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North-West University
1.
Helena (nee Slabbert), Chrizaan.
Formulation, characterization and cellular toxicity of lipid based drug delivery systems for mefloquin / Chrizaan Helena (nee Slabbert)
.
Degree: 2011, North-West University
URL: http://hdl.handle.net/10394/8433
► Malaria affects millions of people annually especially in third world countries. Increase in resistance and limited research being conducted adds to the global burden of…
(more)
▼ Malaria affects millions of people annually especially in third world countries. Increase in resistance and limited research being conducted adds to the global burden of malaria. Mefloquine, known for unwanted adverse reactions and neurotoxicity, is highly lipophilic and is still used as treatment and prophylaxis. Lipid drug delivery systems are commonly used to increase solubility and efficacy and decrease toxicity. The most generally used lipid drug delivery system is liposomes. The lipid bilayer structure varying in size from 25 nm to 100 μm can entrap both hydrophilic and lipophilic compounds. Similar in structure and size to liposomes, Pheroid™ technology consist of natural fatty acids and is also able to entrap lipophilic and hydrophilic compounds. The aim of this study was to formulate liposomes and Pheroid™ vesicles loaded with mefloquine and evaluate the physiochemical characteristic of the formulations followed by efficacy and toxicity studies. Pheroid™ vesicles and liposomes with and without mefloquine were evaluated in size, morphology, pH and entrapment efficacy during three month accelerated stability testing. Optimization of size determination by flow cytometry lead to accurate determination of size for both Pheroid™ vesicles and liposomes. During the three months stability testing, Pheroid™ vesicles showed a small change in size from 3.07 ± 0.01 μm to approximately 3 μm for all three temperatures. Confocal laser scanning microscopic evaluation of the liposomes showed structures uniform in spherical shape and size. No difference in size or structure between the Pheroid™ vesicles with and without mefloquine were obtained. Significant increase (p=0.027) in size from 6.46 ± 0.01 μm to above 10 μm was observed for liposomes at all the temperatures. Clearly formed lipid bilayer structures were observed on micrographs. With the addition of mefloquine to the liposome formulation, a decrease in the amount of bilayer structures and an increase in oil droplets were found. Entrapment efficacy was determined by firstly separating the entrapped drug from the unentrapped drug utilizing a Sephadex®G50 mini column. This was followed by spectrophotometric evaluation by UV-spectrophotometry at 283 nm. Initial entrapment efficacy of both Pheroid™ vesicles and liposomes was above 60%. An increase in entrapment efficacy was observed for Pheroid™ vesicles. The addition of mefloquine to already formulated Pheroid™ vesicles illustrated entrapment efficacy of 60.14 ± 5.59% after 14 days. Formulations loaded with mefloquine resulted in lower pH values as well as a decrease in pH over time. Optimization of efficacy studies utilizing propidium iodide was necessary due to the similarity in size and shape of the drug delivery systems to erythrocytes. A gating strategy was successfully implemented for the determination of the percentage parasitemia. Efficacy testing of mefloquine loaded in Pheroid™ vesicles and liposomes showed a 186% and 207% decrease in parasitemia levels compared to the control of mefloquine. Toxicity studies…
Subjects/Keywords: Pheroid™ Technology;
Liposomes;
Mefloquine;
Efficacy;
Neurotoxicity;
Haemolysis;
ROS analysis;
Pheroid™ tegnologie;
Liposome;
Meflokien;
Effektiwiteit;
Neurotoksisiteit;
Hemolise;
RSS analise
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Helena (nee Slabbert), C. (2011). Formulation, characterization and cellular toxicity of lipid based drug delivery systems for mefloquin / Chrizaan Helena (nee Slabbert)
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/8433
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Helena (nee Slabbert), Chrizaan. “Formulation, characterization and cellular toxicity of lipid based drug delivery systems for mefloquin / Chrizaan Helena (nee Slabbert)
.” 2011. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/8433.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Helena (nee Slabbert), Chrizaan. “Formulation, characterization and cellular toxicity of lipid based drug delivery systems for mefloquin / Chrizaan Helena (nee Slabbert)
.” 2011. Web. 16 Apr 2021.
Vancouver:
Helena (nee Slabbert) C. Formulation, characterization and cellular toxicity of lipid based drug delivery systems for mefloquin / Chrizaan Helena (nee Slabbert)
. [Internet] [Thesis]. North-West University; 2011. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/8433.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Helena (nee Slabbert) C. Formulation, characterization and cellular toxicity of lipid based drug delivery systems for mefloquin / Chrizaan Helena (nee Slabbert)
. [Thesis]. North-West University; 2011. Available from: http://hdl.handle.net/10394/8433
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
2.
Kruger, Lorraine.
Pheroid technology for the transdermal delivery of lidocaine and prilocaine / Lorraine Kruger
.
Degree: 2008, North-West University
URL: http://hdl.handle.net/10394/4028
► Local anaesthetics have been implemented extensively in the case of a variety of painful superficial procedures, venipuncture, skin graft harvesting, anal or genital pruritus, poison…
(more)
▼ Local anaesthetics have been implemented extensively in the case of a variety of painful
superficial procedures, venipuncture, skin graft harvesting, anal or genital pruritus, poison ivy
rashes, postherpetic neuralgia and several other dermatoses. The dilemma with
commercially available local acting anaesthetics is that it may take well up to an hour to
produce an anaesthetic effect. Anaesthetics have to traverse the highly efficient barrier, the
stratum corneum, in order to reach the intended target site which is the free nerve endings
located in the dermis.
The objective of this study was to compare the transdermal delivery of an eutectic
combination of two ionisable amide types of local anaesthetics, lidocaine HCI and
prilocaine HCI, delivered with the novel Pheroid™ technology to that of a commercially
available product in order to establish whether the lag time could be significantly reduced.
Several techniques of promoting the penetration of these anaesthetics have previously been
employed, including occlusive dressing, entrapment in liposomes and miscelles,
iontophoretic delivery and so forth. The Pheroid™ delivery system is novel technology that
entails improved delivery of several active compounds. It is a submicron emulsion type
formulation that possesses the ability to be transformed in morphology and size, thereby
affording it tremendous flexibility. Since it primarily consists of unsaturated essential fatty
acids, it is not seen as foreign to the body but rather as a skin-friendly carrier.
Vertical Franz cell diffusion studies were performed over a 12 hour period using Caucasian female abdominal skin obtained, with the consent of the donor, from abdominoplastic surgery. Comparison was made between the commercial product EMLA® cream, the active local anaesthetics dissolved in phosphate buffered solution (PBS) and the active ingredients entrapped within Pheroid™ vesicles. Distinct entrapment could be ascertained visually by confocal laser scanning microscopy (CLSM). The amount of drug that traversed the epidermal membrane into the receptor phase was then assayed by high performance liquid chromatography (HPLC).
The results obtained with the Pheroid™ vesicles revealed a biphasic character with rapid permeation during the first two hours, followed by a plateau between 3 to 12 hours. The initial dramatic increase in percentage yield and flux indicates that the Pheroid™ carrier enhances the transdermal delivery of the actives in order to accelerate the onset of action.
Subjects/Keywords: Transdermal delivery;
Pheroid;
Lidocaine hydrochloride;
Prilocaine hydrochloride;
Local anaesthesia
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kruger, L. (2008). Pheroid technology for the transdermal delivery of lidocaine and prilocaine / Lorraine Kruger
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/4028
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kruger, Lorraine. “Pheroid technology for the transdermal delivery of lidocaine and prilocaine / Lorraine Kruger
.” 2008. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/4028.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kruger, Lorraine. “Pheroid technology for the transdermal delivery of lidocaine and prilocaine / Lorraine Kruger
.” 2008. Web. 16 Apr 2021.
Vancouver:
Kruger L. Pheroid technology for the transdermal delivery of lidocaine and prilocaine / Lorraine Kruger
. [Internet] [Thesis]. North-West University; 2008. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/4028.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kruger L. Pheroid technology for the transdermal delivery of lidocaine and prilocaine / Lorraine Kruger
. [Thesis]. North-West University; 2008. Available from: http://hdl.handle.net/10394/4028
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
3.
Chinembiri, Tawona Nyasha.
Optimised topical delivery of 5-fluorouracil
.
Degree: 2012, North-West University
URL: http://hdl.handle.net/10394/9000
► Skin cancer is the most widely diagnosed form of cancer and it is split in to non-melanoma skin cancer (NMSC) and cutaneous malignant melanoma (CMM).…
(more)
▼ Skin cancer is the most widely diagnosed form of cancer and it is split in to non-melanoma skin cancer (NMSC) and cutaneous malignant melanoma (CMM). Cutaneous melanoma has a high propensity for malignancy and it has the highest mortality rate of all skin cancers (de Gruijl, 1999:2004). The first line of treatment for most skin cancers is surgical excision but instances do arise in which surgery is not feasible due to the health of the patient or the location of the lesion. Therefore, viable alternatives are necessary in cases where surgery is not possible (Telfer et al., 2008:36). The skin is readily available for delivery of cytotoxic drugs to treat carcinomas and melanomas so the topical delivery of 5-fluorouracil was investigated in this study.
5-Fluorouracil is a pyrimidine anti-metabolite which interferes with deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) synthesis by inhibiting the nucleotide synthetic enzyme thymidylate synthase (TS) and by becoming misincorporated into RNA and DNA. Thymidylate is essential for replication as well as repair of DNA, in the event of TS inhibition thymidylate is not formed and “thymineless deaths” of cells occur (Chu & Sartorelli, 2009:935; Longley et al., 2003:330). This active pharmaceutical ingredient (API) causes death of atypical and rapidly dividing cells (Tsuji & Karasek, 1986:474). The intravenous and topical routes are approved for 5-fluorouracil and in the case of skin cancer the obvious choice would be topical application (Chu & Sartorelli, 2009:935). Topical application of 5-fluorouracil results in the occurrence of terrible side effects such as severe inflammation, stomatitis, photosensitivity and dermatitis. A reduction in side effects would reduce the stigma associated with topical 5-fluorouracil and in turn increase patient compliance.
