+publisher:"Vanderbilt University" +contributor:("Paul E. Laibinis")

Vanderbilt University

1. Erwin, William Robert. Shape Controlled Plasmonic Nanostructures for Light Harvesting Applications.

Degree: PhD, Chemical Engineering, 2017, Vanderbilt University

► In the search for economically feasible renewable energy sources, the conversion of solar energy into electricity is highly attractive to replace depleting fossil fuels and… (more)

▼ In the search for economically feasible renewable energy sources, the conversion of solar energy into electricity is highly attractive to replace depleting fossil fuels and mitigate high oil prices. While promising, solar harvesting technology does not compete with fossil fuels due to low power conversion efficiency (PCE) and high cost of processing, both of which remain a tremendous challenge. Through experiments and simulations, this PhD thesis investigates the use of metal nanostructures (MNS) for enhancement of PCE in photoelectrochemical solar cells and organic photovoltaics. In the presence of incident light, noble MNS support a localized surface plasmon resonance (LSPR) which are collective oscillations of the metal’s conduction electrons. Upon decoherence, LSPRs give rise to a collection of radiative and non-radiative effects, which can be harnessed to improve the light harvesting efficiency of various types of solar devices. In this work, we investigate the incorporation of colloidal plasmonic MNS into organic photovoltaics (OPVs) and photoelectrochemical water splitting electrodes as a route to improve PCE. A fundamental understanding of the interactions of plasmonic nanostructures with incident electromagnetic fields and subsequent field modulation in surrounding photovoltaic materials is paramount to achieve high PCE in solar devices. In particular this thesis examines how the shape and composition of MNS and the resulting radiative and non-radiative effects impacts the efficiency and charge transfer processes in solar devices. Our results show a 14x improvement in external quantum efficiency in photoelectrochemical water splitting with the incorporation of Au-Ag core-shell nanocrystals (Au-AgNCs) – 2.3x higher than enhancement achieved via incorporation of Au nanospheres. We attribute enhancement to improved radiative field enhancement achieved due to the “lightning rod effect,” resulting from nanostructure’s edges and corners. In OPVs, we observed an 11% enhancement in PCE via the incorporation of Au-AgNCs. Using numerical solvers to approximate solutions to Maxwell’s Equations, we learn that while the light capture in the absorbing layer is not increased, it is augmented such that charge transport is favorable, thus increasing PCE. Further, we explore the use of nanostructured electrodes for photoelectrochemical light harvesting. We find that it is possible to replace traditional platinum electodes with silicon-carbon hybrid electrodes to fabricate highly efficient platinum free dye-sensitized solar cells Advisors/Committee Members: Cary L. Pint, Ph.D. (committee member), Paul E. Laibinis, Ph.D. (committee member), G. Kane Jennings, Ph.D (committee member), Rizia Bardhan, Ph.D. (Committee Chair).

Subjects/Keywords: solar; plasmonics; nanotechnology

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APA (6^th Edition):

Erwin, W. R. (2017). Shape Controlled Plasmonic Nanostructures for Light Harvesting Applications. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/11171

Chicago Manual of Style (16^th Edition):

Erwin, William Robert. “Shape Controlled Plasmonic Nanostructures for Light Harvesting Applications.” 2017. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/11171.

MLA Handbook (7^th Edition):

Erwin, William Robert. “Shape Controlled Plasmonic Nanostructures for Light Harvesting Applications.” 2017. Web. 04 Mar 2021.

Vancouver:

Erwin WR. Shape Controlled Plasmonic Nanostructures for Light Harvesting Applications. [Internet] [Doctoral dissertation]. Vanderbilt University; 2017. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/11171.

Council of Science Editors:

Erwin WR. Shape Controlled Plasmonic Nanostructures for Light Harvesting Applications. [Doctoral Dissertation]. Vanderbilt University; 2017. Available from: http://hdl.handle.net/1803/11171

Vanderbilt University

2. Powers, Devon J. Electrospun Nanofiber Composite Membranes for Hydrogen/Air Fuel Cells.

Degree: PhD, Chemical Engineering, 2019, Vanderbilt University

URL: http://hdl.handle.net/1803/12023

► The fabrication of highly charged and highly durable proton-exchange membranes (PEMs) is a critical step toward improving the performance and lifetime of hydrogen fuel cells.… (more)

▼ The fabrication of highly charged and highly durable proton-exchange membranes (PEMs) is a critical step toward improving the performance and lifetime of hydrogen fuel cells. State of the art commercial PEMs from perfluorosulfonic acid ionomers suffer from excessive swelling when exposed to water. The present work’s objective was to investigate the use of electrospinning for the fabrication of highly charged (highly proton conductive) composite PEMs with low in-plane swelling. A series of membranes consisting of a low equivalent weight (i.e. highly charged) ionomer and an uncharged reinforcing polymer were prepared using dual fiber electrospinning (where ionomer and uncharged polymer are separately electrospun) and single fiber electrospinning (where ionomer and uncharged polymer are electrospun from a common solution). For the dual fiber membranes, the distribution of the uncharged reinforcing polymer in the thickness direction was varied (leading to a multi-layered membrane) or the average diameter of the reinforcing polymer was varied. For both the single fiber and dual fiber membranes, ionomers of varying equivalent weights were Incorporated into films with the same effective concentration of fixed charge groups. The dependence of membrane structure, ionomer equivalent weight and side chain chemistry on membrane conductivity and swelling was investigated, and the relevance of the results to fuel cell performance was discussed. The addition of a small amount of uncharged reinforcing polymer in an electrospun membrane led to a significant reduction in swelling, while conductivity generally followed a simple ionomer weight fraction mixing rule. Dual fiber membranes exhibited the best combination of properties, achieving low in-plane water swelling (as low as 4%) with high conductivities (up to 0.1 S/cm in 25°C water). Advisors/Committee Members: Scott Guelcher (committee member), Paul E. Laibinis (committee member), Shihong Lin (committee member), Peter N. Pintauro (Committee Chair).

Subjects/Keywords: Polymers; Fibers; Multi-Layer; Structure; Single Fiber; Dual Fiber

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APA (6^th Edition):

Powers, D. J. (2019). Electrospun Nanofiber Composite Membranes for Hydrogen/Air Fuel Cells. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/12023

Chicago Manual of Style (16^th Edition):

Powers, Devon J. “Electrospun Nanofiber Composite Membranes for Hydrogen/Air Fuel Cells.” 2019. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/12023.

MLA Handbook (7^th Edition):

Powers, Devon J. “Electrospun Nanofiber Composite Membranes for Hydrogen/Air Fuel Cells.” 2019. Web. 04 Mar 2021.

Vancouver:

Powers DJ. Electrospun Nanofiber Composite Membranes for Hydrogen/Air Fuel Cells. [Internet] [Doctoral dissertation]. Vanderbilt University; 2019. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/12023.

Council of Science Editors:

Powers DJ. Electrospun Nanofiber Composite Membranes for Hydrogen/Air Fuel Cells. [Doctoral Dissertation]. Vanderbilt University; 2019. Available from: http://hdl.handle.net/1803/12023

Vanderbilt University

3. Tovar, Trenton Marcus. Adsorption Equilibria and Mass Transfer in Porous Adsorbents.

Degree: PhD, Chemical Engineering, 2016, Vanderbilt University

URL: http://hdl.handle.net/1803/11623

► Adsorption is an interfacial phenomenon in which intermolecular forces between a molecule and a surface create an adsorbed phase with different properties than the bulk… (more)

▼ Adsorption is an interfacial phenomenon in which intermolecular forces between a molecule and a surface create an adsorbed phase with different properties than the bulk fluid. Variation in the adsorbed phase among different adsorbate and solid adsorbent pairs is the driving force for many gas-phase separations. To efficiently design these separation processes, detailed characterization of the adsorbed phase over a range of operating conditions is required. The two main characteristics of the adsorbed phase that need to be well understood are adsorption equilibria and mass transfer rates, i.e. how much and how fast molecules are adsorbed. The purpose of this work is to use fundamental principles of adsorption to measure and interpret adsorption equilibria and mass transfer rates in various systems of interest. A concentration-swing frequency response (CSFR) method was used to measure mass transfer rates of a series of hydrocarbons in BPL activated carbon. Hydrocarbons with different ring and branched structures were used to test for steric effects on diffusion in the amorphous adsorbent. A correlation between rigid-ring structures and lower diffusivity was found. CSFR was also used to measure diffusion rates of CO2 in large single crystals of Cu-BTC, a metal-organic framework (MOF). Many MOFs have been studied as adsorbents for carbon capture and sequestration, but diffusion rates in the literature are scarce. The single crystal morphology of Cu-BTC allowed accurate measurements of micropore diffusion coefficients. Mass transfer rates were also measured on bidisperse pellets of a highly stable MOF, UiO-66, for CO2 and ethane. Macropore diffusion was determined to be the controlling resistance for both adsorbates. Volumetric methods were used to measure high pressure oxygen isotherms on a series of MOFs. MOFs with coordinatively unsaturated Cu metal sites were found to be promising candidates for oxygen storage, with capacities greater than current state of the art adsorbents. Finally, novel adsorbents were synthesized for a CO2 scrubber in a rebreather apparatus. The challenge for these adsorbents was obtaining high CO2 capacities at ambient temperatures, despite low CO2 partial pressures in water saturated conditions, while preventing mass transfer limitations. Advisors/Committee Members: Kenneth A. Debelak (committee member), Paul E. Laibinis (committee member), Eugene J. LeBoeuf (committee member), M. Douglas LeVan (Committee Chair).

Subjects/Keywords: Adsorption; mass transfer; metal-organic framework

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APA (6^th Edition):

Tovar, T. M. (2016). Adsorption Equilibria and Mass Transfer in Porous Adsorbents. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/11623

Chicago Manual of Style (16^th Edition):

Tovar, Trenton Marcus. “Adsorption Equilibria and Mass Transfer in Porous Adsorbents.” 2016. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/11623.

