://digitalcommons.calpoly.edu/theses/1639 ; 10.15368/theses.2016.103

Chicago Manual of Style (16^th Edition):

Liu, Cheyenne H. “Development and Characterization of Reagent Pencils for Microfluidic Paper Based Analytical Devices.” 2016. Masters Thesis, Cal Poly. Accessed April 13, 2021. https://digitalcommons.calpoly.edu/theses/1639 ; 10.15368/theses.2016.103.

MLA Handbook (7^th Edition):

Liu, Cheyenne H. “Development and Characterization of Reagent Pencils for Microfluidic Paper Based Analytical Devices.” 2016. Web. 13 Apr 2021.

Vancouver:

Liu CH. Development and Characterization of Reagent Pencils for Microfluidic Paper Based Analytical Devices. [Internet] [Masters thesis]. Cal Poly; 2016. [cited 2021 Apr 13]. Available from: https://digitalcommons.calpoly.edu/theses/1639 ; 10.15368/theses.2016.103.

Council of Science Editors:

Liu CH. Development and Characterization of Reagent Pencils for Microfluidic Paper Based Analytical Devices. [Masters Thesis]. Cal Poly; 2016. Available from: https://digitalcommons.calpoly.edu/theses/1639 ; 10.15368/theses.2016.103

25. Skiles, Stephanie Lyn. Chemical and Physical Properties of Nanomaterials for Model Catalytic Systems and Smart Polymer Membranes.

Degree: PhD, Chemistry, 2014, Texas A&M University

URL: http://hdl.handle.net/1969.1/153966

► The increased development of surface science in the last half century has opened up new fields for exploration. Surfaces from the pristine to the complex… (more)

▼ The increased development of surface science in the last half century has opened up new fields for exploration. Surfaces from the pristine to the complex can now be studied with relative ease. These developments along with the industrial society’s desire for improvement have led to the study of smart materials and model systems. Smart materials are designed to have a significant property change in response to a stimulus. Smart polymers can be synthesized that respond to a variety of stimuli including temperature, pH or light. The polymer responds to the stimulus by undergoing a transition that can affect its color, conductivity, shape, etc. Even slight changes in environment can induce large changes in the polymer. This work focuses on covalent layer-by-layer assembly grafts of the thermoresponsive polymer poly(N-isopropylacrylamide) and silica nanoparticles. When grafted to a surface, the system response to external stimuli inducing changes in topography and wettability. Utilizing nanoindentation the polymer graft’s switching elastic modulus was probed as it was exposed to varying external stimuli. It was found that the modulus of the polymer graft changed an order of magnitude based on the polymer’s history and current environment. Covalent layer-by-layer assembly additionally was used to functionalize porous substrates. The polymer’s conformational change was leveraged in the development of an oil and water separation membrane capable of demulsification. The polymer’s transition to a non-soluble configuration blocked pore passageways, preventing the oil from permeating the substrate leading to a pure water filtrate. Advances in surface science have pushed ahead the development of cheaper and better performing catalyst systems. These systems can be developed and tested using model catalyst systems. Herein, two model systems were investigated: a supported cobalt nanoparticle catalyst and a bimetallic palladium-copper system. In the cobalt system, the smallest particles are oxidized and deactivated during the Fischer-Tropsch reaction. In the bimetallic system, the electronic effect of metal alloying was investigated using X-ray photoelectron spectroscopy. The stable alloy was surface enriched with copper. The promotion effect of copper on palladium for the acetylene hydrogenation reaction was investigated. These model systems allow for the study of fundamental phenomena on a controlled surface. Advisors/Committee Members: Batteas, James D (advisor), Bergbreiter, David E (committee member), Hilty, Christian (committee member), Grunlan, Jaime (committee member).

Subjects/Keywords: Smart Polymer; PNIPAM; Model Catalyst

…28 Covalent Layer-by-Layer Assembly of Silicon/(PNIPAM/SiO2)6/PNAIPAM… …32 Covalent Layer-by-Layer Assembly of Silica Frit/(PNIPAM/SiO2)6/PNAIPAM PNIPAM… …PNIPAM. ............................. 7 Figure 2.2. LCST determination of PNIPAM by… …temperature used to determine the LCST of a PNIPAM solution… …10 Figure 2.4. Interaction of Hofmeister anion with PNIPAM…

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APA (6^th Edition):

Skiles, S. L. (2014). Chemical and Physical Properties of Nanomaterials for Model Catalytic Systems and Smart Polymer Membranes. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/153966

Chicago Manual of Style (16^th Edition):

Skiles, Stephanie Lyn. “Chemical and Physical Properties of Nanomaterials for Model Catalytic Systems and Smart Polymer Membranes.” 2014. Doctoral Dissertation, Texas A&M University. Accessed April 13, 2021. http://hdl.handle.net/1969.1/153966.