Topical drug delivery entails the delivery of an API onto or into the various layers of the skin (Flynn & Weiner, 1993:33) in order to treat conditions on or within the skin. Topical application of APIs is non-invasive, painless and simple plus the target site is readily accessible for topical therapy, thus the API is delivered directly to the site of action (Naik et al., 2000:318). In the case of skin cancer, 5-fluorouracil should be able to reach the epidermis because NMSC originates from the keratinocytes (Marks & Hanson, 2010:305) and CMM from melanocytes (de Gruijl, 1999:2004) which are both found in the epidermis. The barrier function of the skin limits the penetration of molecules into the skin and the rate-limiting step is usually penetration into the stratum corneum (Foldvari, 2000:418).
The aim of this study was to investigate the diffusion of 5-fluorouracil from formulations into and through the skin. Two physico-chemical properties of 5-fluorouracil that influence skin permeation were determined (aqueous solubility and n-octanol-buffer partition coefficient (log D)). The Pheroid™ drug delivery system was used to enhance the delivery of 5-fluorouracil (Grobler et al., 2008:284). Pheroid™ is a novel…
Subjects/Keywords: Skin cancer;
5-fluorouracil;
Pheroid™;
A375 cells;
Cell culture
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Chinembiri, T. N. (2012). Optimised topical delivery of 5-fluorouracil
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/9000
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Chinembiri, Tawona Nyasha. “Optimised topical delivery of 5-fluorouracil
.” 2012. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/9000.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Chinembiri, Tawona Nyasha. “Optimised topical delivery of 5-fluorouracil
.” 2012. Web. 16 Apr 2021.
Vancouver:
Chinembiri TN. Optimised topical delivery of 5-fluorouracil
. [Internet] [Thesis]. North-West University; 2012. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/9000.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Chinembiri TN. Optimised topical delivery of 5-fluorouracil
. [Thesis]. North-West University; 2012. Available from: http://hdl.handle.net/10394/9000
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
4.
Kotzé, Jeanéne Celesté.
Nasal drug delivery of calcitonin with pheroid technology / Jeanéne Celesté Kotzé
.
Degree: 2005, North-West University
URL: http://hdl.handle.net/10394/888
► Advances in biotechnology and recombinant technologies have lead to the production of several classes of new drugs such as peptide and protein drugs. These compounds…
(more)
▼ Advances in biotechnology and recombinant technologies have lead to the
production of several classes of new drugs such as peptide and protein drugs.
These compounds are mostly indicated for chronic use but their inherent
characteristics such as size, polarity and stability prevent them from
incorporation in novel dosage forms. The bioavailability of nearly all peptide
drugs is very low due to poor absorption from the administration site. Several
challenges confront the pharmaceutical scientist in developing effective and
innovative dosage forms for these classes of drugs. A lot of attention has
been given to the nasal route of drug administration for delivery of peptide
drugs. The availability of several promising classes of absorption enhancers
and new drug delivery technologies has also prompt scientists to develop new
delivery systems for nasal administration of peptide drugs.
It has been shown in recent years that N-trimethyl chitosan chloride (TMC), a
quaternary derivative of chitosan, is effective in enhancing the absorption of
several peptide drugs, both in the peroral route and in the nasal route of drug
administration. Early indications are that new drug delivery technologies such
as Pheroid technology will also be able to enhance peptide drug absorption in
the nasal route. The aim of this study was to evaluate and compare the
absorption enhancing abilities of TMC and Pheroid technology in the nasal
delivery of calcitonin, a peptide hormone with low bioavailability.
Pheroid vesicles and Pheroid microsponges were prepared and characterized
for their morphology and size distribution. Calcitonin was entrapped into these
vesicles and microsponges and TMC and TMO solutions (0.5 % w/v),
containing calcitonin, was also prepared. These formulations were
administered nasally to rats in a volume of 100 μl/kg body-weight to obtain a
final concentration of 10 IU/kg body-weight of calcitonin. Plasma calcitonin
and calcium levels were determined over a period of 3 hours.
The results of this study clearly indicated that both Pheroid formulations and
the TMC formulation increase the nasal absorption of calcitonin with a
resulting decrease in plasma calcium levels, indicating an increased
absorption of calcitonin. The highest increase in calcitonin absorption was
obtained with the TMC formulation and this was explained by the difference in
the mechanism of action in enhancing peptide absorption between TMC and
Pheroid technology. It was concluded that Pheroid technology is also a potent
system to enhance peptide drug delivery and that the exact mechanism of
action should be investigated further.
Subjects/Keywords: Calcitonin;
Pheroid vesicles;
Pheroid microsponges;
N-trimethyl chitosan chloride (TMC);
Nasal drug delivery
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kotzé, J. C. (2005). Nasal drug delivery of calcitonin with pheroid technology / Jeanéne Celesté Kotzé
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/888
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kotzé, Jeanéne Celesté. “Nasal drug delivery of calcitonin with pheroid technology / Jeanéne Celesté Kotzé
.” 2005. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/888.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kotzé, Jeanéne Celesté. “Nasal drug delivery of calcitonin with pheroid technology / Jeanéne Celesté Kotzé
.” 2005. Web. 16 Apr 2021.
Vancouver:
Kotzé JC. Nasal drug delivery of calcitonin with pheroid technology / Jeanéne Celesté Kotzé
. [Internet] [Thesis]. North-West University; 2005. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/888.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kotzé JC. Nasal drug delivery of calcitonin with pheroid technology / Jeanéne Celesté Kotzé
. [Thesis]. North-West University; 2005. Available from: http://hdl.handle.net/10394/888
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
5.
Gibhard, Liezl.
The effect of Pheroid™ technology on the bioavailability of quinoline-based anti-malarial compounds in primates
.
Degree: 2012, North-West University
URL: http://hdl.handle.net/10394/9025
► Resistance against anti-malarial drugs remains one of the greatest obstacles to the effective control of malaria. The current first-line treatment regimen for uncomplicated P.falciparum malaria…
(more)
▼ Resistance against anti-malarial drugs remains one of the greatest obstacles to the effective control of malaria. The current first-line treatment regimen for uncomplicated P.falciparum malaria is based on artemisinin combination therapies (ACTs). However, reports of an increase in tolerance of the malaria parasite to artemisinins used in ACTs have alarmed the malaria community. The spread of artemisinin-resistant parasites would impact negatively on malaria control.
Chloroquine and amodiaquine are 4-aminoquinolines. Chloroquine and amodiaquine were evaluated in a primate model by comparing the bioavailability of these compounds in a reference formulation and also in a Pheroid® formulation. In vivo pharmacokinetic studies were conducted for chloroquine, and in vitro and in vivo drug metabolism and pharmacokinetic (DMPK) studies were conducted for amodiaquine. Pheroid® technology forms the basis of a colloidal drug delivery system, and it is the potential application of this technology in combination with the 4-aminoquinolines that was the focus of this thesis. Pheroid® is a registered trademark but for ease of reading will be referred to as pheroid(s) or pro-pheroid(s) throughout the rest of the thesis.
The non-human primate model used for evaluation of the pharmacokinetic parameters was the vervet monkey (Chlorocebus aethiops). Chloroquine was administered orally at 20 mg/kg. A sensitive and selective LC-MS/MS method was developed to analyze the concentration of chloroquine in both whole blood and plasma samples. The Cmax obtained for whole blood was 1039 ± 251.04 ng/mL for the unformulated reference sample of chloroquine and 1753.6 ± 382.8 ng/mL for the pheroid formulation. The AUC0-inf was 37365 ± 6383 ng.h/mL (reference) and 52047 ± 11210 ng.h/mL (pheroid). The results indicate that the use of pheroid technology enhances the absorption of chloroquine. The effect of pheroid technology on the bioavailability of amodiaquine and N-desethylamodiaquine was determined in two groups of vervet monkeys, with the reference group receiving capsules containing the hydrochloride salt of amodiaquine and the test group receiving capsules containing a pro-pheroid formulation of amodiaquine. Amodiaquine was administered at 60 mg/kg. Blood concentrations of amodiaquine and N-desethylamodiaquine samples were monitored over 13 time points from 0.5 to 168 hours. Amodiaquine and pro-pheroid formulated amodiaquine were incubated in vitro with human and monkey liver (HLM and MLM) and intestinal (HIM and MIM) microsomes and recombinant cytochrome P450 enzymes. The in vitro metabolism studies confirm the rapid metabolism of amodiaquine to the main metabolite N-desethylamodiaquine in monkeys. Although the pharmacokinetic parameters varied greatly, parameters for both the parent compound and main metabolite were lower in the test formulation compared to the reference formulation. For HLM, MLM and CYP2C8, the pro-pheroid test formulation showed significantly longer amodiaquine clearance and slower formation of N-desethylamodiaquine.…
Subjects/Keywords: Malaria;
Chloroquine,;
Amodiaquine,;
Pheroid® technology;
In vivo pharmacokinetic analysis;
In vitro metabolism;
Non-human primates;
Chlorokien;
Amodiakien;
Pheroid® tegnologie;
In vivo farmakokinetiese analise;
In vitro metabolisme;
Primate
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Gibhard, L. (2012). The effect of Pheroid™ technology on the bioavailability of quinoline-based anti-malarial compounds in primates
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/9025
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Gibhard, Liezl. “The effect of Pheroid™ technology on the bioavailability of quinoline-based anti-malarial compounds in primates
.” 2012. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/9025.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Gibhard, Liezl. “The effect of Pheroid™ technology on the bioavailability of quinoline-based anti-malarial compounds in primates
.” 2012. Web. 16 Apr 2021.