MLA Handbook (7^th Edition):

Tovar, Trenton Marcus. “Adsorption Equilibria and Mass Transfer in Porous Adsorbents.” 2016. Web. 04 Mar 2021.

Vancouver:

Tovar TM. Adsorption Equilibria and Mass Transfer in Porous Adsorbents. [Internet] [Doctoral dissertation]. Vanderbilt University; 2016. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/11623.

Council of Science Editors:

Tovar TM. Adsorption Equilibria and Mass Transfer in Porous Adsorbents. [Doctoral Dissertation]. Vanderbilt University; 2016. Available from: http://hdl.handle.net/1803/11623

Vanderbilt University

4. Escobar, Carlos Andres. Surface-Initiated Ring-Opening Metathesis Polymerization: A Versatile Route to Produce Novel Materials and Biomimetic Coatings.

Degree: PhD, Chemical Engineering, 2014, Vanderbilt University

URL: http://hdl.handle.net/1803/10466

► The modification of materials and surfaces with fluorocarbons enables ultralow surface energies in the development of numerous applications of cutting-edge science and technology. The use… (more)

▼ The modification of materials and surfaces with fluorocarbons enables ultralow surface energies in the development of numerous applications of cutting-edge science and technology. The use of partially fluorinated materials offers advantages in terms of cost and synthetic flexibility, and in some cases, performance, when compared to all–fluorocarbon materials. This research employs a surface-initiated polymerization (SIP), namely surface-initiated ring-opening metathesis polymerization (SI-ROMP), to grow partially fluorinated coatings with critical surface tensions as low as 9 mN/m that establish new standards in thickness with tremendous control over microscale surface texturing. SIP techniques provide robust chemisorption, diverse chemical functionality, control over film growth, and the ability to uniformly coat planar and non-planar surfaces. Although SIP methods have been previously used to deposit partially fluorinated films, the ability to grow such films with thicknesses above a few micrometers, with controlled textures, or within nanoporous materials has not been demonstrated prior to this work. Accordingly, this dissertation focuses on: (1) the fabrication and characterization of novel partially fluorinated/inorganic composites by employing SI-ROMP within nanoporous architectures to create membranes with tunable wettability and ion transport; (2) the amplification of the SIP of partially fluorinated polymer films to fabricate specialty coatings that yield thicknesses from 4 – 12 µm in as little as 15 min of polymerization. Remarkably, these films exhibit resistance against ion transport in excess of 10 GΩ•cm², which is the highest value ever reported for SIP films; and the development of a new SIP-based approach to (3) fabricate microscale surface features with height modulation and to (4) reproduce the complex surface topographies of superhydrophobic natural surfaces onto solid supports. This process enables the preparation of microtextured films and novel biomimetic coatings that reproduce superhydrophobic plant leaves, and could radically impact applications such as self-cleaning surfaces and chemical- and corrosion-resistant coatings. Advisors/Committee Members: Scott A. Guelcher (committee member), Paul E. Laibinis (committee member), Eva M. Harth (committee member), G. Kane Jennings (Committee Chair).

Subjects/Keywords: Membranes; Protective Coatings; SI-ROMP; Partially Fluorinated; Superhydrophobic Coatings

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APA (6^th Edition):

Escobar, C. A. (2014). Surface-Initiated Ring-Opening Metathesis Polymerization: A Versatile Route to Produce Novel Materials and Biomimetic Coatings. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/10466

Chicago Manual of Style (16^th Edition):

Escobar, Carlos Andres. “Surface-Initiated Ring-Opening Metathesis Polymerization: A Versatile Route to Produce Novel Materials and Biomimetic Coatings.” 2014. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/10466.

MLA Handbook (7^th Edition):

Escobar, Carlos Andres. “Surface-Initiated Ring-Opening Metathesis Polymerization: A Versatile Route to Produce Novel Materials and Biomimetic Coatings.” 2014. Web. 04 Mar 2021.

Vancouver:

Escobar CA. Surface-Initiated Ring-Opening Metathesis Polymerization: A Versatile Route to Produce Novel Materials and Biomimetic Coatings. [Internet] [Doctoral dissertation]. Vanderbilt University; 2014. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/10466.

Council of Science Editors:

Escobar CA. Surface-Initiated Ring-Opening Metathesis Polymerization: A Versatile Route to Produce Novel Materials and Biomimetic Coatings. [Doctoral Dissertation]. Vanderbilt University; 2014. Available from: http://hdl.handle.net/1803/10466

Vanderbilt University

5. Thompson, Matthew White. MOLECULAR SIMULATION OF IONIC LIQUIDS: EFFECTS OF SOLVATION, HUMIDIFICATION, AND CONFINEMENT.

Degree: PhD, Chemical Engineering, 2019, Vanderbilt University

URL: http://hdl.handle.net/1803/14153

► Ionic liquids are organic salts that exist in the liquid state near ambient conditions. They exhibit remarkable physical properties, including low vapor pressure and high… (more)

▼ Ionic liquids are organic salts that exist in the liquid state near ambient conditions. They exhibit remarkable physical properties, including low vapor pressure and high thermal, chemical, and electrochemical stability, and application-specific tunability. They hold great potential for a number of applications across several industries, such as electrochemical energy storage, cellulose processing, and separations. This dissertation primarily focuses on their use in electrochemical capacitors, or supercapacitors. These are energy storage devices that store energy by physical adsorption of ions at charged interfaces with no chemical reactions. As a result, they exhibit great power density and lower energy density than batteries - the storage and delivery of energy is much quicker, but the amount of stored energy is lower. Supercapacitors are used in niche applications, such as regenerative braking in automobiles, but need to exhibit higher energy and power density to become achieve broader adoption. This dissertation explores some potential means by which the performance of supercapacitors can be increased. One proposed technique is dissolving ionic liquids in organic solvents, by which ion mobility is greatly enhanced and, as a result, power density increased. Fundamental connections between solvent properties and ionic liquid structure and dynamics, however, are not well-understood. We have employed a computational screening study to consider 400 mixtures of ionic liquids in organic solvents. Trends between solvent properties, mixture properties, and their effects on energy storage applications, are discussed. The focus of this talk will be the solvent study, however other topics, including the use of porous carbons and novel 2-D materials and the effects of humidity and nanoconfinement will briefly be discussed. Advisors/Committee Members: D. Greg Walker (committee member), Clare McCabe (committee member), Paul E. Laibinis (committee member), Peter T. Cummings (Committee Chair).

Subjects/Keywords: molecular simulation; molecular dynamics; computational screening; ionic liquids; electrolytes

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APA (6^th Edition):

Thompson, M. W. (2019). MOLECULAR SIMULATION OF IONIC LIQUIDS: EFFECTS OF SOLVATION, HUMIDIFICATION, AND CONFINEMENT. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/14153

Chicago Manual of Style (16^th Edition):

Thompson, Matthew White. “MOLECULAR SIMULATION OF IONIC LIQUIDS: EFFECTS OF SOLVATION, HUMIDIFICATION, AND CONFINEMENT.” 2019. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/14153.

MLA Handbook (7^th Edition):

Thompson, Matthew White. “MOLECULAR SIMULATION OF IONIC LIQUIDS: EFFECTS OF SOLVATION, HUMIDIFICATION, AND CONFINEMENT.” 2019. Web. 04 Mar 2021.

Vancouver:

Thompson MW. MOLECULAR SIMULATION OF IONIC LIQUIDS: EFFECTS OF SOLVATION, HUMIDIFICATION, AND CONFINEMENT. [Internet] [Doctoral dissertation]. Vanderbilt University; 2019. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/14153.

Council of Science Editors:

Thompson MW. MOLECULAR SIMULATION OF IONIC LIQUIDS: EFFECTS OF SOLVATION, HUMIDIFICATION, AND CONFINEMENT. [Doctoral Dissertation]. Vanderbilt University; 2019. Available from: http://hdl.handle.net/1803/14153

Vanderbilt University

6. Njoroge, Ian Gitata. Poly(Ionic Liquid) Thin Films via Surface-Initiated Ring-Opening Metathesis Polymerization.

Degree: PhD, Chemical Engineering, 2017, Vanderbilt University

URL: http://hdl.handle.net/1803/14000

► Ionic liquids (ILs) are organic salts that are liquid at or near room temperature (i.e. below 100 ^◦C). They possess unique materials and solvent properties… (more)

▼ Ionic liquids (ILs) are organic salts that are liquid at or near room temperature (i.e. below 100 ^◦C). They possess unique materials and solvent properties that have led to their use in multiple applications. Poly(ionic liquids) (PILs) refer to a special type of polyelectrolyte that carries an IL species in each of the polymer repeating units. PILs offer advantages over ILs in enhanced mechanical stability, and improved processability, durability and spatial control over the IL moieties. The ability to generate surface-tethered polymer films with IL functionality as side chains can enable coatings with versatile and tailorable properties. This dissertation describes the preparation and characterization of surface-polymerized ILs. Surface-tethered poly(ionic liquid) (PIL) films were prepared via surface-initiated ring-opening metathesis polymerization (SI-ROMP) of ionic liquid-tethered monomers on gold, silicon, and glass substrates and were shown to be adaptive to their anionic environment. A simple anion exchange of PIL films with aqueous solutions containing a binary mixture anions led to the formation of random copolymer PIL films, that offered a continuous tuning of film properties between the extremes of the two homopolymers incorporating the anions present in the copolymer films. For surface-tethered PIL films on gold substrates, anion exchange with certain anions such as triflate, led to the desorption of the PIL films from the surface due to entropic effects and an increase in the glass transition temperature of the films. Part of the dissertation examines polydicyclopentadiene (pDCPD), which is a rigid, cross-linked polymer with excellent impact strength, high modulus, and high chemical resistance. Commercially used for automotive panels and sporting goods, pDCPD has been experimentally explored for a broad range of applications including ballistic protection. While bulk pDCPD has broad commercial impact, the ability to prepare surface-immobilized polymer films of pDCPD, especially with minimal environmental impact, could lead to tough, impact- resistant surfaces with numerous applications. Surface-tethered pDCPD films were prepared on gold and silicon substrates via a novel SI-ROMP with monomer in the vapor space. The choice of ROMP catalyst was an important factor when SI-ROMP was conducted on different substrates.<p/> Advisors/Committee Members: Paul E. Laibinis, Ph.D. (committee member), Clare M. M (committee member), Douglas E. Adams (committee member), G. Kane Jennings, Ph.D. (Committee Chair).