MLA Handbook (7^th Edition):

Skiles, Stephanie Lyn. “Chemical and Physical Properties of Nanomaterials for Model Catalytic Systems and Smart Polymer Membranes.” 2014. Web. 13 Apr 2021.

Vancouver:

Skiles SL. Chemical and Physical Properties of Nanomaterials for Model Catalytic Systems and Smart Polymer Membranes. [Internet] [Doctoral dissertation]. Texas A&M University; 2014. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1969.1/153966.

Council of Science Editors:

Skiles SL. Chemical and Physical Properties of Nanomaterials for Model Catalytic Systems and Smart Polymer Membranes. [Doctoral Dissertation]. Texas A&M University; 2014. Available from: http://hdl.handle.net/1969.1/153966

University of North Texas

26. Tang, Shijun. Characterization, Properties and Applications of Novel Nanostructured Hydrogels.

Degree: 2006, University of North Texas

URL: https://digital.library.unt.edu/ark:/67531/metadc5605/

► The characterization, properties and applications of the novel nanostructured microgel (nanoparticle network and microgel crystal) composed of poly-N-isopropylacrylanmide-co-allylamine (PNIPAM-co-allylamine) and PNIPAM-co-acrylic acid(AA) have been investigated.… (more)

Subjects/Keywords: hydrogel; PNIPAM; melting; Nanostructured materials.; Colloids.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Tang, S. (2006). Characterization, Properties and Applications of Novel Nanostructured Hydrogels. (Thesis). University of North Texas. Retrieved from https://digital.library.unt.edu/ark:/67531/metadc5605/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Tang, Shijun. “Characterization, Properties and Applications of Novel Nanostructured Hydrogels.” 2006. Thesis, University of North Texas. Accessed April 13, 2021. https://digital.library.unt.edu/ark:/67531/metadc5605/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Tang, Shijun. “Characterization, Properties and Applications of Novel Nanostructured Hydrogels.” 2006. Web. 13 Apr 2021.

Vancouver:

Tang S. Characterization, Properties and Applications of Novel Nanostructured Hydrogels. [Internet] [Thesis]. University of North Texas; 2006. [cited 2021 Apr 13]. Available from: https://digital.library.unt.edu/ark:/67531/metadc5605/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Tang S. Characterization, Properties and Applications of Novel Nanostructured Hydrogels. [Thesis]. University of North Texas; 2006. Available from: https://digital.library.unt.edu/ark:/67531/metadc5605/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

27. Paixão, Marcus Vinicius Gomes. Avaliação do potencial de microesferas magnéticas/termoresponsivas à base de quitosana decoradas com poli (N-Isopropilacrilamida) no tratamento de águas oleosas.

Degree: 2019, Federal University of Rio Grande do Norte

URL: https://repositorio.ufrn.br/jspui/handle/123456789/27571

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Microesferas inteligentes capazes de responder a campos magnéticos e mudanças de temperatura foram preparadas encapsulando nanopartículas… (more)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Microesferas inteligentes capazes de responder a campos magnéticos e mudanças de temperatura foram preparadas encapsulando nanopartículas magnéticas em microesferas de quitosana reticuladas, seguidas pela formação de escovas de poli(N-isopropilacrilamida) (PNIPAM) em suas superfícies (MMQ-PNIPAM). As microesferas sintetizadas foram caracterizadas por espectroscopia de absorção na região do infravermelho por transformada de Fourier (FTIR), microscopia eletrônica de transmissão (TEM), magnetometria de amostra vibrante (VSM), termogravimetria (TG) e calorimetria exploratória diferencial (DSC). Enquanto a maioria dos estudos objetivou a reação de copolimerização por enxertia entre quitosana e NIPAM para obter uma partícula solúvel, a principal contribuição deste estudo foi melhorar a lipofilicidade de microesferas magnéticas de quitosana reticulada com escovas de PNIPAM, para ser usada no tratamento de água oleosa como adsorvente sólido. Além disso, aplicou-se a MMQ-PNIPAM de forma associada ao homopolímero PNIPAM em um processo de remoção de óleo. Comumente, a composição da água oleosa de um poço de petróleo é caracterizada por alta salinidade e alto teor de óleo. Logo, investigou-se neste trabalho o comportamento termoresponsivo da PNIPAM na presença de sais (NaCl e CaCl2), bem como a eficiência de remoção de óleo devido ao efeito de agrupamento de partículas MMQPNIPAM acima da temperatura de agregação da PNIPAM. O comportamento termoresponsivo das MMQ-PNIPAM foi confirmado pela transição de fase acentuada nas curvas de DSC. A investigação inicial da eficiência de remoção de óleo foi realizada com as microesferas sintetizadas atingindo valores superiores a 97% acima da temperatura de agregação. Por outro lado, os resultados mostraram que o tempo é um parâmetro importante para obter maior remoção de óleo, principalmente devido ao efeito de salinidade, e a presença de cadeias de homopolímeros PNIPAM pode conferir vantagens significativas em comparação ao desempenho de microesferas MMQ-PNIPAM individuais.