Vancouver:
Gibhard L. The effect of Pheroid™ technology on the bioavailability of quinoline-based anti-malarial compounds in primates
. [Internet] [Thesis]. North-West University; 2012. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/9025.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Gibhard L. The effect of Pheroid™ technology on the bioavailability of quinoline-based anti-malarial compounds in primates
. [Thesis]. North-West University; 2012. Available from: http://hdl.handle.net/10394/9025
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
6.
Benade, Reinette.
Formulation, in vitro release and transdermal diffusion of isoniazide and rifampicin for dermal tuberculosis / Reinette Benade
.
Degree: 2009, North-West University
URL: http://hdl.handle.net/10394/3982
► Extra pulmonary tuberculosis makes up 10% of all tuberculosis cases and cutaneous tuberculosis (CTB) only a fraction of this 10%. CTB is caused by mainly…
(more)
▼ Extra pulmonary tuberculosis makes up 10% of all tuberculosis cases and cutaneous tuberculosis (CTB) only a fraction of this 10%. CTB is caused by mainly Mycobacterium tuberculosis and can lead to scarring and deformities. The disease presents in different forms, from superficial granulomas to deeper ulceration and necrosis. Tissue cultures, polymerase chain reactions or purified protein derivative staining is used for the diagnosis of CTB (Barbagallo etal., 2002:320).
Since the current treatment for CTB is oral anti-tubercular regimens and no topical treatment is available yet (Barbagallo et a!., 2002:320), this study aims to provide a topical preparation of isoniazide and rifampicin which will prevent the deformities and scarring caused by CTB and deliver quicker healing. This topical preparation is to be used in addition to oral treatment. Isoniazide and rifampicin are powerful first-line anti-tubercular drugs, active against both intra- and extracellular bacteria (SAMF, 2005:293).
Human skin is a resistant and protective barrier against the external environment and the stratum corneum is the main barrier against diffusion of compounds through the skin (Williams, 2003:9). The physicochemical characteristics (lipophilicity and molecular size) of neither isoniazide nor rifampicin are optimal for penetration of the stratum corneum and the skin-friendly Pheroid™ delivery system was incorporated in two of the formulations to investigate the possibility of improving drug delivery.
In this study the transdermal delivery of isoniazide and rifampicin was studied after formulation into four different topical preparations. The stability of these formulations were determined over a six month period under three different conditions of temperature and humidity (25°C/60% RH (relative humidity), 30°C/60% RH and 40°C/75% RH). Isoniazide and rifampicin were formulated into two Pheroid™ and two non-Pheroid™ spray formulations: lotion, Pheroid™ lotion, emulgel and Pheroid™ emulgel. Micrographs were taken with a confocal laser scanning microscope and it was seen that the formulations were homogenous and oil droplets were smaller than 10 urn, allowing permeation through skin.
Vertical Franz diffusion cells were used for in vitro permeation studies, with cellulose acetate membranes, for 12 h periods at pH 7.4, to determine drug release. The donor phase was the formulation, with 5 mg/ml of isoniazide and 10 mg/ml of rifampicin. The actives were released from the formulations and small concentrations penetrated the membranes. Release for isoniazide was best from the Pheroid™ emulgel and for rifampicin from the Pheroid™ lotion. Thus it can be concluded that the Pheroid™ improved drug release.
The diffusion study was repeated, substituting the membranes with female abdominal skin in order to investigate transdermal delivery. Isoniazide and rifampicin failed to permeate the skin from any of the formulations and no isoniazide or rifampicin could be found in the skin by means of tape stripping after 12 h.
Stability tests performed…
Subjects/Keywords: Cutaneous tuberculosis;
Transdermal delivery;
Pheroid;
Vertical Franz cells;
Diffusion study;
Stability testing
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Benade, R. (2009). Formulation, in vitro release and transdermal diffusion of isoniazide and rifampicin for dermal tuberculosis / Reinette Benade
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/3982
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Benade, Reinette. “Formulation, in vitro release and transdermal diffusion of isoniazide and rifampicin for dermal tuberculosis / Reinette Benade
.” 2009. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/3982.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Benade, Reinette. “Formulation, in vitro release and transdermal diffusion of isoniazide and rifampicin for dermal tuberculosis / Reinette Benade
.” 2009. Web. 16 Apr 2021.
Vancouver:
Benade R. Formulation, in vitro release and transdermal diffusion of isoniazide and rifampicin for dermal tuberculosis / Reinette Benade
. [Internet] [Thesis]. North-West University; 2009. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/3982.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Benade R. Formulation, in vitro release and transdermal diffusion of isoniazide and rifampicin for dermal tuberculosis / Reinette Benade
. [Thesis]. North-West University; 2009. Available from: http://hdl.handle.net/10394/3982
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
7.
Ludick, Charlene Ethel.
The development of an oral single dose emulgel formulation for Pheroid® technology / Charlene Ethel Ludick
.
Degree: 2014, North-West University
URL: http://hdl.handle.net/10394/12246
► Dosage forms have been developed over the years for various applications. The dosage form consists of the active drug in combination with pharmaceutical excipients. The…
(more)
▼ Dosage forms have been developed over the years for various applications. The dosage form consists of the active drug in combination with pharmaceutical excipients. The pharmaceutical excipients solubilise, suspend, thicken, dilute, emulsify, stabilise, preserve, colour and flavour medicinal agents into efficacious and appealing dosage forms.
The dosage form under investigation in this study is of the oral type. The Pheroid® is a unique drug delivery system which consists of an oil-in-water emulsion system. Emulsion based drug systems provide a suitable medium for the delivery of both hydrophobic and hydrophilic drugs which can be incorporated into its oil or water phase for delivery to the site of action. These advantages make them more efficient as dosage form.
Emulgels are either emulsion of oil-in-water or water-in-oil type, which is gelled by mixing with gelling agents. Incorporation of emulsion into gel increases its stability and makes it a dual control release system. The presence of the gel phase makes it a non-greasy formulation which favours good patient compliance. A strategy followed to improve the stability of the emulgel system is the packaging of the formula into single dose sachets to protect the product against physical and chemical breakdown during patient usage. All factors such as selection of gelling agent, preservatives and formulation methods influencing the stability and efficacy of Pheroid® emulgel are discussed.
In this study, three different emulsifiers were added to the formula and the analysis of visual appearance, pH measurements, rheological studies, light microscopy and confocol laser scanning microscopy (CLSM) will provide an insight to the potential usage of emulgel as drug delivery system. A range of para-hydroxybenzoate esters was tested in the Pheroid® emulgel and the most suitable candidate chosen for further accelerated stability testing. It was thus possible to prepare a single dose emulgel with Carbopol® 934P (0.2% w/v) as an emulsifier, with Nipastat® (0.175% w/v) and PG (10% v/v) as preservatives into a stable dosage form suitable for further product development.
Subjects/Keywords: Development;
Oral;
Dosage form;
Emulgel;
Pheroid®;
Stability;
Nipastat®;
Carbopol® 934P;
Ontwikkeling;
Orale;
Doseervorm;
Stabiliteit
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ludick, C. E. (2014). The development of an oral single dose emulgel formulation for Pheroid® technology / Charlene Ethel Ludick
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/12246
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Ludick, Charlene Ethel. “The development of an oral single dose emulgel formulation for Pheroid® technology / Charlene Ethel Ludick
.” 2014. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/12246.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Ludick, Charlene Ethel. “The development of an oral single dose emulgel formulation for Pheroid® technology / Charlene Ethel Ludick
.” 2014. Web. 16 Apr 2021.
Vancouver:
Ludick CE. The development of an oral single dose emulgel formulation for Pheroid® technology / Charlene Ethel Ludick
. [Internet] [Thesis]. North-West University; 2014. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/12246.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Ludick CE. The development of an oral single dose emulgel formulation for Pheroid® technology / Charlene Ethel Ludick
. [Thesis]. North-West University; 2014. Available from: http://hdl.handle.net/10394/12246
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
8.
Swanepoel, Abraham Johannes.
Radio-labelling as a tool to investigate the absorption and bio-distribution of selected antimalarial drugs / Abraham Johannes Swanepoel
.
Degree: 2014, North-West University
URL: http://hdl.handle.net/10394/15591
► Previous studies have shown that the formulation of an active pharmaceutical ingredient (API) entrapped in the Pheroid® (Pheroid for simplification) delivery system enhances absorption of…
(more)
▼ Previous studies have shown that the formulation of an active pharmaceutical ingredient (API) entrapped in the Pheroid® (Pheroid for simplification) delivery system enhances absorption of the API, suppresses its metabolism, and may contribute to an increase in the quantity of the API present at the site of action. Higher drug levels at the active site should particularly increase the effectiveness of a drug with a narrow therapeutic index and reduce the incidence of the resistance that may otherwise arise if the sub-therapeutic levels of the API are in contact with the site of interest.
Two approaches were followed in this study. First, the radioactive tracer molecule 99mTechnetium methylene diphosphonate (99mTc MDP) was used. Intravenously injected 99mTc MDP is an extremely effective bone-seeking radiopharmaceutical used in the diagnosis of bone disorders such as bone metastases in patients. However, if entrapped inside a Pheroid vesicle, it will locate to that site, usually an organ, where the Pheroid vesicles may tend to accumulate. Experiments conducted with 99mTc MDP alone or with Pheroid will therefore establish how efficiently Pheroid vesicles localize and will also indicate the preferred site of localization inside a body. The process would involve the oral administration of 99mTc MDP either alone or with Pheroid, involving an animal model. It would also involve tracking localization to particular organs, blood or other sites. The second approach requires the use of chloroquine (CQ) labeled with carbon-14 (14C-CQ,) to compare absorption of the drug both with and without the Pheroid system.
The intention was to compare oral absorption and bio-distribution of 14C-CQ administered either alone or entrapped in the Pheroid system. It was also possible to establish whether the Pheroid affects the biological half-lives of the CQ and residence times of CQ in the different organs of the body.