Subjects/Keywords: Thin Films; Ionic Liquids; Polymeric Ionic Liquids; PILs; Surface-Tethered; Dicyclopentadiene; Polydicyclopentadiene; pDCPD; Ring-Opening; Metathesis; Polymerization; ROMP; SI-ROMP; Grubb's Catalyst

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

APA (6^th Edition):

Njoroge, I. G. (2017). Poly(Ionic Liquid) Thin Films via Surface-Initiated Ring-Opening Metathesis Polymerization. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/14000

Chicago Manual of Style (16^th Edition):

Njoroge, Ian Gitata. “Poly(Ionic Liquid) Thin Films via Surface-Initiated Ring-Opening Metathesis Polymerization.” 2017. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/14000.

MLA Handbook (7^th Edition):

Njoroge, Ian Gitata. “Poly(Ionic Liquid) Thin Films via Surface-Initiated Ring-Opening Metathesis Polymerization.” 2017. Web. 04 Mar 2021.

Vancouver:

Njoroge IG. Poly(Ionic Liquid) Thin Films via Surface-Initiated Ring-Opening Metathesis Polymerization. [Internet] [Doctoral dissertation]. Vanderbilt University; 2017. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/14000.

Council of Science Editors:

Njoroge IG. Poly(Ionic Liquid) Thin Films via Surface-Initiated Ring-Opening Metathesis Polymerization. [Doctoral Dissertation]. Vanderbilt University; 2017. Available from: http://hdl.handle.net/1803/14000

Vanderbilt University

7. Wang, Zhangxin. Fouling and Wetting in Membrane Distillation: Mechanisms and Mitigation Strategies.

Degree: PhD, Environmental Engineering, 2018, Vanderbilt University

URL: http://hdl.handle.net/1803/14224

► Growing water scarcity and rising environmental awareness have posed stricter regulations on industrial wastewater disposal. Since many types of industrial wastewater contains significant amount of… (more)

▼ Growing water scarcity and rising environmental awareness have posed stricter regulations on industrial wastewater disposal. Since many types of industrial wastewater contains significant amount of salts, desalination is a necessity for responsible wastewater disposal. Membrane distillation (MD) is an emerging thermal desalination technology using a microporous hydrophobic membrane. Compared to reverse osmosis, the state-in-the-art desalination technology, MD has several advantages including the capability of utilizing low-grade waste heat, availability for treating hypersaline brines, low capital cost, and small footprint. However, the adoption of MD in industry is still limited mainly due to certain constraints with conventional hydrophobic membranes, in particular membrane fouling and wetting. Membrane fouling refers to the blockage of membrane pores by hydrophobic contaminants that are rich in certain industrial wastewater. Membrane wetting refers to the penetration of membrane pores by salty solution, which undermines salt rejection. Membrane wetting usually occurs in the presence of low-surface-tension water-miscible liquids (e.g. alcohols) or amphiphilic molecules (e.g. surfactants) in feed waters. In this dissertation, we elucidated the mechanisms of membrane fouling and wetting, and provided corresponding mitigation strategies. For membrane fouling, we studied the impacts of surface wetting property and surface charge on the fouling resistance of the MD membranes, and thereby provided guidance for the construction of fouling-resistance membranes. For membrane wetting, we firstly developed a novel impedance-based method for monitoring dynamic pore wetting. With this impedance-based method, we compared membrane pore wetting induced by different wetting agents of different nature and elucidated the different wetting mechanisms. Furthermore, we developed a mathematical model to predict the breakthrough time of pore wetting induced by surfactants, which can correctly predict the effects of operating conditions and surfactant species. Finally, with the fundamental understandings of fouling and wetting, we analyzed the strategies for sustaining robust MD operations with different types of feed waters using MD membranes with different wettability. Advisors/Committee Members: Florence Sanchez (committee member), Alan Bowers (committee member), Paul E. Laibinis (committee member), G. Kane Jennings (committee member), Shihong Lin (Committee Chair).

Subjects/Keywords: wetting mitigation; fouling mitigation; membrane wetting; membrane distillation; membrane fouling

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APA (6^th Edition):

Wang, Z. (2018). Fouling and Wetting in Membrane Distillation: Mechanisms and Mitigation Strategies. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/14224

Chicago Manual of Style (16^th Edition):

Wang, Zhangxin. “Fouling and Wetting in Membrane Distillation: Mechanisms and Mitigation Strategies.” 2018. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/14224.

MLA Handbook (7^th Edition):

Wang, Zhangxin. “Fouling and Wetting in Membrane Distillation: Mechanisms and Mitigation Strategies.” 2018. Web. 04 Mar 2021.

Vancouver:

Wang Z. Fouling and Wetting in Membrane Distillation: Mechanisms and Mitigation Strategies. [Internet] [Doctoral dissertation]. Vanderbilt University; 2018. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/14224.

Council of Science Editors:

Wang Z. Fouling and Wetting in Membrane Distillation: Mechanisms and Mitigation Strategies. [Doctoral Dissertation]. Vanderbilt University; 2018. Available from: http://hdl.handle.net/1803/14224

Vanderbilt University

8. Self, Ethan Craig. Electrospun Particle/Polymer Fiber Mat Electrodes for Li-ion Batteries.

Degree: PhD, Chemical Engineering, 2017, Vanderbilt University

URL: http://hdl.handle.net/1803/15340

► Since their commercial debut in 1991, Li-ion batteries (LIBs) have revolutionized the functionality of portable electronic devices, and the LIB industry continues to grow today… (more)

▼ Since their commercial debut in 1991, Li-ion batteries (LIBs) have revolutionized the functionality of portable electronic devices, and the LIB industry continues to grow today due emerging applications such as electric vehicle propulsion. Despite the extraordinary success of LIBs, many devices are still limited by battery performance, and thus new batteries with higher energy density, faster rechargeability, and longer cycle life must be developed to satisfy the ever-increasing demands of consumers. This dissertation details the fabrication and characterization of electrospun particle/polymer fiber mats as LIB electrodes, including: (i) anodes containing titania nanoparticles, carbon powder, and poly(acrylic acid) (TiO2/C/PAA), (ii) anodes containing carbon powder and poly(vinylidene fluoride) (C/PVDF), (iii) anodes containing Si nanoparticles, carbon powder, and PAA (Si/C/PAA), and (iv) cathodes containing LiCoO2 nanoparticles, carbon powder, and PVDF (LiCoO2/C/PVDF). The composition, thickness, fiber volume fraction, and fiber interconnectivity of electrospun mats can be easily controlled to achieve high capacities at fast charge/discharge rates. An electrospun TiO2/C/PAA anode with a thickness of 600 µm had an areal capacity of 0.97 mAh cm-2 at 2C which is much greater than that of a slurry cast anode of the same composition and loading (0.53 mAh cm-2). Likewise, a C/PVDF anode with a fiber volume fraction of 0.85 had a high volumetric capacity of 55 mAh cm-3 at 2C compared to only 27 mAh cm-3 for a conventional slurry cast graphite anode. Si/C/PAA fiber mat anodes had extremely high gravimetric, areal, and volumetric capacities of 1,484 mAh g-1, 4.5 mAh cm-2, and 750 mAh cm-3, respectively. C/LiCoO2 and Si/LiCoO2 full cells prepared with an electrospun anode and electrospun cathode had high specific energy densities of 150 and 270 Wh kg-1, respectively, which are among the highest values reported in the literature to date. The excellent performance of electrospun particle/polymer fiber mat electrodes is attributed to their: (i) large electrode/electrolyte interfacial areas, (ii) short Li+ transport pathways, and (iii) good electrolyte infiltration throughout the intra- and interfiber void space of the mats. These results demonstrate that the intelligent organization of electroactive powders into fiber mat electrodes can enhance Li+ transport rates and improve LIB performance. Advisors/Committee Members: Bridget R. Rogers (committee member), Cary L. Pint (committee member), Paul E. Laibinis (committee member), Peter N. Pintauro (Committee Chair).

Subjects/Keywords: Porous Electrode; Volumetric Capacity; Areal Capacity; Nanofibers; Electrospinning; Li-ion Batteries

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APA (6^th Edition):

Self, E. C. (2017). Electrospun Particle/Polymer Fiber Mat Electrodes for Li-ion Batteries. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/15340

Chicago Manual of Style (16^th Edition):

Self, Ethan Craig. “Electrospun Particle/Polymer Fiber Mat Electrodes for Li-ion Batteries.” 2017. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/15340.

MLA Handbook (7^th Edition):

Self, Ethan Craig. “Electrospun Particle/Polymer Fiber Mat Electrodes for Li-ion Batteries.” 2017. Web. 04 Mar 2021.

Vancouver:

Self EC. Electrospun Particle/Polymer Fiber Mat Electrodes for Li-ion Batteries. [Internet] [Doctoral dissertation]. Vanderbilt University; 2017. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/15340.