Smart microspheres capable of responding to magnetic fields and temperature changes were prepared by encapsulating magnetic nanoparticles into cross-linked chitosan microspheres followed by poly(N-isopropylacrylamide) (PNIPAM) brushes formation on their surfaces (MCM-PNIPAM). The synthetized microspheres were characterized by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), thermogravimetry (TG) and differential scanning calorimetry (DSC). While most studies have focused on the graft copolymerization reaction between chitosan and NIPAM to get a soluble particle, the main finding of this study was to improve the lipophilicity of magnetic crosslinked chitosan microspheres with PNIPAM brushes, in order to be used in oily water treatment as a solid adsorbent. In addition, we applied MCMPNIPAM associated to PNIPAM homopolymer in oil removal…

Advisors/Committee Members: Fonseca, José Luis Cardozo, Nunes, Juliana de Souza, Galvão, Luzia Patricia Fernandes de Carvalho, Villetti, Marcos Antonio, Balaban, Rosângela de Carvalho.

Subjects/Keywords: CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA; Microesferas; Quitosana; PNIPAM; Termoresponsivo; Águas oleosas

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Paixão, M. V. G. (2019). Avaliação do potencial de microesferas magnéticas/termoresponsivas à base de quitosana decoradas com poli (N-Isopropilacrilamida) no tratamento de águas oleosas. (Doctoral Dissertation). Federal University of Rio Grande do Norte. Retrieved from https://repositorio.ufrn.br/jspui/handle/123456789/27571

Chicago Manual of Style (16^th Edition):

Paixão, Marcus Vinicius Gomes. “Avaliação do potencial de microesferas magnéticas/termoresponsivas à base de quitosana decoradas com poli (N-Isopropilacrilamida) no tratamento de águas oleosas.” 2019. Doctoral Dissertation, Federal University of Rio Grande do Norte. Accessed April 13, 2021. https://repositorio.ufrn.br/jspui/handle/123456789/27571.

MLA Handbook (7^th Edition):

Paixão, Marcus Vinicius Gomes. “Avaliação do potencial de microesferas magnéticas/termoresponsivas à base de quitosana decoradas com poli (N-Isopropilacrilamida) no tratamento de águas oleosas.” 2019. Web. 13 Apr 2021.

Vancouver:

Paixão MVG. Avaliação do potencial de microesferas magnéticas/termoresponsivas à base de quitosana decoradas com poli (N-Isopropilacrilamida) no tratamento de águas oleosas. [Internet] [Doctoral dissertation]. Federal University of Rio Grande do Norte; 2019. [cited 2021 Apr 13]. Available from: https://repositorio.ufrn.br/jspui/handle/123456789/27571.

Council of Science Editors:

Paixão MVG. Avaliação do potencial de microesferas magnéticas/termoresponsivas à base de quitosana decoradas com poli (N-Isopropilacrilamida) no tratamento de águas oleosas. [Doctoral Dissertation]. Federal University of Rio Grande do Norte; 2019. Available from: https://repositorio.ufrn.br/jspui/handle/123456789/27571

University of Rochester

28. Lifson, Mark. Nanoparticles as tools for nano-/micro- biosystems.

Degree: PhD, 2015, University of Rochester

URL: http://hdl.handle.net/1802/29252

► Nanoscale interactions are at the heart of almost all biochemical processes, and understanding them using biosensors is an important and challenging problem in biology and… (more)