Absorption of free 99mTc MDP (orally adminsistered) through the intestinal tract is negligible but it was anticipated that increased absorption will be observed when 99mTc MDP was
entrapped in the Pheroid system. In the 99mTc MDP study, different routes of administration of 99mTc MDP, as well as 99mTc MDP entrapped and not entrapped in the Pheroid system, were investigated. The Sprague Dawley rat was used as animal model. Rats were divided into three groups of four rats each for the first part of the study. In the first group, only 99mTc MDP was injected intravenously in order to establish natural distribution of the 99mTc MDP. For the second group, 99mTc MDP was administered orally in order to establish whether there was any absorption through the intestinal tract. In the third group, the 99mTc MDP was entrapped in Pheroid vesicles and this formulation was administered orally in order to establish whether the Pheroid system enhanced oral absorption. The animals were sacrificed four hours after administration and organs were harvested and were counted for radioactivity to determine the percentage of injected/administrated dose…
Subjects/Keywords: Pheroid;
99mTechnetium Methylene-diphosphate (99mTc MDP);
14C-Chloroquine;
Malaria;
Radiotracers;
Drug delivery
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Swanepoel, A. J. (2014). Radio-labelling as a tool to investigate the absorption and bio-distribution of selected antimalarial drugs / Abraham Johannes Swanepoel
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/15591
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Swanepoel, Abraham Johannes. “Radio-labelling as a tool to investigate the absorption and bio-distribution of selected antimalarial drugs / Abraham Johannes Swanepoel
.” 2014. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/15591.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Swanepoel, Abraham Johannes. “Radio-labelling as a tool to investigate the absorption and bio-distribution of selected antimalarial drugs / Abraham Johannes Swanepoel
.” 2014. Web. 16 Apr 2021.
Vancouver:
Swanepoel AJ. Radio-labelling as a tool to investigate the absorption and bio-distribution of selected antimalarial drugs / Abraham Johannes Swanepoel
. [Internet] [Thesis]. North-West University; 2014. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/15591.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Swanepoel AJ. Radio-labelling as a tool to investigate the absorption and bio-distribution of selected antimalarial drugs / Abraham Johannes Swanepoel
. [Thesis]. North-West University; 2014. Available from: http://hdl.handle.net/10394/15591
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
9.
Nell, Dirkie Cornelia.
Formulation and topical delivery of lidocaine and prilocaine with the use of Pheroid™ technology / Dirkie Cornelia Nell.
Degree: 2012, North-West University
URL: http://hdl.handle.net/10394/9809
► Local anaesthetics are used regularly in the medical world for a variety of different procedures. Topical anaesthetics are used largely in minor skin breaking procedures,…
(more)
▼ Local anaesthetics are used regularly in the medical world for a variety of different procedures. Topical anaesthetics are used largely in minor skin breaking procedures, laceration repair and minor surgical procedures such as laryngoscopy, oesophagoscopy or urethroscopy (Franchi et al., 2008:186e1). The topical means of application of a local anaesthetic is non-invasive and painless that results in a good patient acceptability profile (Little et al., 2008:102). An existing commercial topical anaesthetic product contains a eutectic mixture of the amide-type local anaesthetics lidocaine hydrochloride (HCl) and prilocaine hydrochloride (HCl). This commercial product takes up to an hour to produce an anaesthetic effect. This is considered as a disadvantage in the use of topical anaesthetics, an hour waiting time is not always ideal in certain medical circumstances (Wahlgren & Quiding, 2000:584).
This study compared the lag times, transdermal and topical delivery of lidocaine HCl and prilocaine HCl from four different semi-solid formulations with the inclusion of a current commercial product. One of the formulated semi-solid formulations included Pheroid™ technology, a novel skin-friendly delivery system developed by the Unit for Drug Research and Development at the North-West University, Potchefstroom Campus, South Africa.
The skin is the body’s first line of defence against noxious external stimuli. It is considered the largest organ in the body with an intensive and complex structure. It consists of five layers with the first outer layer, the stratum corneum, the most impermeable (Williams, 2003:1). The stratum corneum has excellent barrier function characteristics and is the cause for the time delay in the transdermal delivery of active pharmaceutical ingredients (API) (Barry, 2007:569). Local anaesthetics need to penetrate all the epidermal skin layers in order to reach their target site, the dermis. Skin appendages as well as blood vessels and skin nerve endings are located in the dermis. Local anaesthetics have to reach the free nerve endings in the dermis in order to cause a reversible block on these nerves for a local anaesthetic effect (Richards & McConachie, 1995:41).
Penetration enhancement strategies for the transdermal delivery of lidocaine and prilocaine have been investigated and include methods like liposomal entrapment (Franz-Montan et al., 2010; Müller et al., 2004), micellisation (Scherlund et al., 2000), occlusive dressing (Astra Zeneca, 2006), heating techniques (Masud et al., 2010) and iontophoresis (Brounéus et al., 2000). The Pheroid™ delivery system has improved the transdermal delivery of several compounds with its enhanced entrapment capabilities. Pheroid™ consists mainly of unsaturated essential fatty-acids, non-harmful substances that are easily recognised by the body (Grobler et al., 2008:285). The morphology and size of Pheroid™ is easily manipulated because it is a submicron emulsion type formulation which provides it with a vast flexibility profile (Grobler et al., 2008:284).…
Subjects/Keywords: Lidocaine HCl;
prilocaine HCl;
Pheroid™;
transdermal;
local anaesthesia;
dermis;
lidokaïenhidrochloried;
prilokaïenhidrochloried;
transdermale aflewering;
lokale verdower
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Nell, D. C. (2012). Formulation and topical delivery of lidocaine and prilocaine with the use of Pheroid™ technology / Dirkie Cornelia Nell.
(Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/9809
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Nell, Dirkie Cornelia. “Formulation and topical delivery of lidocaine and prilocaine with the use of Pheroid™ technology / Dirkie Cornelia Nell.
” 2012. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/9809.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Nell, Dirkie Cornelia. “Formulation and topical delivery of lidocaine and prilocaine with the use of Pheroid™ technology / Dirkie Cornelia Nell.
” 2012. Web. 16 Apr 2021.
Vancouver:
Nell DC. Formulation and topical delivery of lidocaine and prilocaine with the use of Pheroid™ technology / Dirkie Cornelia Nell.
[Internet] [Thesis]. North-West University; 2012. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/9809.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Nell DC. Formulation and topical delivery of lidocaine and prilocaine with the use of Pheroid™ technology / Dirkie Cornelia Nell.
[Thesis]. North-West University; 2012. Available from: http://hdl.handle.net/10394/9809
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
10.
Grobler, Lizette.
The effect of Pheroid® technology on the bioavailability of artemisone in primates / Lizette Grobler
.
Degree: 2014, North-West University
URL: http://hdl.handle.net/10394/12241
► Malaria is one the world’s most devastating diseases. Several classes of drugs are used to treat malaria. Artemisinin combination therapy is the first line treatment…
(more)
▼ Malaria is one the world’s most devastating diseases. Several classes of drugs are used to
treat malaria. Artemisinin combination therapy is the first line treatment of uncomplicated
malaria. The artemisinin derivative, artemisone in conjunction with the Pheroid® drug
delivery system, is the focus of this thesis.
The impact of the Pheroid® on the bioavailability of artemisone was evaluated in vervet
monkeys. The resulting artemisone plasma levels were much lower (Cmax of 47 and 114
ng/mL for reference and Pheroid® test formulations respectively) than expected for the
dosages administered (60 mg/kg). The Pheroid® improved the pharmacokinetic profile of
artemisone in a clinically significant manner. The metabolism of artemisone was assessed
in vitro by using human and monkey liver and intestinal microsomes, and recombinant
CYP3A4 enzymes. The Pheroid® inhibits the microsomal metabolism of artemisone. In
addition, there is a species difference in artemisone metabolism between man and monkey
since the in vitro intrinsic clearance of the reference formulation with monkey liver
microsomes is ~8 fold higher in the monkey liver microsomes compared to the human liver
microsomes and the estimated in vivo hepatic clearance for the monkey is almost twofold
higher than in humans.
Artemisone has potent antimalarial activity. Its in vitro efficacy was approximately twofold
higher than that of either artesunate or dihydroartemisinin when evaluated against P.
falciparum W2, D6, 7G8, TM90-C2B, TM91-C235 and TM93-C1088 parasite strains. The
Pheroid® drug delivery system did not improve or inhibit the in vitro efficacy of artemisone or
DHA. Artemisone (reference and Pheroid® test formulations) and metabolite M1 abruptly
arrested the growth of P. falciparum W2 parasites and induced the formation of dormant ring
stages in a manner similar to that of DHA.
Interaction of artemisone with the p-glycoprotein (p-gp) efflux transporter was investigated.
Artemisone stimulates ATPase activity in a concentration-dependent manner, whereas the
Pheroid® inhibited this p-gp ATPase activity. P-gp ATPase activity stimulation was fourfold
greater in human than cynomolgus monkey MDR1 expressed insect cell membranes.