Council of Science Editors:

Self EC. Electrospun Particle/Polymer Fiber Mat Electrodes for Li-ion Batteries. [Doctoral Dissertation]. Vanderbilt University; 2017. Available from: http://hdl.handle.net/1803/15340

Vanderbilt University

9. Zhao, Yiliang. Engineering Porous Silicon Photonic Structures towards Fast and Reliable Optical Biosensing.

Degree: PhD, Interdisciplinary Materials Science, 2017, Vanderbilt University

URL: http://hdl.handle.net/1803/11255

► Porous silicon, a nanostructured material formed by electrochemical etching of a silicon substrate, is an ideal candidate for constructing optical biosensors due to its large… (more)

▼ Porous silicon, a nanostructured material formed by electrochemical etching of a silicon substrate, is an ideal candidate for constructing optical biosensors due to its large internal surface area, straightforward fabrication, and tunable optical properties that can be exploited to form numerous photonic structures. A major challenge for porous silicon biosensors is its reactive surface that is highly susceptible to oxidation and corrosion in an aqueous environment. In DNA sensing applications, porous silicon corrosion can mask the DNA binding signal as the dissolution of porous silicon is accelerated by the negative charges on the phosphate backbone of the DNA molecules. This corrosion process can be mitigated through surface passivation of porous silicon and the use of charge neutral peptide nucleic acid molecules as capturing probes for DNA targets. Complete mitigation can be achieved by additionally introducing Mg2+ ions to shield the negative charges on the DNA targets. Another key challenge facing porous silicon biosensors is the inefficient analyte transport through nanopores, which can be as slow as a few molecules per pore per second for molecules whose size approaches that of the pore opening. An open-ended porous silicon membrane is demonstrated to overcome the mass transport challenge by allowing analytes to flow through the pores in microfluidic-based assays. The flow-through approach for biosensing using porous silicon membranes enables a 6-fold improvement in sensor response time compared to closed-ended, flow-over porous silicon sensors when detecting high molecular weight analytes (e.g., streptavidin). For small analytes, little to no sensor performance improvement is observed as the closed-ended porous silicon films do not suffer significant mass transport challenges with these molecules. Experimental results and finite element method simulations also indicate that the flow-through scheme enables more reasonable response times for the detection of dilute analytes and reduces the volume of solution required for analysis. Overall, the improvement of surface stabilization and analyte transport efficiency in porous silicon photonic structures opens the door to a fast and reliable optical biosensing platform. Advisors/Committee Members: Dmitry Koktysh (committee member), Deyu Li (committee member), Yaqiong Xu (committee member), Paul E. Laibinis (Committee Chair), Sharon M. Weiss (Committee Chair).

Subjects/Keywords: dna sensor; membrane; optical biosensor; porous silicon; flow-through; kinetics

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APA (6^th Edition):

Zhao, Y. (2017). Engineering Porous Silicon Photonic Structures towards Fast and Reliable Optical Biosensing. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/11255

Chicago Manual of Style (16^th Edition):

Zhao, Yiliang. “Engineering Porous Silicon Photonic Structures towards Fast and Reliable Optical Biosensing.” 2017. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/11255.

MLA Handbook (7^th Edition):

Zhao, Yiliang. “Engineering Porous Silicon Photonic Structures towards Fast and Reliable Optical Biosensing.” 2017. Web. 04 Mar 2021.

Vancouver:

Zhao Y. Engineering Porous Silicon Photonic Structures towards Fast and Reliable Optical Biosensing. [Internet] [Doctoral dissertation]. Vanderbilt University; 2017. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/11255.

Council of Science Editors:

Zhao Y. Engineering Porous Silicon Photonic Structures towards Fast and Reliable Optical Biosensing. [Doctoral Dissertation]. Vanderbilt University; 2017. Available from: http://hdl.handle.net/1803/11255

Vanderbilt University

10. Klein, Christoph Thomas. Towards rational design of nanoscale lubricants and elucidation of the hydration lubrication mechanism using molecular simulation.

Degree: PhD, Chemical Engineering, 2017, Vanderbilt University

URL: http://hdl.handle.net/1803/14557

► Nanoscale devices featuring surfaces in sliding contact are found in applications ranging from biocompatible materials for joint replacement to the next generation of hard disk… (more)

▼ Nanoscale devices featuring surfaces in sliding contact are found in applications ranging from biocompatible materials for joint replacement to the next generation of hard disk drive technologies. While several approaches to lubricating such systems have been proposed, as well as successfully implemented, we lack the ability to properly explore this design space. In this dissertation are described 1) a collection of tools designed to enable large scale screening of soft materials across chemical parameter space and 2) the application of these tools to studying surface functionalized materials for use in nanoscale lubrication systems. The core tool, mBuild, generates starting configurations for simulations by minimizing or even eliminating the need to explicitly translate and orient components when building systems - users simply state which components to connect. This approach enables users to programmatically vary parameters for a family of systems (e.g., polymer chain length) or interchange individual components (e.g., polymer type), while still employing the same general framework. mBuild integrates with the Foyer tool for cataloging and applying force fields to molecular systems. Foyer provides a force field and simulator agnostic method for defining parameter usage that relies upon SMARTS based annotations of chemical context, providing both human and machine readable documentation of parameter usage, which also aids in the dissemination of force fields. We demonstrate the utility and flexibility of our tool chain by screening the frictional properties of several families of monolayers. The tool chain is also employed to study the molecular origins of the experimentally hypothesized hydration lubrication mechanism as it is manifested in poly(2-methacryloyloxyethyl phosphorylcholine), or pMPC, based materials. Surface bound films of this biocompatible polymer have been shown experimentally to produce tribological properties that surpass those of the human synovial joint and are being developed for use in artificial joints. The mechanism by which such materials are thought to provide ultra-low friction coefficients has been termed “hydration lubrication” . The work presented herein lends strong support to the hypothesis that hydration lubrication is manifested in pMPC systems and additionally that the phosphorus bearing moiety is responsible for enabling this mechanism while the choline group may serve to stabilize the overall brush structure thus giving rise to the remarkable durability of the experimentally grown brush layers. Advisors/Committee Members: Paul D. Sheldon (committee member), John T. Wilson (committee member), Paul E. Laibinis (committee member), Peter T. Cummings (Committee Chair), Clare McCabe (Committee Chair).

Subjects/Keywords: molecular dynamics; tribology; reproducibility

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APA (6^th Edition):

Klein, C. T. (2017). Towards rational design of nanoscale lubricants and elucidation of the hydration lubrication mechanism using molecular simulation. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/14557

Chicago Manual of Style (16^th Edition):

Klein, Christoph Thomas. “Towards rational design of nanoscale lubricants and elucidation of the hydration lubrication mechanism using molecular simulation.” 2017. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/14557.

MLA Handbook (7^th Edition):

Klein, Christoph Thomas. “Towards rational design of nanoscale lubricants and elucidation of the hydration lubrication mechanism using molecular simulation.” 2017. Web. 04 Mar 2021.

Vancouver:

Klein CT. Towards rational design of nanoscale lubricants and elucidation of the hydration lubrication mechanism using molecular simulation. [Internet] [Doctoral dissertation]. Vanderbilt University; 2017. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/14557.

Council of Science Editors:

Klein CT. Towards rational design of nanoscale lubricants and elucidation of the hydration lubrication mechanism using molecular simulation. [Doctoral Dissertation]. Vanderbilt University; 2017. Available from: http://hdl.handle.net/1803/14557

Vanderbilt University

11. Yang, Alexander Hao. Molecular Simulation Studies of Lipid Bilayers and Biomolecular Coatings for Water Barrier and Biocompatibility Purposes.

Degree: PhD, Chemical Engineering, 2020, Vanderbilt University

URL: http://hdl.handle.net/1803/10442

► Lipid bilayers occupying the gel and fluid phases are examined using molecular dynamics simulation. Molecular dynamics simulations of gel-phase bilayers comprised of varying compositions of… (more)

Subjects/Keywords: molecular simulation; lipid bilayer; molecular dynamics

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APA (6^th Edition):

Yang, A. H. (2020). Molecular Simulation Studies of Lipid Bilayers and Biomolecular Coatings for Water Barrier and Biocompatibility Purposes. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/10442

Chicago Manual of Style (16^th Edition):

Yang, Alexander Hao. “Molecular Simulation Studies of Lipid Bilayers and Biomolecular Coatings for Water Barrier and Biocompatibility Purposes.” 2020. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/10442.

MLA Handbook (7^th Edition):

Yang, Alexander Hao. “Molecular Simulation Studies of Lipid Bilayers and Biomolecular Coatings for Water Barrier and Biocompatibility Purposes.” 2020. Web. 04 Mar 2021.

Vancouver:

Yang AH. Molecular Simulation Studies of Lipid Bilayers and Biomolecular Coatings for Water Barrier and Biocompatibility Purposes. [Internet] [Doctoral dissertation]. Vanderbilt University; 2020. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/10442.

