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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Formulation, characterization and cellular toxicity of lipid based drug delivery systems for mefloquin / Chrizaan Helena (nee Slabbert)

Helena (nee Slabbert), Chrizaan January 2011 (has links)
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 conducted include haemolysis and ROS (reactive oxygen species) analysis on erythrocytes as well as cell viability on mouse neuroblastoma cells. Pheroid™ vesicles with and without mefloquine resulted in a dose dependent increase in ROS and haemolysis over time. A dose dependent increase in ROS and haemolysis in both liposome formulations were observed, but to a lesser extent. Mefloquine proved to be neurotoxic with similar results obtained when mefloquine was entrapped in liposomes. Pheroid™ vesicles seem to have neuroprotective properties resulting in higher cell viability. Mefloquine could be entrapped successfully in Pheroid™ vesicles and less in liposomes. Pheroid™ vesicles was more stable over a three months accelerated stability testing with more favourable characteristics. The increase in ROS levels of Pheroid™ vesicles could be responsible for the higher efficacy and haemolytic activity. DL-α-Tocopherol in Pheroid™ vesicles possibly acted as a pro-oxidant due to the presence of iron in the erythrocytes. DL-α-Tocopherol showed possible antioxidant properties in the neurotoxicity evaluation resulting in higher cell viability. Even though liposomes illustrated higher efficacy and little haemolysis and ROS production, no difference in neurotoxicity was observed together with unfavourable properties during stability testing makes this drug delivery system less favourable in comparison to Pheroid™ vesicles. Mefloquine was successfully incorporated into Pheroid™ vesicles resulted in high efficacy and showed possible neuroprotection and therefore makes it an ideal system for treatment of malaria. / Thesis (Ph.D. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2011
12

Quantifying the telecommunication opportunity at the base of the pyramid in South Africa : a retail perspective / Ignatius Meyer

Meyer, Ignatius January 2014 (has links)
This study focuses on the telecommunication industry, specifically the mobile phone market at the base of the pyramid (BOP). A supply vs. demand stance is taken whereby demographic data offer insight into the demand while the location of telecommunication retail stores constitutes supply. The study furthermore makes extensive use of a GIS (geographical information system) which offers deeper insight into data and different applications thereof. Given the extensive nature of the data used in assessing the national market, a dashboard was developed as part of this research to ease data interpretation. The online map (GIS) and dashboard form an integral part of this report. Literature supports the targeting of the BOP as a viable market given the high volume of people in this market segment. Unconventional methods are, however, required to sustainably cater to this market. The development of multiple channels to target potential consumers has resulted in a dilution of the market in the retail environment. The retail channel however remains important in any company’s strategy to target the BOP. Telecommunication companies can not only benefit from the BOP but also offer benefits to the BOP. The World Bank has reported figures that show a 0.8% increase in GDP for every 10% increase in mobile penetration. Different sources identify the BOP by different income ranges. It became evident, however, that internationally the average applied to identify the BOP is households earning less than USD 3,000 (ZAR 31,440 at an exchange rate of R10.48 / USD) per annum. Although somewhat higher than the international average, the available data dictated that South Africa’s BOP be identified as households earning less than R38,200 per annum for the purposes of this research. Data indicate that 89% of households in South Africa have a mobile phone. By comparing the ownership of existing household goods this research found that of the 11% of households not owning a mobile phone, 6% would be willing to adopt a mobile phone. A tiered approach is followed in assessing the telecommunication opportunity for mobile phones in the BOP. The first tier assesses the entire market (all households in South Africa) at a municipal level. By including the total market, the opportunity in the BOP is put into perspective. The result was that the total BOP market offers a potential market of R563 million per month through 13.7 simcards. At the other end of the economic pyramid, the ROP offers a market of R2416 million per month through 14.6 million simcards. Thus, even though the BOP offers 48% of the total volume in the market, the value is only 19% of the total market. From a coverage perspective, 42% of BOP households are not covered by a telecom retailer whilst only 27% of the ROP households are not covered. A market of R247 million (through 5.8 million simcards) has been estimated in the BOP opposed to a R379 million market (through 5.8 million simcards) in the ROP. The second tier makes use of a case study to determine the viability of targeting the BOP. Moruleng Mall’s catchment area was analysed within the Moses Kotane municipality that offered a high opportunity as determined in the first tier of analysis. This case study made use of gravity modelling and found that Rustenburg’s retail offering would have limited influence and as such telecom retailers would have to revisit their strategy for the area. A number of shopping centre developments in rural areas were highlighted. Effectively while these developments are taking retail closer to the BOP or rual population, the market is diluted. From a retailer perspective, this makes it difficult to target an entire area through presence in one specific retail node or town. The ultimate finding of this this research suggests that it is in fact possible to target the BOP – however, that it is the ROP located between the BOP households that makes this a viable market. This suggests that it is rather not a question of the viability in targeting the BOP specifically but targeting the more dense rural areas that offer opportunity. / MBA, North-West University, Potchefstroom Campus, 2014
13