Artemisone alone and artemisone entrapped in Pheroid® vesicles showed moderate apical
to basolateral and high basolateral to apical permeability (Papp) across Caco-2 cells. The
Papp efflux ratio of artemisone and artemisone entrapped in Pheroid® vesicles were both >5,
and decreased to ~1 when the p-gp inhibitor, verapamil, was added. Therefore, artemisone
is a substrate for mammalian p-gp. The cytotoxic properties of Pheroid® on Caco-2 cells
were assessed and the pro-Pheroid® seems to be non-toxic at concentrations of 1.25%. Vervet monkey plasma caused antibody-mediated growth inhibition of P. falciparum. Heat
inactivated or protein A treatment proved useful in the elimination of the growth-inhibitory
activity of the drug-free plasma. Plasma samples containing artemisone could not be
analysed by the ex-vivo…
Subjects/Keywords: Artemisone;
Bioavailability;
Clearance;
Drug delivery;
Efficacy;
Malaria;
Metabolism;
Monkey;
Pheroid®;
Aap;
Artemisoon;
Biobeskikbaarheid;
Effektiwiteit geneesmiddel aflewering;
Metabolisme;
Opruiming
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Grobler, L. (2014). The effect of Pheroid® technology on the bioavailability of artemisone in primates / Lizette Grobler
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/12241
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Grobler, Lizette. “The effect of Pheroid® technology on the bioavailability of artemisone in primates / Lizette Grobler
.” 2014. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/12241.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Grobler, Lizette. “The effect of Pheroid® technology on the bioavailability of artemisone in primates / Lizette Grobler
.” 2014. Web. 16 Apr 2021.
Vancouver:
Grobler L. The effect of Pheroid® technology on the bioavailability of artemisone in primates / Lizette Grobler
. [Internet] [Thesis]. North-West University; 2014. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/12241.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Grobler L. The effect of Pheroid® technology on the bioavailability of artemisone in primates / Lizette Grobler
. [Thesis]. North-West University; 2014. Available from: http://hdl.handle.net/10394/12241
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
11.
Langley, Natasha.
Preclinical evaluation of the possible enhancement of the efficacy of anti-malarial drugs by pheroid technology / Natasha Langley
.
Degree: 2007, North-West University
URL: http://hdl.handle.net/10394/1521
► Malaria is currently one of the most imperative parasitic diseases of the developing world. Current effective treatment options are limited because of increasing drug resistance,…
(more)
▼ Malaria is currently one of the most imperative parasitic diseases of the developing world. Current effective treatment options are limited because of increasing drug resistance, treatment cost effectiveness and treatment availability. Novel drug delivery systems are a new approach for increased efficacy in the treatment of the disease. Pheroid™ technology, a proven drug delivery system, in combination with anti-malarial drugs was evaluated in this study. The aim of this study was to evaluate the possible enhancement of the efficacy of the existing anti-malarial drugs in combination with Pheroid™ technology.
The efficacy of existing anti-malarial drugs in combination with Pheroids was investigated in vitro with a chloroquine RB-1-resistant strain of P. falciparum. Two different Pheroid formulations, vesicles and microsponges, were used and the control medium consisted of sterile water for injection. Parasitaemia levels were determined microscopically and expressed as a percentage. An in vivo pilot study was also conducted using the P. berghei mouse model. The mice were grouped into seven batches of three mice each. The control group was treated with a Pheroid vesicle formulation only. Three of the groups were treated with three different concentrations of chloroquine dissolved in water namely 2 mg/kg; 5 mg/kg and 10 mg/kg bodyweight (bw) respectively, while the other three groups received the same three concentrations of chloroquine entrapped in Pheroid vesicle formulations. The measure of parasite growth inhibition (percentage parasitaemia), the survival rates and the percentage chemosuppresion was determined. In the in vivo study, all concentrations of chloroquine entrapped in Pheroid vesicles showed suppressed parasitaemia levels up to 11 days post infection. From day 11, the parasitaemia increases rapidly and becomes higher than that in groups treated with chloroquine in water. Chloroquine entrapped in Pheroid vesicles showed improved activity against a chloroquine resistant strain (RB-1) in vitro. The efficacy was enhanced by 1544.62%. The efficacy of mefloquine, artemether and artesunate in Pheroid microsponges were enhanced by 314.32%, 254.86% and 238.78% respectively. It can be concluded that Pheroid™ technology has potential to enhance the efficacy of anti-malaria drugs.
Subjects/Keywords: Malaria;
Chloroquine;
Mefloquine;
Artemether;
Artesunate;
Pheroid technology;
P. falciparum
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Langley, N. (2007). Preclinical evaluation of the possible enhancement of the efficacy of anti-malarial drugs by pheroid technology / Natasha Langley
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/1521
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Langley, Natasha. “Preclinical evaluation of the possible enhancement of the efficacy of anti-malarial drugs by pheroid technology / Natasha Langley
.” 2007. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/1521.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Langley, Natasha. “Preclinical evaluation of the possible enhancement of the efficacy of anti-malarial drugs by pheroid technology / Natasha Langley
.” 2007. Web. 16 Apr 2021.
Vancouver:
Langley N. Preclinical evaluation of the possible enhancement of the efficacy of anti-malarial drugs by pheroid technology / Natasha Langley
. [Internet] [Thesis]. North-West University; 2007. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/1521.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Langley N. Preclinical evaluation of the possible enhancement of the efficacy of anti-malarial drugs by pheroid technology / Natasha Langley
. [Thesis]. North-West University; 2007. Available from: http://hdl.handle.net/10394/1521
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
12.
Van der Merwe, Helanie.
Evaluation and validation of in vitro assays to determine cell viability for HIV/AIDS expermentation with Pheroid TM technology / Helanie van der Merwe.
Degree: 2008, North-West University
URL: http://hdl.handle.net/10394/4171
► The Southern parts of Africa have the highest prevalence of HIV-infected people and South Africa is the country with the highest number of infections in…
(more)
▼ The Southern parts of Africa have the highest prevalence of HIV-infected people and
South Africa is the country with the highest number of infections in the world. There
is still no cure for AIDS, but anti-HIV medicine can prolong and enhance the quality of
life of an HIV infected person. Patient adherence with antiretroviral therapy is
extremely low due to difficult dosing intervals, problematic dosage forms, instability of
the antiretrovirals (ARVs) and the severe side-effects caused by these drugs; this
leads to resistance of HIV to these drugs.
Pheroid™ technology is a patented delivery system. Pheroid™ vesicles were used
during this study. The entrapment of an active within the Pheroid™ would generally
provide a safer, more effective formulation than the active alone. This could mean
that the amount of drug needed for treatment of HIV can be decreased while
producing fewer adverse effects and reducing the price of treatment.
The main objectives of this study were to optimise and validate the cell viability and
viral replication assays that can be used in an in vitro viral infection model. The MTT
assay was used to asses the viability of the cells and to determine the toxicity of the
antiretroviral drugs and Pheroid™ on the cells. HIV-1 assays were evaluated and
used to determine the viral replication in the cells.
Two different continuous cell lines were chosen for this study, an anchorage
dependent GHOST cell line and suspended M7-Luc cells. Both these cell lines were
best infected with the SWl virus. SWl is a subtype C, CXCR4 utilising virus.
Subtype C is responsible for 60 % of the HIV infections worldwide and is the
prevalent subtype in SUb-Saharan Africa .. Infection enhancers were not added to the
cells to improve viral infection since it was observed that the Pheroid™ in
combination with DEAE-dextran or Polybrene caused cytotoxicity probably by
disrupting the cell's membrane. Antioxidants were added to the Pheroid ™
formulation since it was observed that the viability of the cells incubated with the
Pheroid™ decreased as the Pheroid ™ matured. The added antioxidants had no
significant effect on the cells.
Abacavir (ABC) was chosen as the test substance for this study since it showed low
cytotoxicity in cell cultures and is water soluble and would not present solubility
issues in the media. It was entrapped within the Pheroid™ and its in vitro efficacy
and toxicity was tested on HIV-infected and uninfected cell cultures.
One directlHIV-specific (p24 antigen ELISA assay) and one indirect (Luciferase)
assays were used to asses the inhibition of HIV replication caused by ABC. The p24
antigen ELISA (Enzyme-Linked ImmunoSorbent Assay) assay required a lot of
washing steps and were rather expensive to use. The Luciferase assay was only
used on the M7-Luc cells; this assay was sensitive, inexpensive and easy to use.
The MTT (3-(4,5-demethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) viability
assay was used to measure the toxicity caused by the Pheroid ™ and/or ABC on the
cells. MTT is a widely used…
Subjects/Keywords: Abacavir (ABC);
HIV and AIDS;
Luciferase assay;
MTT;
p24 antigen ELISA assay;
Pheroid™;
viability;
MIV en VIGS;
Lewensvatbaarheid
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Van der Merwe, H. (2008). Evaluation and validation of in vitro assays to determine cell viability for HIV/AIDS expermentation with Pheroid TM technology / Helanie van der Merwe.
(Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/4171
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Van der Merwe, Helanie. “Evaluation and validation of in vitro assays to determine cell viability for HIV/AIDS expermentation with Pheroid TM technology / Helanie van der Merwe.
” 2008. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/4171.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Van der Merwe, Helanie. “Evaluation and validation of in vitro assays to determine cell viability for HIV/AIDS expermentation with Pheroid TM technology / Helanie van der Merwe.
” 2008. Web. 16 Apr 2021.
Vancouver:
Van der Merwe H. Evaluation and validation of in vitro assays to determine cell viability for HIV/AIDS expermentation with Pheroid TM technology / Helanie van der Merwe.
[Internet] [Thesis]. North-West University; 2008. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/4171.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Van der Merwe H. Evaluation and validation of in vitro assays to determine cell viability for HIV/AIDS expermentation with Pheroid TM technology / Helanie van der Merwe.
[Thesis]. North-West University; 2008. Available from: http://hdl.handle.net/10394/4171
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
13.
Van Zyl, Lindi.
Formulation and evaluation of different transdermal delivery systems with flurbiprofen as marker / Lindi van Zyl.
Degree: 2012, North-West University
URL: http://hdl.handle.net/10394/9727
► The aim of this study was to investigate the effect of different penetration enhancers containing essential fatty acids (EFAs) on the transdermal delivery of flurbiprofen.…
(more)
▼ The aim of this study was to investigate the effect of different penetration enhancers containing essential fatty acids (EFAs) on the transdermal delivery of flurbiprofen. Flurbiprofen was used as a marker / model compound. Fatty acids were chosen as penetration enhancers for their ability to reversibly increase skin permeability through entering the lipid bilayers and disrupting their ordered domains. Fatty acids are natural, non-toxic compounds (Karande & Mitragotri, 2009:2364). Evening primrose oil, vitamin F and Pheroid™ technology all contain fatty acids and were compared using a cream based-formulation. This selection was to ascertain whether EFAs exclusively, or EFAs in a delivery system, would have a significant increase in the transdermal delivery of a compound.