Council of Science Editors:

Yang AH. Molecular Simulation Studies of Lipid Bilayers and Biomolecular Coatings for Water Barrier and Biocompatibility Purposes. [Doctoral Dissertation]. Vanderbilt University; 2020. Available from: http://hdl.handle.net/1803/10442

Vanderbilt University

12. Tedjo, Chrysanty. Controlling protein-surface interactions in chromatography using mixed self-assembled monolayers.

Degree: PhD, Chemical Engineering, 2011, Vanderbilt University

URL: http://hdl.handle.net/1803/11289

► High performance liquid chromatography (HPLC) has become an essential tool in biotechnology. Numerous proteins have been separated by HPLC for analytical and preparative separation purposes.… (more)

▼ High performance liquid chromatography (HPLC) has become an essential tool in biotechnology. Numerous proteins have been separated by HPLC for analytical and preparative separation purposes. The main challenge in protein chromatography is the ability to isolate the protein of interest in its active form with high purity. The goal of this research is to provide a generic chromatographic approach for separating proteins efficiently with high retention of their biological activity. Here, I utilized mixed self self-assembled monolayers (SAMs) of Cl3Si(CH2)11(OCH2CH2)3OCH3 (EG3OMe) and n-octyltrichlorosilane (C8) to modulate protein-silica support interactions in a controlled manner. The oligo(ethylene glycol) tail groups in the EG3OMe SAM display a surface hydrophilicity that minimizes interactions with proteins. The C8 SAM displays a hydrophobic surface that adsorbs proteins. With mixed SAMs, the wetting properties of their surface and their level of interactions with proteins can be controlled. Mixed SAMs of EG3OMe and C8 were deposited on SiO2/Si substrates and silica supports. Analysis using x-ray photoelectron spectroscopy showed that the surface compositions of mixed SAM-coated particles were similar to those of mixed SAMs formed on flat substrates. The critical surface tensions of the mixed SAM-coated silica particles, estimated by a developed flotation method, were similar to those of the same mixed SAMs on SiO2/Si substrates, as measured using contact angle goniometry. The performances of these mixed SAM coated-supports were examined in a HPLC system using several model proteins. The results from chromatographic experiments showed that protein retention and separation in a chromatographic column was controllable by selecting the appropriate level of column hydrophobicity and the concentration of salt in the mobile phase. Analysis of protein mass recoveries after chromatography revealed that the rate loss of protein in the column was primarily a function of the protein residence time. The described methods provide a systematic way for controlling protein retention during chromatography by tuning the hydrophobicity of the support. With proper selection, a surface hydrophobicity can be produced so that a protein can be effectively retained by a support without resulting in its permanent loss during chromatography. Advisors/Committee Members: G. Kane Jennings (committee member), M. Douglas LeVan (committee member), Scott A. Guelcher (committee member), David E. Cliffel (committee member), Paul E. Laibinis (Committee Chair).

Subjects/Keywords: self-assembled monolayers; chromatography; protein separation

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APA (6^th Edition):

Tedjo, C. (2011). Controlling protein-surface interactions in chromatography using mixed self-assembled monolayers. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/11289

Chicago Manual of Style (16^th Edition):

Tedjo, Chrysanty. “Controlling protein-surface interactions in chromatography using mixed self-assembled monolayers.” 2011. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/11289.

MLA Handbook (7^th Edition):

Tedjo, Chrysanty. “Controlling protein-surface interactions in chromatography using mixed self-assembled monolayers.” 2011. Web. 04 Mar 2021.

Vancouver:

Tedjo C. Controlling protein-surface interactions in chromatography using mixed self-assembled monolayers. [Internet] [Doctoral dissertation]. Vanderbilt University; 2011. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/11289.

Council of Science Editors:

Tedjo C. Controlling protein-surface interactions in chromatography using mixed self-assembled monolayers. [Doctoral Dissertation]. Vanderbilt University; 2011. Available from: http://hdl.handle.net/1803/11289

Vanderbilt University

13. Zubair, Faizan. Pre-fabricated Surfaces for Assessment of Spatial Resolution and Proteomic Analysis of Tissue Samples using Imaging Mass Spectrometry.

Degree: PhD, Chemical Engineering, 2016, Vanderbilt University

URL: http://hdl.handle.net/1803/12500

► Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) is an enabling tool in medical and biological research. From a single experiment, hundreds of biomolecules can be… (more)

▼ Matrix-assisted laser desorption/ionization imaging mass spectrometry (MALDI-IMS) is an enabling tool in medical and biological research. From a single experiment, hundreds of biomolecules can be spatially mapped on a tissue section. A key bottleneck remains the time-consuming sample preparation that requires several hours for each tissue specimen. Current methods employ robotic spotters to serially deposit enzyme and matrix in spatially discrete regions on the tissue. This work develops an alternative using targets pre-coated with trypsin and a MALDI matrix, where the tissue is mounted onto these coated surfaces and then undergoes chemical transformation and incubation to allow digestion of its proteins. Tryptic fragments from proteins including myelin basic protein, PEP-19, neurogranin, and brain acid soluble protein 1 have been successfully imaged by this approach. Further, this pre-coated method provides a standardized target offering reduced sample preparation time and improved spatial resolution down to 75 µm. A second goal was to fabricate synthetic patterns as imaging standard for evaluating instrument performance and spatial resolution. A standard reticle slide was prepared using lithographic and self-assembly techniques. A PDMS stamp functionalized a gold surface with hexadecanethiol to drive the self-assembly of crystal violet into a specified pattern. The developed reticle slide allowed accurate measurement of laser spot sizes under operating conditions, determination of the positional accuracy of laser on a target, and a comparison of the reproducibility and accuracy of scans across the targets. Together with developed criteria for analysis, an objective assessment of spatial resolution for MALDI-IMS is provided. These two efforts provide greater reliability for MALDI-IMS by reducing variability. The pre-coated slides streamline the sample preparation for tissue specimen and reduce the burden of sample preparation on the user. The reticle slides allow routine evaluation of instrumentation performance and spatial resolution. Together, these methods can ensure standardized and reproducible performance to aid adoption of MALDI IMS in the clinical environment. Advisors/Committee Members: John A. Mclean (committee member), Richard M. Caprioli (committee member), Matthew J. Lang (committee member), G. Kane Jennings (committee member), Paul E. Laibinis (Committee Chair).

Subjects/Keywords: Reticle; Enzymatic Digestion; Matrix Pre-coated Substrates; MALDI Imaging; Enzyme Pre-coated Substrates; Imaging Rat Brain

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APA (6^th Edition):

Zubair, F. (2016). Pre-fabricated Surfaces for Assessment of Spatial Resolution and Proteomic Analysis of Tissue Samples using Imaging Mass Spectrometry. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/12500

Chicago Manual of Style (16^th Edition):

Zubair, Faizan. “Pre-fabricated Surfaces for Assessment of Spatial Resolution and Proteomic Analysis of Tissue Samples using Imaging Mass Spectrometry.” 2016. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/12500.

MLA Handbook (7^th Edition):

Zubair, Faizan. “Pre-fabricated Surfaces for Assessment of Spatial Resolution and Proteomic Analysis of Tissue Samples using Imaging Mass Spectrometry.” 2016. Web. 04 Mar 2021.

Vancouver:

Zubair F. Pre-fabricated Surfaces for Assessment of Spatial Resolution and Proteomic Analysis of Tissue Samples using Imaging Mass Spectrometry. [Internet] [Doctoral dissertation]. Vanderbilt University; 2016. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/12500.

Council of Science Editors:

Zubair F. Pre-fabricated Surfaces for Assessment of Spatial Resolution and Proteomic Analysis of Tissue Samples using Imaging Mass Spectrometry. [Doctoral Dissertation]. Vanderbilt University; 2016. Available from: http://hdl.handle.net/1803/12500

Vanderbilt University

14. Shae, Daniel. Design and Optimization of ‘Smart’ Nanoparticles for Targeting of the STING Pathway with Applications in Cancer Immunotherapy.

Degree: PhD, Chemical Engineering, 2019, Vanderbilt University

URL: http://hdl.handle.net/1803/10674

► I detail the rational design and optimization of STING-NPs: a nanoparticle delivery platform that stimulates innate immunity and T cell activation through targeted activation of… (more)

Subjects/Keywords: Cancer Immunotherapy

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APA (6^th Edition):

Shae, D. (2019). Design and Optimization of ‘Smart’ Nanoparticles for Targeting of the STING Pathway with Applications in Cancer Immunotherapy. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/10674

Chicago Manual of Style (16^th Edition):

Shae, Daniel. “Design and Optimization of ‘Smart’ Nanoparticles for Targeting of the STING Pathway with Applications in Cancer Immunotherapy.” 2019. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/10674.

MLA Handbook (7^th Edition):

Shae, Daniel. “Design and Optimization of ‘Smart’ Nanoparticles for Targeting of the STING Pathway with Applications in Cancer Immunotherapy.” 2019. Web. 04 Mar 2021.

Vancouver:

Shae D. Design and Optimization of ‘Smart’ Nanoparticles for Targeting of the STING Pathway with Applications in Cancer Immunotherapy. [Internet] [Doctoral dissertation]. Vanderbilt University; 2019. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/10674.

Council of Science Editors:

Shae D. Design and Optimization of ‘Smart’ Nanoparticles for Targeting of the STING Pathway with Applications in Cancer Immunotherapy. [Doctoral Dissertation]. Vanderbilt University; 2019. Available from: http://hdl.handle.net/1803/10674

Vanderbilt University

15. Lawrie, Jenifer Lynn. In situ DNA synthesis in porous silicon for biosensing applications.

Degree: PhD, Interdisciplinary Materials Science, 2012, Vanderbilt University

URL: http://hdl.handle.net/1803/14187

► A bottom up approach to functionalizing high quality porous silicon optical structures with nucleic acid bioreceptors is presented in this dissertation. The solid-phase synthesis method… (more)

▼ A bottom up approach to functionalizing high quality porous silicon optical structures with nucleic acid bioreceptors is presented in this dissertation. The solid-phase synthesis method using phosphoramidite protected nucleic acids is applied for the first time in porous silicon waveguides to achieve DNA attachment within the pores. Biomolecule attachment is monitored by coupling light into the waveguide to probe changes in the effective refractive index of the optical structure. We show herein that the in situ DNA synthesis method achieves a higher surface coverage with bioreceptors than the traditional infiltration of pre-synthesized DNA strands into mesoporous silicon structures. With the in situ approach, DNA conformation, flexibility, and length play little role in DNA bioreceptor density within the substrate. The increased sensitivity resulting from in situ preparation of DNA functionalized porous silicon waveguide sensors has been demonstrated for 8-, 16-, and 24mer DNA oligo receptors and complementary nucleic acid targets, with the lowest detection limits in the nanomolar range. Functionalization of the porous silicon with a two-component silane monolayer, only one component of which is active for in situ DNA synthesis, allows for precise control of the synthesized DNA surface density. Tuning of the DNA density in the pores enables improved biosensor sensitivity by maximizing the number of bioreceptors that can capture target molecules without being impeded by steric crowding. Using synthesized DNA oligos in porous silicon as aptamers, highly selective detection of small molecule targets other than complementary DNA molecules is possible. This work demonstrates for the first time the optical measurement of DNA aptamer-based capture of small molecules in a porous silicon waveguide. Selective detection of the small molecules adenosine and ochratoxin A is described, providing evidence that DNA aptamers retain their functionality within the mesoporous substrate. This first demonstration of DNA aptamer-based sensing within porous silicon may be expanded to other small molecule targets of interest, combining the high selectivity of aptamer detection schemes with the sensitivity and filtering capabilities afforded by porous silicon waveguide sensors. Advisors/Committee Members: Richard F. Haglund, Jr (committee member), Paul E. Laibinis (committee member), Deyu Li (committee member), Michael P. Stone (committee member), Sharon M. Weiss (Committee Chair).