Subjects/Keywords: Photonic crystal; Arrayed imaging reflectometry; Hydrogel nanoparticles; PNIPAM; Biosensing; Virus-like particles; VLP; Human papilloma virus; HPV; Label-free

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lifson, M. (2015). Nanoparticles as tools for nano-/micro- biosystems. (Doctoral Dissertation). University of Rochester. Retrieved from http://hdl.handle.net/1802/29252

Chicago Manual of Style (16^th Edition):

Lifson, Mark. “Nanoparticles as tools for nano-/micro- biosystems.” 2015. Doctoral Dissertation, University of Rochester. Accessed April 13, 2021. http://hdl.handle.net/1802/29252.

MLA Handbook (7^th Edition):

Lifson, Mark. “Nanoparticles as tools for nano-/micro- biosystems.” 2015. Web. 13 Apr 2021.

Vancouver:

Lifson M. Nanoparticles as tools for nano-/micro- biosystems. [Internet] [Doctoral dissertation]. University of Rochester; 2015. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1802/29252.

Council of Science Editors:

Lifson M. Nanoparticles as tools for nano-/micro- biosystems. [Doctoral Dissertation]. University of Rochester; 2015. Available from: http://hdl.handle.net/1802/29252

North Carolina State University

29. Jeong, Chang Woo. Interfacial Phenomena on Polymetric Thin Films.

Degree: MS, Wood and Paper Science, 2006, North Carolina State University

URL: http://www.lib.ncsu.edu/resolver/1840.16/204

► Model thin films relevant to various biomaterials applications were used to investigate the interfacial phenomena that occur on polymeric surfaces. Quartz Crystal Microbalance with Dissipation… (more)

▼ Model thin films relevant to various biomaterials applications were used to investigate the interfacial phenomena that occur on polymeric surfaces. Quartz Crystal Microbalance with Dissipation (QCM-D) was used to investigate conformational change of soft materials, adsorption and desorption kinetics of macromolecules and interaction between absorbates and model surfaces. Specifically, this thesis deals with enzymatic activity on this films of cellulose of lignin, and salt- induced changes for surface-grafted neutral thermoresponsive polymers. It was possible to study in situ and in real time the dynamics of enzymatic activity with the QCM-D. After an initial phase, which was controlled by enzyme binding on the substrate, an increase in the resonant frequency of the sensor was apparent. This increase of frequency was explained by the reduction in effective mass due to enzymatic degradation. The rate at which this degradation occurs was found to depend strongly on the enzyme concentration, temperature and the pH of the solution as well as the mixing conditions within the reaction cell. QCM-D was also employed to estimate the effect of salt on the volume phase transition of thermoresponsive polymer brushes. Changes in mass and viscoelasticity of grafted poly (N-isopropyl acrylamide) (PNIPAM) layers grafted from QCM-D sensors were measured as a function of temperature, upon contact with aqueous solutions of variable salt concentration. The phase transition temperature of PNIPAM brushes, TC,graft, quantified by using the QCM-D was reduced with increases in the concentration of salt. This phenomenon is explained by the tendency of salt ions to affect structure of water molecules (Hofmeister effect). The investigation on changes in the hydrophlicity of milled wood lignin films were studied by QCM-D and static contact angle mesurements. After laccase incubation, significant decrease in resonant frequency and increase in energy dissipation was observed. It was demonstrated that the film became less hydrophobic due to the oxidation by laccase. Overall, this thesis demonstrates the potential of QCM-D to characterize the detailed kinetics of enzyme activity and to monitor the conformational changes of polymer brushes grafted on the surface of QCM resonator. Advisors/Committee Members: Dr. Dimitris S. Argyropoulos, Committee Co-Chair (advisor), Dr. Martin A. Hubbe, Committee Member (advisor), Dr. Orlando J. Rojas, Committee Chair (advisor).

Subjects/Keywords: QCM-D; lignin; cellulose; PNIPAM; thin films

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Jeong, C. W. (2006). Interfacial Phenomena on Polymetric Thin Films. (Thesis). North Carolina State University. Retrieved from http://www.lib.ncsu.edu/resolver/1840.16/204

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Jeong, Chang Woo. “Interfacial Phenomena on Polymetric Thin Films.” 2006. Thesis, North Carolina State University. Accessed April 13, 2021. http://www.lib.ncsu.edu/resolver/1840.16/204.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Jeong, Chang Woo. “Interfacial Phenomena on Polymetric Thin Films.” 2006. Web. 13 Apr 2021.