For an active pharmaceutical ingredient (API) to be effectively delivered transdermally, it has to be soluble in lipophilic, as well as hydrophilic mediums (Naik et al., 2000:319; Swart et al., 2005:72). This is due to the intricate structure of the skin, where the stratum corneum (outermost layer) is the primary barrier, which regulates skin transport (Barry, 2001:102; Moser et al., 2001:103; Venus et al., 2010:469). Flurbiprofen is highly lipophilic (log P = 4.24) with poor aqueous solubility. It has a molecular weight lower than 500 g/mol indicating that skin permeation may be possible, though the high log P indicates that some difficulty is to be expected (Dollery, 1999:F126; Hadgraft, 2004:292; Swart et al., 2005:72; Karande & Mitragotri, 2009:2363; Drugbank, 2012).
In vitro transdermal diffusion studies (utilising vertical Franz diffusion cells) were conducted, using donated abdominal skin from Caucasian females. The studies were conducted over 12 h with extractions of the receptor phase every 2 h to ensure sink conditions. Prior to skin diffusion studies, membrane release studies were performed to determine whether the API was released from the formulation. Membrane release studies were conducted over 6 h and extractions done hourly. Tape stripping experiments were performed on the skin circles after 12 h diffusion studies to determine the concentration flurbiprofen present in the stratum corneum and dermisepidermis. The flurbiprofen concentrations present in the samples were determined using high performance chromatography and a validated method.
Membrane release results indicated the following rank order for flurbiprofen from the different formulations: vitamin F > control > evening primrose oil (EPO) >> Pheroid™. The control formulation contained only flurbiprofen and no penetration enhancers. Skin diffusion results on the other hand, indicated that flurbiprofen was present in the stratum corneum and the dermisepidermis. The concentration flurbiprofen present in the receptor phase of the Franz cells (representing human blood) followed the subsequent rank order: EPO > control > vitamin F >> Pheroid™. All the formulations stipulated a lag time shorter than that of the control formulation (1.74 h), with the EPO formulation depicting the…
Subjects/Keywords: Fatty acid;
transdermal;
flurbiprofen;
vitamin F;
evening primrose oil;
Pheroid™;
vetsure;
transdermaal;
flurbiprofeen;
vitamien F;
nagkersolie
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Van Zyl, L. (2012). Formulation and evaluation of different transdermal delivery systems with flurbiprofen as marker / Lindi van Zyl.
(Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/9727
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Van Zyl, Lindi. “Formulation and evaluation of different transdermal delivery systems with flurbiprofen as marker / Lindi van Zyl.
” 2012. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/9727.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Van Zyl, Lindi. “Formulation and evaluation of different transdermal delivery systems with flurbiprofen as marker / Lindi van Zyl.
” 2012. Web. 16 Apr 2021.
Vancouver:
Van Zyl L. Formulation and evaluation of different transdermal delivery systems with flurbiprofen as marker / Lindi van Zyl.
[Internet] [Thesis]. North-West University; 2012. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/9727.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Van Zyl L. Formulation and evaluation of different transdermal delivery systems with flurbiprofen as marker / Lindi van Zyl.
[Thesis]. North-West University; 2012. Available from: http://hdl.handle.net/10394/9727
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
14.
De Bruyn, Tanile.
Nasal delivery of insulin with Pheroid technology / Tanile de Bruyn
.
Degree: 2006, North-West University
URL: http://hdl.handle.net/10394/730
► Approximately 350 million people worldwide suffer from diabetes mellitus (DM) and this number increases yearly. Since the discovery and clinical application of insulin in 1921,…
(more)
▼ Approximately 350 million people worldwide suffer from diabetes mellitus (DM) and this
number increases yearly. Since the discovery and clinical application of insulin in 1921,
subcutaneous injections have been the standard treatment for DM. Because insulin is hydrophilic
and has a high molecular weight and low bioavailability, this molecule is poorly absorbed if
administered orally.
The aim of this study is to evaluate nasal delivery systems for insulin, using Sprague Dawley rats
as the nasal absorption model. Pheroid technology and N-trimethyl chitosan chloride (TMC)
with different dosages of insulin (4, 8 and 12 IU/kg bodyweight insulin) was administered in the
left nostril of the rat by using a micropipette. Pheroid technology is a patented (North-West
University) carrier system consisting of a unique oil/water emulsion that actively transports drug
actives through various physiological barriers. These formulations were administered nasally to
rats in a volume of 100 p/kg bodyweight in different types of Pheroids (vesicles, with a size of
1.7 1 - 1.94 pm and microsponges, with a size of 5.7 1 - 8.25 pm).
The systemic absorption of insulin was monitored by measuring arterial blood glucose levels
over a period of 3 hours. The TMC formulation with 4 IU/kg insulin produced clinically relevant
levels of insulin in the blood and as a result also the maximal hypoglycaemic effect. TMC is a
quaternary derivative of chitosan and is able to enhance the absorption of various peptide drugs
by opening tight junctions between epithelial cells. Pheroid formulations were also effective in
lowering blood glucose levels but only at higher doses (8 and 12 IU/kg) of insulin. This study
indicated that Pheroid rnicrosponges had a faster onset of action and a slightly better absorption
of insulin when compared to Pheroid vesicles, but many more studies are needed in this field.
Although the results of this study with absorption enhancers are encouraging, nasal insulin
bioavailability is still very low, and the Pheroid formulations and long-term safety of nasal
insulin therapy have yet to be investigated.
Subjects/Keywords: Nasal delivery;
Insulin;
Absorption enhancers;
Pheroid vesicles;
Pheroid microsponges;
N-trimethyl chitosan chloride (TMC)
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
De Bruyn, T. (2006). Nasal delivery of insulin with Pheroid technology / Tanile de Bruyn
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/730
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
De Bruyn, Tanile. “Nasal delivery of insulin with Pheroid technology / Tanile de Bruyn
.” 2006. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/730.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
De Bruyn, Tanile. “Nasal delivery of insulin with Pheroid technology / Tanile de Bruyn
.” 2006. Web. 16 Apr 2021.
Vancouver:
De Bruyn T. Nasal delivery of insulin with Pheroid technology / Tanile de Bruyn
. [Internet] [Thesis]. North-West University; 2006. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/730.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
De Bruyn T. Nasal delivery of insulin with Pheroid technology / Tanile de Bruyn
. [Thesis]. North-West University; 2006. Available from: http://hdl.handle.net/10394/730
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
15.
Steyn, Johan Dewald.
Nasal delivery of recombinant human growth hormone with pheroid technology / Dewald Steyn
.
Degree: 2006, North-West University
URL: http://hdl.handle.net/10394/1276
► Over the past couple of years there has been rapid progress in the development and design of safe and effective delivery systems for the administration…
(more)
▼ Over the past couple of years there has been rapid progress in the development and design of
safe and effective delivery systems for the administration of protein and peptide drugs. The
effective delivery of these type of drugs are not always as simple as one may think, due to
various inherent characteristics of these compounds.
Due to the hydrophilic nature and molecular size of peptide and protein drugs, such as
recombinant human growth hormone, they are poorly absorbed across mucosal epithelia,
both transcellularly and paracellularly. This problem can be overcome by the inclusion of
absorption enhancers in peptide and protein drug formulations but this is not necessarily the
best method to follow.
This investigation focussed specifically on the evaluation of the ability of the PheroidTM
carrier system to transport recombinant human growth hormone across mucosal epithelia
especially when administered via the nasal cavity. The PheroidTM delivery system is a
patented system consisting of a unique submicron emulsion type formulation. The PheroidTM
delivery system, based on PheroidTM technology, will for ease of reading be called Pheroid(s)
only throughout the rest of this dissertation.
The Pheroid carrier system is a unique microcolloidal drug delivery system. A Pheroid is a
stable structure within a novel therapeutic system which can be manipulated in terms of
morphology, structure, size and function. Pheroids consist mainly of plant and essential fatty
acids and can entrap, transport and deliver pharmacologically active compounds and other
useful substances to the desired site of action.
The specific objectives of this study can be summarised as follows:
a literature study on Pheroid technology;
a literature study on chitosan and N-trimethyl chitosan chloride;
a literature study on recombinant human growth hormone (somatropin);
a literature study on nasal drug administration;
formulation of a suitable Pheroid carrier;
entrapment of somatropin in the Pheroid carrier, and
in vivo evaluation of nasal absorption of somatropin in Sprague-Dawley rats.
Subjects/Keywords: Recombinant human growth hormone (rhGH);
Pheroid vesicles;
Pheroid microsponges;
N-trimethyl chitosan chloride (TMC);
Nasal administration
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Steyn, J. D. (2006). Nasal delivery of recombinant human growth hormone with pheroid technology / Dewald Steyn
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/1276
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Steyn, Johan Dewald. “Nasal delivery of recombinant human growth hormone with pheroid technology / Dewald Steyn
.” 2006. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/1276.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Steyn, Johan Dewald. “Nasal delivery of recombinant human growth hormone with pheroid technology / Dewald Steyn
.” 2006. Web. 16 Apr 2021.
Vancouver:
Steyn JD. Nasal delivery of recombinant human growth hormone with pheroid technology / Dewald Steyn
. [Internet] [Thesis]. North-West University; 2006. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/1276.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Steyn JD. Nasal delivery of recombinant human growth hormone with pheroid technology / Dewald Steyn
. [Thesis]. North-West University; 2006. Available from: http://hdl.handle.net/10394/1276
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
16.