Subjects/Keywords: porous silicon; biosensing

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APA (6^th Edition):

Lawrie, J. L. (2012). In situ DNA synthesis in porous silicon for biosensing applications. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/14187

Chicago Manual of Style (16^th Edition):

Lawrie, Jenifer Lynn. “In situ DNA synthesis in porous silicon for biosensing applications.” 2012. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/14187.

MLA Handbook (7^th Edition):

Lawrie, Jenifer Lynn. “In situ DNA synthesis in porous silicon for biosensing applications.” 2012. Web. 04 Mar 2021.

Vancouver:

Lawrie JL. In situ DNA synthesis in porous silicon for biosensing applications. [Internet] [Doctoral dissertation]. Vanderbilt University; 2012. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/14187.

Council of Science Editors:

Lawrie JL. In situ DNA synthesis in porous silicon for biosensing applications. [Doctoral Dissertation]. Vanderbilt University; 2012. Available from: http://hdl.handle.net/1803/14187

Vanderbilt University

16. Xu, Zhou. Engineered microarrayed surfaces for the detection of biomolecules.

Degree: PhD, Chemical Engineering, 2011, Vanderbilt University

URL: http://hdl.handle.net/1803/11613

► DNA microarrays have become an increasingly important tool for genomic investigations. This work is directed toward establishing methods and surface architectures that allow the monitoring… (more)

▼ DNA microarrays have become an increasingly important tool for genomic investigations. This work is directed toward establishing methods and surface architectures that allow the monitoring of DNA hybridization and dehybridization at microarrayed surfaces in real time. For this purpose, a method for generating a surface architecture that allows end-immobilization of DNA probes with high sequence fidelity is provided. This method combines the advantages of solid-phase oligonucleotide synthesis chemistry and conventional microarray spotting for generating end-immobilized oligonucleotide structures at surfaces. Total internal reflection fluorescence (TIRF) imaging provided in situ measurements of the hybridization kinetics between target DNA molecules and surface oligonucleotides on a homogeneous surface. A transport limited reaction model that included the effects of diffusion and solution depletion yielded estimates of surface hybridization rate constants, equilibrium constants, and the surface probe densities. Non-equilibrium desorption melting curves for DNA probe-target duplexes on both homogeneous and patterned surfaces were obtained in situ by TIRF. Redhead theory was used to simulate the melting curves. Single base pair mismatch was discerned from the melting curves. Imaging mass spectrometry (IMS) has emerged as a powerful technology for examining the relative abundance and spatial localization of biomolecules in a thin tissue section. Current methods for IMS are time-consuming and require expensive equipment for sample preparation. This work employs pre-coated surfaces as a way to address these issues. Such surfaces were patterned by microcontact printing to form 100~200 µm hydrophilic spots surrounded by a continuous hydrophobic surface. Matrix crystals were regioselectively deposited onto the hydrophilic areas, forming a matrix crystal microarray. Tissue samples were placed directly onto the patterned matrix surfaces and then analyzed by IMS. This approach decreases sample preparation time from a few hours to tens of minutes, avoids the need for expensive spotters, and allows high-throughput imaging mass spectrometry at high resolution for tissue sample analysis. Advisors/Committee Members: Kenneth A. Debelak (committee member), Scott A. Guelcher (committee member), G. Kane Jennings (committee member), Sharon M. Weiss (committee member), Paul E. Laibinis (Committee Chair).

Subjects/Keywords: total internal reflection fluorescence; DNA melting; DNA hybridization; DNA microarray; microarray; imaging mass spectrometry

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APA (6^th Edition):

Xu, Z. (2011). Engineered microarrayed surfaces for the detection of biomolecules. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/11613

Chicago Manual of Style (16^th Edition):

Xu, Zhou. “Engineered microarrayed surfaces for the detection of biomolecules.” 2011. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/11613.

MLA Handbook (7^th Edition):

Xu, Zhou. “Engineered microarrayed surfaces for the detection of biomolecules.” 2011. Web. 04 Mar 2021.

Vancouver:

Xu Z. Engineered microarrayed surfaces for the detection of biomolecules. [Internet] [Doctoral dissertation]. Vanderbilt University; 2011. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/11613.

Council of Science Editors:

Xu Z. Engineered microarrayed surfaces for the detection of biomolecules. [Doctoral Dissertation]. Vanderbilt University; 2011. Available from: http://hdl.handle.net/1803/11613

Vanderbilt University

17. Tuberquia, Juan Carlos. Surface-initiated polymethylenation to grow superhydrophobic barrier films.

Degree: PhD, Chemical Engineering, 2011, Vanderbilt University

URL: http://hdl.handle.net/1803/12671

► The modification of surface properties has become a vital focus in materials research and is fueled by the interesting ways of tailoring composition, modifying architecture,… (more)

▼ The modification of surface properties has become a vital focus in materials research and is fueled by the interesting ways of tailoring composition, modifying architecture, and optimizing surface characteristics to impact a target application. This dissertation focuses on new approaches for the preparation and characterization of superhydrophobic (SH) surfaces. Here, we show that ultrathin films of the world’s simplest and most common polymer, polymethylene (PM) (or the chemically equivalent polyethylene), exhibit dramatically large resistances against the penetration of aqueous ions if their topology is sufficiently rough on both micro- and nano-scales to merit superhydrophobic behavior. To achieve these rough, yet thin, PM films, we have reported a new surface-initiated polymerization strategy in which immobilized borane moieties serve as active centers for the reaction with diazomethane to grow PM chains one methylene group at a time from a variety of substrates. We have explored the effect of superhydrophobicity on the dielectric properties of the film based on impedance measurements and the rationalization of such measurements using the Helmholtz theory. We have established that SH films exhibit positive deviations from the inverse capacitance predicted by the Helmholtz theory, and we have modeled the effect of the entrapped air at the PM/solution interface of SH films relative to smooth and non-superhydrophobic (NSH) films using a composite factor. Experimental results have demonstrated the remarkable sensitivity of impedance-based methods to assess the superhydrophobicity in underwater conditions. To take advantage of this potential, we have developed a strategy to identify the Cassie and the Wenzel states for underwater surfaces using impedance measurements. We have established the principles and theoretical concepts of the technique and applied it to a situation in which we explore how SH surfaces recover their initial Cassie state after transitioning into the Wenzel state and drying the liquid present in the grooves. Finally, we have discussed the extension of the SIPM approach to virtually any substrate that has incorporated olefin groups; more specifically, we have explored a strategy to grow SH films from liquid polymer substrates to introduce the concept of a SH veneer atop a NSH surface. Advisors/Committee Members: Paul E. Laibinis (committee member), Eugene LeBoeuf (committee member), M. Douglas LeVan (committee member), Peter N. Pintauro (committee member), G. Kane Jennings (Committee Chair).

Subjects/Keywords: polyethylene; EIS; impedance; superhydrophobic; surface initiated polymerization; borane; Helmholtz theory; Cassie; Wenzel

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APA (6^th Edition):

Tuberquia, J. C. (2011). Surface-initiated polymethylenation to grow superhydrophobic barrier films. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/12671

Chicago Manual of Style (16^th Edition):

Tuberquia, Juan Carlos. “Surface-initiated polymethylenation to grow superhydrophobic barrier films.” 2011. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/12671.

MLA Handbook (7^th Edition):

Tuberquia, Juan Carlos. “Surface-initiated polymethylenation to grow superhydrophobic barrier films.” 2011. Web. 04 Mar 2021.

Vancouver:

Tuberquia JC. Surface-initiated polymethylenation to grow superhydrophobic barrier films. [Internet] [Doctoral dissertation]. Vanderbilt University; 2011. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/12671.

Council of Science Editors:

Tuberquia JC. Surface-initiated polymethylenation to grow superhydrophobic barrier films. [Doctoral Dissertation]. Vanderbilt University; 2011. Available from: http://hdl.handle.net/1803/12671

Vanderbilt University

18. Spears, Robin Jay. Superhydrophobic Polymethylene Films.

Degree: MS, Chemical Engineering, 2009, Vanderbilt University

URL: http://hdl.handle.net/1803/15215

► SUPERHYDROPHOBIC POLYMETHYLENE FILMS The preparation, characterization, and stability of polymethylene films grown from metallic surfaces is presented in this thesis. Polymethylene films were produced in… (more)

Subjects/Keywords: Superhydrophobicity

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APA (6^th Edition):

Spears, R. J. (2009). Superhydrophobic Polymethylene Films. (Thesis). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/15215

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):

Spears, Robin Jay. “Superhydrophobic Polymethylene Films.” 2009. Thesis, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/15215.

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

MLA Handbook (7^th Edition):

Spears, Robin Jay. “Superhydrophobic Polymethylene Films.” 2009. Web. 04 Mar 2021.

Vancouver:

Spears RJ. Superhydrophobic Polymethylene Films. [Internet] [Thesis]. Vanderbilt University; 2009. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/15215.