Vancouver:

Jeong CW. Interfacial Phenomena on Polymetric Thin Films. [Internet] [Thesis]. North Carolina State University; 2006. [cited 2021 Apr 13]. Available from: http://www.lib.ncsu.edu/resolver/1840.16/204.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Jeong CW. Interfacial Phenomena on Polymetric Thin Films. [Thesis]. North Carolina State University; 2006. Available from: http://www.lib.ncsu.edu/resolver/1840.16/204

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of New Mexico

30. Reed, Jamie. Assessment of the biocompatibility, stability, and suitability of novel thermoresponsive films for the rapid generation of cellular constructs.

Degree: Chemical and Biological Engineering, 2011, University of New Mexico

URL: http://hdl.handle.net/1928/12865

► Stimuli responsive polymers (SRP) are of great interest in the bioengineering community due to their use in applications such as drug delivery and tissue engineering.… (more)

▼ Stimuli responsive polymers (SRP) are of great interest in the bioengineering community due to their use in applications such as drug delivery and tissue engineering. One example of an SRP is poly(N-isopropyl acrylamide) or pNIPAM. This SRP has the capability of changing its conformation with a slight temperature change: adherent mammalian cells spontaneously release as a confluent cell sheet, which can be harvested for cell sheet engineering purposes. Since its initial use in 1968, many researchers have used pNIPAM to obtain a cell sheet composed of their cell type of interest. The differing protocols used for these diverse cell types, such as the conditions used for cell detachment, and the varying methods used for derivatizing substrates with pNIPAM have all led to conflicting reports on the utility of pNIPAM for cell sheet engineering purposes, as well as the relative cytotoxicity of the polymer. In this work, some of the key inconsistencies in the literature and previously unaddressed challenges when utilizing pNIPAM films are overcome for the purpose of rapid generation of cellular constructs, specifically spheroids. Pertinent characteristics of low temperature detachment are investigated for their effect on the kinetics of cell detachment. In addition, a novel, inexpensive method for obtaining pNIPAM films for mammalian cell detachment, combining pNIPAM with a sol-gel, was optimized and compared to plasma polymerization deposition. Furthermore, proper storage conditions (e.g. temperature and relative humidity) for these films were investigated to increase stability of the films for using tissue culture conditions. To increase the speed of generation of cell sheets, electrospun mats and hydrogels with a high surface area-to-volume ratio were developed. The result is a platform appropriate for the rapid formation of cellular constructs, such as engineered tissues and spheroids for cancer cell research. Advisors/Committee Members: Canavan, Heather, Hedberg-Dirk, Elizabeth, Freyer, James, Wandinger-Ness, Angela.

Subjects/Keywords: Thermoresponsive; pNIPAM; Biocompatibility; XPS; Surface analysis; Spheroids; Acrylimide – Thermal properties.; Attachment mechanisms (Biology); Acrylamide – Biocompatibility.; Bioengineering – Materials.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Reed, J. (2011). Assessment of the biocompatibility, stability, and suitability of novel thermoresponsive films for the rapid generation of cellular constructs. (Doctoral Dissertation). University of New Mexico. Retrieved from http://hdl.handle.net/1928/12865

Chicago Manual of Style (16^th Edition):

Reed, Jamie. “Assessment of the biocompatibility, stability, and suitability of novel thermoresponsive films for the rapid generation of cellular constructs.” 2011. Doctoral Dissertation, University of New Mexico. Accessed April 13, 2021. http://hdl.handle.net/1928/12865.

MLA Handbook (7^th Edition):

Reed, Jamie. “Assessment of the biocompatibility, stability, and suitability of novel thermoresponsive films for the rapid generation of cellular constructs.” 2011. Web. 13 Apr 2021.

Vancouver:

Reed J. Assessment of the biocompatibility, stability, and suitability of novel thermoresponsive films for the rapid generation of cellular constructs. [Internet] [Doctoral dissertation]. University of New Mexico; 2011. [cited 2021 Apr 13]. Available from: http://hdl.handle.net/1928/12865.

Council of Science Editors:

Reed J. Assessment of the biocompatibility, stability, and suitability of novel thermoresponsive films for the rapid generation of cellular constructs. [Doctoral Dissertation]. University of New Mexico; 2011. Available from: http://hdl.handle.net/1928/12865

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Open Access Theses and Dissertations