Coetzee, Hanneri.
The transdermal delivery of arginine vasopressin with pheroid technology / Hanneri Coetzee
.
Degree: 2007, North-West University
URL: http://hdl.handle.net/10394/1491
► The aim of this study was to investigate in vitro transdermal diffusion of a small peptide namely arginine vasopressin (AVP) with the aid of the…
(more)
▼ The aim of this study was to investigate in vitro transdermal diffusion of a small peptide namely
arginine vasopressin (AVP) with the aid of the novel PheroidTM drug delivery system. Generally,
peptides seem unfit for transdermal permeation, but it was thought prudent to explore the
suitability of this lipid-based system after success was achieved with entrapment of
tuberculostatics, bacteria and viruses. Bestatin (a selective aminopeptidase inhibitor) was
employed to circumvent any skin-related degradation of the active. Therefore, the effect of
bestatin on the preservation of AVP during diffusion was investigated. Vertical Franz cell
diffusion studies were conducted with female abdominal skin, with AVP at a concentration of
150 pglml in the donor phase and Hepes buffer as the receptor phase over a twelve-hour
period. To prove entrapment of AVP within the lipid structures of the PheroidsTM, fluorescentlylabelled
samples were monitored by means of confocal laser scanning microscopy (CLSM),
which revealed definite entrapment. In vitro permeation profiles for AVP exhibited a biphasic
character, with the majority of permeation occurring during the first two hours. The PheroidTM
delivery system proved to be advantageous when applied as delivery medium. The inclusion of
bestatin has an enhancing effect on permeation probably due to its protection of AVP.
Subjects/Keywords: Arginine vasopressin;
Transdermal diffusion;
Confocal microscopy;
Pheroid;
Delivery system;
Bestatin
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Coetzee, H. (2007). The transdermal delivery of arginine vasopressin with pheroid technology / Hanneri Coetzee
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/1491
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Coetzee, Hanneri. “The transdermal delivery of arginine vasopressin with pheroid technology / Hanneri Coetzee
.” 2007. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/1491.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Coetzee, Hanneri. “The transdermal delivery of arginine vasopressin with pheroid technology / Hanneri Coetzee
.” 2007. Web. 16 Apr 2021.
Vancouver:
Coetzee H. The transdermal delivery of arginine vasopressin with pheroid technology / Hanneri Coetzee
. [Internet] [Thesis]. North-West University; 2007. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/1491.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Coetzee H. The transdermal delivery of arginine vasopressin with pheroid technology / Hanneri Coetzee
. [Thesis]. North-West University; 2007. Available from: http://hdl.handle.net/10394/1491
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
17.
Botes, Adèle.
Transdermal delivery of isoniazid and rifampicin by pheroid technology / Adèle Botes
.
Degree: 2007, North-West University
URL: http://hdl.handle.net/10394/1668
► The aim of this in vitro study was to investigate the feasibility of the transdermal delivery of isoniazid (INH) and rifampicin (RMP) by means of…
(more)
▼ The aim of this in vitro study was to investigate the feasibility of the transdermal
delivery of isoniazid (INH) and rifampicin (RMP) by means of the novel PheroidTM
technology system. 'The application of the latter is being investigated in combination
with various actives such as peptides (insulin, human growth hormone), anti-malarial
drugs (chloroquine), anti-fungals (ketoconazole), local anaesthetics (lidocaine,
prilocaine) as well as tuberculostatics (ethambutol, pyrazinamide etc.) via different
administration routes at the North- West University.
PheroidTM, a stable skin-friendly carrier, comprises of a submicron (200 nm - 2 m)
emulsion type formulation for which previous studies have confirmed the ability to
penetrate keratinised tissue, skin, intestinal linings, the vascular system, fungi,
bacteria and even parasites. Studies involving an oral PheroidTM formulation
containing the current approved regime of four anti-tuberculosis drugs showed
improved efficacy results whilst an in vitro analysis of bacterial growth indicated a
reduction in drug resistance in multidrug resistant tuberculosis (MDR-TB) strains.
Therefore we thought it prudent to ascertain whether or not the PheroidTM system
would be able to improve the transdermal delivery of a combination of INH and RMP
as a possible treatment against cutaneous tuberculosis (tuberculosis involving the
skin). The latter refers to pathological lesions of the skin caused by any one of the
following: Mycobacterium tuberculosis, Mycobacterium bovis or the bacilli Calmette-
Guerin (BCG) vaccine. Demonstration of M. tuberculosis within the infected tissues
by traditional acid-fast bacilli (AFB) staining, culture or polymerase chain reaction
(PCR) confirms the diagnosis. CTB lesions are associated with various degrees of
one or more of the following ulceration, plaque formation, hyperkeratosis or the
presence of necrotic matter.
Seeing as C-TB is mostly associated with systemic involvement, current treatment
comprises of the standard three/four drug regimens used for pulmonary 'TB in
general. Cases of CTB usually show improvement within 1 month of therapy with
anti-TB drugs, but complete resolution is only attained after 4 - 6 months. 'The major
drawback to current therapy is that patients not only remain a source of infection
(viable organisms can still be demonstrated in the lesions), but they also suffer from constant embarrassment due to the disfiguring nature of CTB until these lesions have
healed completely. No evidence of an already existing topical formulation of this kind
could be found.
Therefore in vitro permeation studies were conducted using vertical Franz diffusion
cells and female abdominal skin as permeation membrane over a period of 12 hours.
Concentrations of 5 mg/ml and 10 mg/ml for isoniazid( INH) and rifampicin (RMP)
respectively, were applied to the donor phase suspended in either phosphate
buffered saline (PBS) or entrapped in PheroidTM. Permeation studies were
conducted at pH 5.5. In vitro penetration of INH…
Subjects/Keywords: Isoniazid;
Rifampicin;
Confocal laser scanning microscopy;
Pheroid;
Topical drug delivery;
Cutaneous tuberculosis;
Tuberculosis
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Botes, A. (2007). Transdermal delivery of isoniazid and rifampicin by pheroid technology / Adèle Botes
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/1668
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Botes, Adèle. “Transdermal delivery of isoniazid and rifampicin by pheroid technology / Adèle Botes
.” 2007. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/1668.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Botes, Adèle. “Transdermal delivery of isoniazid and rifampicin by pheroid technology / Adèle Botes
.” 2007. Web. 16 Apr 2021.
Vancouver:
Botes A. Transdermal delivery of isoniazid and rifampicin by pheroid technology / Adèle Botes
. [Internet] [Thesis]. North-West University; 2007. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/1668.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Botes A. Transdermal delivery of isoniazid and rifampicin by pheroid technology / Adèle Botes
. [Thesis]. North-West University; 2007. Available from: http://hdl.handle.net/10394/1668
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
18.
Slabbert, Chrizaan.
Evaluation and validation of methods to determine parasitemia in malaria cell cultures / Chrizaan Slabbert
.
Degree: 2008, North-West University
URL: http://hdl.handle.net/10394/2332
Subjects/Keywords: Malaria;
Mefloquine;
Chloroquine;
Pheroid technology;
P. falciparum;
Flow cytometry;
Colorimetric evaluation;
pLDH-method
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Slabbert, C. (2008). Evaluation and validation of methods to determine parasitemia in malaria cell cultures / Chrizaan Slabbert
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/2332
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Slabbert, Chrizaan. “Evaluation and validation of methods to determine parasitemia in malaria cell cultures / Chrizaan Slabbert
.” 2008. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/2332.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Slabbert, Chrizaan. “Evaluation and validation of methods to determine parasitemia in malaria cell cultures / Chrizaan Slabbert
.” 2008. Web. 16 Apr 2021.
Vancouver:
Slabbert C. Evaluation and validation of methods to determine parasitemia in malaria cell cultures / Chrizaan Slabbert
. [Internet] [Thesis]. North-West University; 2008. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/2332.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Slabbert C. Evaluation and validation of methods to determine parasitemia in malaria cell cultures / Chrizaan Slabbert
. [Thesis]. North-West University; 2008. Available from: http://hdl.handle.net/10394/2332
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
19.
Campbell, Berenice.
Pheroid technology for the topical delivery of depigmenting agents transforming growth factor–ß1 and tumor necrosis factor–a / Berenice Campbell
.
Degree: 2010, North-West University
URL: http://hdl.handle.net/10394/4739
► Pigmentation disorders occur in multiple conditions (Hakozaki et al., 2006:105). Although many modalities of treatments are available, none are completely satisfactory (Briganti et al., 2003:101).…
(more)
▼ Pigmentation disorders occur in multiple conditions (Hakozaki et al., 2006:105). Although many
modalities of treatments are available, none are completely satisfactory (Briganti et al.,
2003:101). Two cytokines normally present in the skin, transforming growth factor–beta1
(TGF–81) and tumour necrosis factor–alpha (TNF–9), have been shown to inhibit melanin
synthesis (Martinez–Esparza, 2001:972).
The stratum corneum has been commonly accepted as the main barrier to percutaneous
absorption. Many techniques have been applied to overcome this barrier properties and to
enhance penetration with varying success (Pellet et al., 1997:92).
The objective of this study was to investigate the topical delivery of the above mentioned
peptide drugs with aid of the Pheroid drug delivery system. Pheroid technology is a
delivery system that promotes the absorption and increases the efficacy of dermatological,
biological and oral medicines in various pharmacological groups (Grobler et al., 2008:4).
Pheroid entraps drugs with high efficiency and delivers them with remarkable speed to target
sites (Grobler, 2004:4). In order to avoid degradation of these peptides, bestatin hydrochloride
(an aminopeptidase inhibitor), was used (Lkhagvaa et al., 2008:386).