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

Council of Science Editors:

Spears RJ. Superhydrophobic Polymethylene Films. [Thesis]. Vanderbilt University; 2009. Available from: http://hdl.handle.net/1803/15215

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

Vanderbilt University

19. Berron, Bradley Joseph. Engineering of novel fuel cell cathode interfaces with surface-initiated ionomer films based on modified polynorbornene.

Degree: PhD, Chemical Engineering, 2008, Vanderbilt University

URL: http://hdl.handle.net/1803/10606

► In this dissertation we describe a strategy to molecularly optimize the cathode side of a proton exchange membrane fuel cell. This new cathode consists of… (more)

▼ In this dissertation we describe a strategy to molecularly optimize the cathode side of a proton exchange membrane fuel cell. This new cathode consists of a porous gold membrane with pores that function as gas diffusion conduits while supporting a catalyst layer and ionomer. The ionomer chains are grown from the surface of the pore walls and are designed to encapsulate the catalyst particles to provide a well-defined three-phase boundary for gas, proton, and electron transfer. A new class of ionomer prepared by the surface-initiated ring-opening metathesis polymerization of a functionalized norbornene and subsequent sulfonation with acetyl sulfate is evaluated. These ionomers are grown rapidly and conformally over any surface geometry with nanometer-level control over thickness. The effectiveness of a high-utilization catalyst attachment method is demonstrated through electrochemical monitoring of the oxygen reduction reaction. A platinum submonolayer deposited onto the gold substrate is catalytically active in the oxygen reduction reaction, and the activity of the catalyst is preserved during the deposition of the sulfonated polynorbornene ionomer overlayer. Nanoporous gold substrates are prepared through the exposure of a ~100 nm alloy sheet of gold and silver to nitric acid followed by binding onto a gold substrate. The nanoporous gold substrate demonstrates a 10x improvement in electrochemically active surface area available and is compatible with the deposition of a platinum monolayer. The incorporation of the sulfonated polynorbornene into the platinum-coated support decreases the oxygen reduction capacity of the electrode, likely due to poor oxygen permeability in the ionomer as well as reduced volume for oxygen transport within the nanoporous support. Advisors/Committee Members: Charles Lukehart (committee member), Kenneth A. Debelak (committee member), Scott A. Guelcher (committee member), Paul E. Laibinis (committee member), G. Kane Jennings (Committee Chair).

Subjects/Keywords: Fuel cells – Design and construction; electrode; ionomer; surface initiated; Cathodes – Design and construction; lonomers

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APA (6^th Edition):

Berron, B. J. (2008). Engineering of novel fuel cell cathode interfaces with surface-initiated ionomer films based on modified polynorbornene. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/10606

Chicago Manual of Style (16^th Edition):

Berron, Bradley Joseph. “Engineering of novel fuel cell cathode interfaces with surface-initiated ionomer films based on modified polynorbornene.” 2008. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/10606.

MLA Handbook (7^th Edition):

Berron, Bradley Joseph. “Engineering of novel fuel cell cathode interfaces with surface-initiated ionomer films based on modified polynorbornene.” 2008. Web. 04 Mar 2021.

Vancouver:

Berron BJ. Engineering of novel fuel cell cathode interfaces with surface-initiated ionomer films based on modified polynorbornene. [Internet] [Doctoral dissertation]. Vanderbilt University; 2008. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/10606.

Council of Science Editors:

Berron BJ. Engineering of novel fuel cell cathode interfaces with surface-initiated ionomer films based on modified polynorbornene. [Doctoral Dissertation]. Vanderbilt University; 2008. Available from: http://hdl.handle.net/1803/10606

Vanderbilt University

20. Faulkner, Christopher James. Investigation of electrochemical interfaces for the development of novel electrodes for biomimetic energy conversion and hydrogen fuel cells.

Degree: PhD, Chemical Engineering, 2010, Vanderbilt University

URL: http://hdl.handle.net/1803/10542

► Heightened awareness in global warming and an increasing demand in energy consumption have generated a surging interest in creating sustainable alternative energy sources. One of… (more)

▼ Heightened awareness in global warming and an increasing demand in energy consumption have generated a surging interest in creating sustainable alternative energy sources. One of the major challenges of incorporating existing technologies into societal infrastructure is the cost of alternative energies, such as solar and fuel cells. In order to reduce the cost of these technologies, either existing technologies need to be made more efficient or a fundamental rethink of current designs is necessary. An essential component of these energy conversion technologies is the interfacial charge transfer from the cells to an external circuit. The research presented in this thesis focuses on the engineering of electrode interfaces for biomimetic energy conversion and the “triple-interface” of the cathode in proton exchange membrane fuel cells (PEM-FCs). The first part of this thesis describes the incorporation of Photosystem I, a 500 kDa protein macromolecule involved in the light reactions of photosynthesis, onto electrodes that enable the conversion of photons into chemical and ultimately electrical energy. Self-assembled monolayers (SAMs) were used to directly wire the protein complexes to gold electrode surfaces in a simple, fast manner. The vacuum-assisted deposition technique developed to assemble PSI enabled the formation of active PSI films ~80 times faster than previous methods. Additionally, this deposition technique allows for the formation of thick, ~ 1 micron, PSI films that produce an order of magnitude more photocurrent than monolayer films. The second part of this thesis describes the synthesis and surface-initiated polymerization of a new class of partially fluorinated polymers for use in PEM-FCs. The 5-(perfluoro-n-alkyl)norbornenes (where n = 4, 6, 8, 10) were synthesized using a Diels-Alder reaction between a perfluorinated alkene and cyclopentadiene. Utilizing surface-initiated ring-opening metathesis (SI-ROMP) and appropriate surface-bound initiators, polymer films were grown from 2-D planar gold, 3-D nanoporous gold leaf, and 3-D carbon fiber electrodes. Upon sulfonation, the barrier properties of these films change dramatically. The transport properties of aqueous species through these systems were measured using electrochemical impedance spectroscopy and are discussed. Advisors/Committee Members: Paul E Laibinis (committee member), Scott A. Guelcher (committee member), David E. Cliffel (committee member), Bridget R. Rogers (committee member), G. Kane Jennings (Committee Chair).

Subjects/Keywords: photosynthesis; surface modification; surface characterization; fluoropolymer; protein adsorption

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APA (6^th Edition):

Faulkner, C. J. (2010). Investigation of electrochemical interfaces for the development of novel electrodes for biomimetic energy conversion and hydrogen fuel cells. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/10542

Chicago Manual of Style (16^th Edition):

Faulkner, Christopher James. “Investigation of electrochemical interfaces for the development of novel electrodes for biomimetic energy conversion and hydrogen fuel cells.” 2010. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/10542.

MLA Handbook (7^th Edition):

Faulkner, Christopher James. “Investigation of electrochemical interfaces for the development of novel electrodes for biomimetic energy conversion and hydrogen fuel cells.” 2010. Web. 04 Mar 2021.

Vancouver:

Faulkner CJ. Investigation of electrochemical interfaces for the development of novel electrodes for biomimetic energy conversion and hydrogen fuel cells. [Internet] [Doctoral dissertation]. Vanderbilt University; 2010. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/10542.

Council of Science Editors:

Faulkner CJ. Investigation of electrochemical interfaces for the development of novel electrodes for biomimetic energy conversion and hydrogen fuel cells. [Doctoral Dissertation]. Vanderbilt University; 2010. Available from: http://hdl.handle.net/1803/10542

Vanderbilt University

21. Li, Bing. Biodegradable Polyurethane Scaffolds and Delivery Systems for Regeneration of Bone Tissue.

Degree: PhD, Chemical Engineering, 2010, Vanderbilt University

URL: http://hdl.handle.net/1803/12286

► Infection is a common complication in open fractures that compromises bone healing. Currently, the clinical standard care for treating contaminated open fractures comprises a staged… (more)

▼ Infection is a common complication in open fractures that compromises bone healing. Currently, the clinical standard care for treating contaminated open fractures comprises a staged approach, wherein the wound is first treated with antibiotic-laden PMMA beads to control the infection followed by bone grafting. However, the non-biodegradable PMMA must be removed during an extra surgical step. While complications may also arise from the wound healing process, it is critical to control infection in the graft as well. In this Ph.D. dissertation, I aimed to combine both steps in the traditional treatment to allow both infection control and wound healing to occur simultaneously, which has been achieved by delivering both vancomycin (an antibiotic) and bone morphogenetic protein (rhBMP-2, a morphogen growth factor) from biodegradable porous polyurethane composite scaffolds. Porous polyurethane scaffolds were synthesized from a two-component reaction between polyester triol and triisocyanate with desired mechanical properties and degradation kinetics. The drugs were incorporated within the scaffolds as well, and the release rates were tuned to the biological requirements of the clinical indication. Through the PLGA microencapsulation approach to control the release of rhBMP-2, we found that both burst release as well as sustained release is desired to optimize bone regeneration in rat femoral defects. The effective therapeutic concentration release of vancomycin was sustained for up to at least 8 weeks by transferring commercially available vancomycin hydrochloride to vancomycin free base that has significantly decreased solubility, which translated to better infection control in an infected rat femoral segmental defect. The polymer composites containing both rhBMP-2 and vancomycin free base were then tested in an infected rat femoral segmental defect. The prolonged release of antibiotic controls infection, allowing bone healing process to occur which was accelerated by the sustained release of rhBMP-2. The strategy of protecting the graft from infection during wound healing eliminates an extra surgical removal step in current clinical standard care, and presents a potentially significant innovation in clinical treatment of infected bone wounds. Advisors/Committee Members: Kenneth A. Debelak (committee member), Jeffrey M. Davidson (committee member), Paul E. Laibinis (committee member), Jamey D. Young (committee member), Scott A. Guelcher (Committee Chair).

Subjects/Keywords: Polyurethane; Animal study; Drug delivery; Antibiotic; Infection control; Tissue engineering; Growth factors; Biomaterials; New bone formation

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APA (6^th Edition):

Li, B. (2010). Biodegradable Polyurethane Scaffolds and Delivery Systems for Regeneration of Bone Tissue. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/12286

Chicago Manual of Style (16^th Edition):

Li, Bing. “Biodegradable Polyurethane Scaffolds and Delivery Systems for Regeneration of Bone Tissue.” 2010. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/12286.

MLA Handbook (7^th Edition):

Li, Bing. “Biodegradable Polyurethane Scaffolds and Delivery Systems for Regeneration of Bone Tissue.” 2010. Web. 04 Mar 2021.

Vancouver:

Li B. Biodegradable Polyurethane Scaffolds and Delivery Systems for Regeneration of Bone Tissue. [Internet] [Doctoral dissertation]. Vanderbilt University; 2010. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/12286.

Council of Science Editors:

Li B. Biodegradable Polyurethane Scaffolds and Delivery Systems for Regeneration of Bone Tissue. [Doctoral Dissertation]. Vanderbilt University; 2010. Available from: http://hdl.handle.net/1803/12286

Vanderbilt University

22. Hafeman, Andrea Elise. Polyurethane scaffold with delivery of biologically active small molecules for tissue regeneration.

Degree: PhD, Chemical Engineering, 2010, Vanderbilt University

URL: http://hdl.handle.net/1803/11703

► Limited availability of autograft tissue for bone and skin wound healing has established the demand for improved synthetic biomaterials. Biodegradable polyurethane (PUR) scaffolds exhibit favorable… (more)

▼ Limited availability of autograft tissue for bone and skin wound healing has established the demand for improved synthetic biomaterials. Biodegradable polyurethane (PUR) scaffolds exhibit favorable properties for wound healing applications, as they support cellular proliferation and new tissue formation both in vitro and in vivo. This work describes the design and development of PUR scaffolds with polyester triols and aliphatic triisocyanates. The scaffolds, with up to 93% porosity, were evaluated based on physical, thermal, mechanical, and biological properties; these properties could be adjusted by variations in PUR scaffold composition. Furthermore, the scaffolds were formulated for injectable application, which allows for customizable and minimally invasive procedures. PUR scaffolds degrade by hydrolysis in vitro, but faster degradation in vivo implicates cell-mediated degradation, specifically by macrophages along the material surfaces. Indeed, PUR degradation was accelerated in vitro when the scaffolds were incubated in enzymatic or oxidative media. In particular, reactive oxygen intermediates had a significant effect on degradation, presumably causing chain scission in both the hard and soft segments of the PUR. Biologically active molecules, such as antibiotics, small molecule drugs, and growth factors, were incorporated into the foams during synthesis for local, controlled release to enhance wound repair. Local antibiotic delivery could help in healing infected wounds, especially bone fractures, as the scaffold and antibiotic delivery system could be administered in one procedure. This would preclude the need to first implant antibiotic-loaded cement beads, followed by additional surgeries to remove the beads and implant a bone graft. Lovastatin is known to stimulate osteogenesis, and so it was also examined as a potential additive for local release. Scaffolds containing lovastatin enhanced new bone formation both in vitro and in vivo within the defect area. Due to their injectability, biocompatibility, tunable degradation, and potential for release of biologically active small molecules, these PUR scaffolds are potentially promising therapies for tissue engineering. Advisors/Committee Members: G. Kane Jennings (committee member), Jeffrey M. Davidson (committee member), M. Douglas LeVan (committee member), Paul E. Laibinis (committee member), Scott A. Guelcher (Committee Chair).

Subjects/Keywords: skin wound healing; bone fracture repair; tissue engineering; mechanical properties; controlled release; elastomeric; biodegradable; porous; injectable; lovastatin; antibiotic

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

APA (6^th Edition):

Hafeman, A. E. (2010). Polyurethane scaffold with delivery of biologically active small molecules for tissue regeneration. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/11703

Chicago Manual of Style (16^th Edition):

Hafeman, Andrea Elise. “Polyurethane scaffold with delivery of biologically active small molecules for tissue regeneration.” 2010. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/11703.

MLA Handbook (7^th Edition):

Hafeman, Andrea Elise. “Polyurethane scaffold with delivery of biologically active small molecules for tissue regeneration.” 2010. Web. 04 Mar 2021.

Vancouver:

Hafeman AE. Polyurethane scaffold with delivery of biologically active small molecules for tissue regeneration. [Internet] [Doctoral dissertation]. Vanderbilt University; 2010. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/11703.

Council of Science Editors:

Hafeman AE. Polyurethane scaffold with delivery of biologically active small molecules for tissue regeneration. [Doctoral Dissertation]. Vanderbilt University; 2010. Available from: http://hdl.handle.net/1803/11703

Vanderbilt University

23. Ciesielski, Peter Nolan. Photosystem I – Based Systems for Photoelectrochemical Energy Conversion.

Degree: PhD, Interdisciplinary Materials Science, 2010, Vanderbilt University

URL: http://hdl.handle.net/1803/13923

► This dissertation investigates the incorporation of Photosystem I (PSI), a supramolecular protein complex that participates in the light reactions of photosynthesis, into electrochemical systems intended… (more)

Subjects/Keywords: bionanotechnology; electrochemistry; energy conversion

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

APA (6^th Edition):

Ciesielski, P. N. (2010). Photosystem I – Based Systems for Photoelectrochemical Energy Conversion. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/13923

Chicago Manual of Style (16^th Edition):

Ciesielski, Peter Nolan. “Photosystem I – Based Systems for Photoelectrochemical Energy Conversion.” 2010. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/13923.

MLA Handbook (7^th Edition):

Ciesielski, Peter Nolan. “Photosystem I – Based Systems for Photoelectrochemical Energy Conversion.” 2010. Web. 04 Mar 2021.

Vancouver:

Ciesielski PN. Photosystem I – Based Systems for Photoelectrochemical Energy Conversion. [Internet] [Doctoral dissertation]. Vanderbilt University; 2010. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/13923.

Council of Science Editors:

Ciesielski PN. Photosystem I – Based Systems for Photoelectrochemical Energy Conversion. [Doctoral Dissertation]. Vanderbilt University; 2010. Available from: http://hdl.handle.net/1803/13923

Vanderbilt University

24. Stowers, Christopher Clay. Next generation quantitative measurements to validate a model for Saccharomyces cerevisiae.

Degree: PhD, Chemical Engineering, 2008, Vanderbilt University

URL: http://hdl.handle.net/1803/12590

► Dissertation under the direction of Professor Kenneth A. Debelak The study of dynamical biological systems is currently obstructed by the lack of quantitative methods available… (more)

▼ Dissertation under the direction of Professor Kenneth A. Debelak The study of dynamical biological systems is currently obstructed by the lack of quantitative methods available for biophysical measurement. The focus of this work is to further develop these methods so the dynamics of genetic circuitry can be studied at the same level of sophistication at which mathematical models have been formulated. The study of biological dynamics provides an interesting research opportunity because these dynamics control the emergent behavior of living organisms and result in the observed robustness of life. The specific system that provides the focus for this work is an ostensibly simple stress response circuit in baker’s yeast, Saccharomyces cerevisiae, which regulates the organism’s genetic response to nitrogen limitation called Nitrogen Catabolite Repression (NCR). The work presented in this dissertation encompasses many of the aspects of gene expression analysis including cell disruption, cell cycle synchrony, and the amplification and quantitation of genetic signals through Polymerase Chain Reaction (PCR). In each case, a combination of experimental results, engineering intuition, and mathematical analysis is used to further develop current techniques and understanding. Mathematical models are developed for cell disruption, cell cycle synchrony, and endpoint PCR. These models are used to advance the level of quantitation available to each process. When applied, these models provide novel insight to persistent biological problems. For example, cell disruption was found to be a cell cycle dependent process, volume filtration was developed as a theoretical mechanism for extending cell cycle synchrony, and autonomous oscillations within continuous yeast cultures were shown to be a result of pseudo cell cycle synchrony. Advisors/Committee Members: Robert D. Tanner (committee member), Paul E. Laibinis (committee member), Rick R. Haselton (committee member), Todd D. Giorgio (committee member), Erik M. Boczko (committee member), Kenneth A. Debelak (Committee Chair).

Subjects/Keywords: Saccharomyces cerevisiae – Effect of stress on – Mathematical models; Saccharomyces cerevisiae – Genetics – Mathematical models; cell disruption; bioprocessing; nitrogen catabolite repression; Leslie model; cell cycle; polymerase chain reaction; autonomous oscillations; Gene expression – Measurement; Biological systems – Mathematical models

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APA (6^th Edition):

Stowers, C. C. (2008). Next generation quantitative measurements to validate a model for Saccharomyces cerevisiae. (Doctoral Dissertation). Vanderbilt University. Retrieved from http://hdl.handle.net/1803/12590

Chicago Manual of Style (16^th Edition):

Stowers, Christopher Clay. “Next generation quantitative measurements to validate a model for Saccharomyces cerevisiae.” 2008. Doctoral Dissertation, Vanderbilt University. Accessed March 04, 2021. http://hdl.handle.net/1803/12590.

MLA Handbook (7^th Edition):

Stowers, Christopher Clay. “Next generation quantitative measurements to validate a model for Saccharomyces cerevisiae.” 2008. Web. 04 Mar 2021.

Vancouver:

Stowers CC. Next generation quantitative measurements to validate a model for Saccharomyces cerevisiae. [Internet] [Doctoral dissertation]. Vanderbilt University; 2008. [cited 2021 Mar 04]. Available from: http://hdl.handle.net/1803/12590.

Council of Science Editors:

Stowers CC. Next generation quantitative measurements to validate a model for Saccharomyces cerevisiae. [Doctoral Dissertation]. Vanderbilt University; 2008. Available from: http://hdl.handle.net/1803/12590

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