Topical drug delivery was achieved by means of vertical Franz cell diffusion studies performed
over a 6 and 12 h period. ELISA (enzyme linked immunosorbent assay) detection was used to
detect cytokine concentrations. Entrapped cytokine solutions were monitored by confocal laser
scanning microscopy (CLSM). Upon removal of donor and receptor compartments, skin discs
were subjected to tape stripping in order to establish the amount of active present within the
stratum corneum and epidermis as well as the remaining dermis (Pellet et al., 1997:92).
When comparing the two studies with each other, it is evident that the diffused concentration
values obtained with PBS (phosphate buffer solution, pH 7.4) was lower than that obtained with
the Pheroid drug delivery system. Both cytokine concentrations were successfully delivered
topically as a minimum of concentrations for both actives were detected. This positive result
was confirmed as well by the amount of active detected in stratum corneum–epidermis and
epidermis–dermis solutions.
Subjects/Keywords: Pigmentation;
Topical delivery;
Pheroid;
Transforming growth factor-beta1;
Tumour necrosis factor-alpha;
Bestatin;
Tape stripping;
Pigmentasie;
Topikale aflewering;
Transformerende groei faktor-beta1;
Tumor nekrosis faktor-alpha;
Bestatien;
Bandstroping
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Campbell, B. (2010). Pheroid technology for the topical delivery of depigmenting agents transforming growth factor–ß1 and tumor necrosis factor–a / Berenice Campbell
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/4739
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Campbell, Berenice. “Pheroid technology for the topical delivery of depigmenting agents transforming growth factor–ß1 and tumor necrosis factor–a / Berenice Campbell
.” 2010. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/4739.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Campbell, Berenice. “Pheroid technology for the topical delivery of depigmenting agents transforming growth factor–ß1 and tumor necrosis factor–a / Berenice Campbell
.” 2010. Web. 16 Apr 2021.
Vancouver:
Campbell B. Pheroid technology for the topical delivery of depigmenting agents transforming growth factor–ß1 and tumor necrosis factor–a / Berenice Campbell
. [Internet] [Thesis]. North-West University; 2010. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/4739.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Campbell B. Pheroid technology for the topical delivery of depigmenting agents transforming growth factor–ß1 and tumor necrosis factor–a / Berenice Campbell
. [Thesis]. North-West University; 2010. Available from: http://hdl.handle.net/10394/4739
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
20.
Botha, Mario Matthew.
Pre-clinical evaluation of the possible enhancement of the efficacy of antiretroviral drugs by pheroid technology / M.M. Botha
.
Degree: 2007, North-West University
URL: http://hdl.handle.net/10394/1064
► HIV/AIDS is the most threatening and challenging infectious diseases of our time, with the highest increase of newly infected cases reported. This infectious disease was…
(more)
▼ HIV/AIDS is the most threatening and challenging infectious diseases of our time, with the highest increase of newly infected cases reported. This infectious disease was discovered in the early eighties under homosexual men and was later to be discovered in heterosexuals. HIV is a systemic immunosuppressive disorder which causes a depletion of CD4+ T cells and develops into the acquired immunodeficiency syndrome - AIDS.
Africa is the continent most affected by HIV/AIDS with the southern parts of Africa having the highest prevalence rates compared to the rest of Africa. Statistics indicate that AIDS is responsible for 3% of deaths in children worldwide - one in seven people dying of an HIV-related illness is a child under the age of 15 years. It was stated by the WHO that countries should develop improved antiretrovirals regimes for the prevention of mother-to-child transmission.
Difficulties in administering antiretrovirals (ARVs) to patients (especially children) are the strict dosage regimes and the severe adverse reactions. These factors complicate patient adherence. The list of problems in treating patients is endless and includes the distribution, stability as well as the low efficacy of these drugs.
Most of the above mentioned problems and obstacles related to ARVs and ARV treatment could be minimized or eliminated by the use of a stable and effective drug delivery system. Enhancing ARV treatment may be accomplished by the use of the Pheroid™ drug delivery system. Pheroids™ consists mainly of fatty acids and sterile nitrous oxide gassed water. Pharmacological active substances are entrapped into submicron and micron sized structures called Pheroids™. Research showed promising results and advantages in delivering drugs through oral and transdermal routes using Pheroid™ technology.
The focus of this study was to test the possible enhancement of the efficacy of antiretrovirals using Pheroid™ technology. The assays used to study this possible enhancement were a modified neutral red and a modified 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay. These assays confirmed and illustrated the toxic and protective properties of the tested ARVs (stavudine, lamivudine and nevirapine). An MT-2 cell line was used and infected with an HIV-1 strain, SW7-TCL.
Applying Pheroid™ technology in these assays resulted in massive cell death, due to increased ARV toxic levels within the cells. Viability tests proved that Pheroids™ had no effect on the viability of cells at the concentration typically used. This confirmed the enhancing properties of Pheroids™ in the delivery of drugs into the cells. The MTT assay was further adapted from a seven day incubation period to a three day incubation period. By using a low concentration series and a three day incubation period the loss of cells through toxicity was partially overcome.
One of the problems that arose form this study was the non-reproducibility of the results. Absorbance levels fluctuated at specific concentrations of the same ARV, which cause…
Subjects/Keywords: Lamivudine (3TC);
Stavudine (d4T);
MTT;
Finter's neutral red;
Pheroid;
Antiretroviral (ARV);
HIV and AIDS;
Viability
Record Details
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Botha, M. M. (2007). Pre-clinical evaluation of the possible enhancement of the efficacy of antiretroviral drugs by pheroid technology / M.M. Botha
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/1064
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Botha, Mario Matthew. “Pre-clinical evaluation of the possible enhancement of the efficacy of antiretroviral drugs by pheroid technology / M.M. Botha
.” 2007. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/1064.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Botha, Mario Matthew. “Pre-clinical evaluation of the possible enhancement of the efficacy of antiretroviral drugs by pheroid technology / M.M. Botha
.” 2007. Web. 16 Apr 2021.
Vancouver:
Botha MM. Pre-clinical evaluation of the possible enhancement of the efficacy of antiretroviral drugs by pheroid technology / M.M. Botha
. [Internet] [Thesis]. North-West University; 2007. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/1064.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Botha MM. Pre-clinical evaluation of the possible enhancement of the efficacy of antiretroviral drugs by pheroid technology / M.M. Botha
. [Thesis]. North-West University; 2007. Available from: http://hdl.handle.net/10394/1064
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

North-West University
21.
Uys, Charlene Ethel.
Preparation and characterisation of pheroid vesicles / Charlene Ethel Uys
.
Degree: 2006, North-West University
URL: http://hdl.handle.net/10394/1669
► Pheroid is a patented system comprising of a unique submicron emulsion type formulation. Pheroid vesicles consist mainly of plant and essential fatty acids and can…
(more)
▼ Pheroid is a patented system comprising of a unique submicron emulsion type
formulation. Pheroid vesicles consist mainly of plant and essential fatty acids and
can entrap, transport and deliver pharmacologically active compounds and other
useful molecules. The aim of this study was to show that a modulation of
components and parameters is necessary to obtain the optimum formula to be used
in pharmaceutical preparations.
Non-optimal or non-predictable stability properties of emulsions can be limiting for the
applications of emulsions (Bjerregaard et al., 2001:23). Careful consideration was
given to the apparatus used during the processing along with the ratios of the various
components added to the formulation and the storage conditions of the Pheroid
vesicles.
A preliminary study was performed to optimize the most accurate processing
parameters during emulsification. The effect of emulsification rate and time, the
temperature of the aqueous phase, the number of days the water phase were
gassed, the concentration of the surfactant, cremophor® RH 40, used and the
concentration of Vitamin F Ethyl Ester CLR added to the oil phase of the o/w
emulsion has been studied. Quantification of the mean particle size, zeta potential,
turbidity, pH and current values were used to characterize the emulsions. The
samples were characterised after 1, 2, 3, 7, 14, 21 and 28 days of storage. The
emulsions were also characterised with confocal laser scanning microscopy (CLSM)
to measure the number and size and size distribution of the vesicles.
After determination of the processing variables influencing the emulsion stability an
accelerated stability test was conducted on a final formula. In the present study,
accelerated stability testing employing elevated temperatures and relative humidity
were used with good accuracy to predict long-term stability of an o/w emulsion kept
at both 5 and 25 OC with 60 % relative humidity and 40 OC with 75 % relative
humidity. The results of the stability tests were presented in histograms of the
physical properties 24 hours, 1 month, 2 months and 3 months after preparation of
the emulsion.
It was concluded that Pheroid vesicles demonstrate much potential as a drug delivery
system. The high stability of this formula allows its use in a wide variety of
applications in the pharmaceutical industry.
Subjects/Keywords: Pheroid;
Emulsion stability;
Particle size and size distribution;
Zeta potential;
Turbidity;
pH;
Current;
Confocal laser scanning microscope ( CLSM);
Accelerated stability testing
Record Details
Similar Records
Cite
Share »
Record Details
Similar Records
Cite
« Share





❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Uys, C. E. (2006). Preparation and characterisation of pheroid vesicles / Charlene Ethel Uys
. (Thesis). North-West University. Retrieved from http://hdl.handle.net/10394/1669
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Uys, Charlene Ethel. “Preparation and characterisation of pheroid vesicles / Charlene Ethel Uys
.” 2006. Thesis, North-West University. Accessed April 16, 2021.
http://hdl.handle.net/10394/1669.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Uys, Charlene Ethel. “Preparation and characterisation of pheroid vesicles / Charlene Ethel Uys
.” 2006. Web. 16 Apr 2021.
Vancouver:
Uys CE. Preparation and characterisation of pheroid vesicles / Charlene Ethel Uys
. [Internet] [Thesis]. North-West University; 2006. [cited 2021 Apr 16].
Available from: http://hdl.handle.net/10394/1669.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Uys CE. Preparation and characterisation of pheroid vesicles / Charlene Ethel Uys
. [Thesis]. North-West University; 2006. Available from: http://hdl.handle.net/10394/1669
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
.