Therapists' experiences in adopting technology as a therapeutic medium with children / Deborah Jean Cotton

Cotton, Deborah Jean January 2014 (has links)
Children, growing up in this digital era incorporate technology into play, communication and learning. Therapists working with children endeavour to use mediums with which children are familiar and thus need to make a decision whether to include technology in or exclude technology from their therapeutic environments. This is no easy decision, in the midst of negative publicity regarding the role technology plays in children‘s lives. A deeper understanding of what encourages or discourages therapists from using technology as a therapeutic medium with children could guide practitioners in their decisions regarding the use of technology in therapy. The aim of this study was to explore and describe experiences of therapists using technology, as a therapeutic medium with children. A qualitative multiple case study design was used. Experiences were defined as the “active process" of reinterpreting the "physical, perceptual, affective and cognitive aspects" of being exposed to events to bring about a change in response options (McKnight & Sechrest, 2003:471). Data were collected by means of semi-structured interviews and visual data. Seven therapists participated in the research, selected by means of non-probability purposive sampling and snowball sampling. Collected data and reflective field notes were analysed thematically, using an inductive, interpretive approach, guided by a theoretical framework, the Theory of Reasoned Action (TRA). Findings indicated that all participants were aware that children find technology appealing, but participants who were older or psychodynamically orientated were less inclined to incorporate technology as a therapeutic medium. Participants who were experimental by nature used technology as a therapeutic medium with some caution. Experimentally inclined participants who had received training in using technology used technology not only as a therapeutic medium, but also more confidently as a play medium. Participants were deterred mainly by the uncertainty of the therapeutic value of technology, the lack of ethical guidelines regulating the use of technology in therapy and the concern that technology may interfere with the therapeutic process. Further research regarding parents’ and child-clients’ perspectives of using technology in therapy would perhaps reduce speculative perceptions. Research regarding therapists’ values and perceptions of technology as a therapeutic medium could guide stakeholders in their development of training programs and necessary ethical guidelines. / MA (Psychology), North-West University, Potchefstroom Campus, 2015
14

'n Onderrigraamwerk om werktoegangvaardighede by rekenaartoepassingstegnologie-leerders te verbeter / Elsie Elizabeth Sophia Lubbe

Lubbe, Elsie Elizabeth Sophia January 2011 (has links)
Insufficiency in literacy is seen as a worldwide problem. The scope of the problem is confirmed by the fact that the United Nations declared the years 2003–2012 as International Literacy Decade. Literacy is seen as a necessary skill – the cornerstone of human capital development – and a fundamental competency on which the mastering of all other skills depends. Fundamental skills such as reading, writing and numeric skills and technological literacy influence the economic prosperity of any country in different ways. The language and numeric skills of learners are declining, and employers are of the opinion that candidates applying for work do not have sufficient basic skills for available jobs. The above has led to the decision to focus in this study on the development of a teaching framework for the improvement of job access skills for Grade 10 Computer Applications Technology (CAT) learners. The concepts of “literacy” and “job access” are discussed in the literature review. Job access skills are anchored in literacy. An analysis of the Grade 10 CAT learning programme and work schedule was done to determine to which degree literacy skills are addressed in the assessment standards. A framework and an accompanying workbook were developed in this study to address the gaps that were identified during the analysis of the Grade 10 teaching and learning programme and work schedule. Various requirements and determinants for the development of a teaching framework were studied. These requirements and determinants were considered for the development of the suggested teaching framework. A workbook containing literacy tasks was used to improve literacy skills of learners and was used as the instrument for the implementation of the teaching framework. The empirical study being reported here was aimed at determining to which degree the use of the workbook that had been developed as the instrument for the integration of the teaching framework, contributed to the improvement of the learners’ literacy skills. During the qualitative study, it was revealed that the teachers at the schools participating in this study were very positive about the workbook, and also that they were of the opinion that it could contribute to the improvement of the literacy skills of the learners. A practical significant influence with a large effect regarding general literacy and a small effect on general numeracy were reported. The analysis of the quantitative data showed that completion of the learning tasks in the workbook does indeed have an influence on improving the literacy level of the learners, and it is thus recommended that literacy skills be integrated into the existing CAT learning programme. / PhD (Teaching and Learning), North-West University, Potchefstroom Campus, 2012
15

Responsible use of social media by undergraduate student nurses / Ingrid van der Walt

Van der Walt, Ingrid January 2014 (has links)
The background and problem statement centre on the evolution of technology within teaching and learning, which involves undergraduate student nurses, as well as the use of social media as interactive teaching and communication tool. While examining the background to this topic, the researcher recognised a need to gain a deeper understanding of responsible social media use by undergraduate student nurses to the benefit of all the stakeholders, namely the Nursing Education Institution (NEI), applicable health care facilities, the patients and the student nurses. The study starts off with a literature review to peruse what is known about social media and information communication technology by undergraduate student nurses within a Higher Education (HE) environment. Literature shows that nurses in their work environment are not excluded from social media interaction processes. Within this context, social media offers improved contact and communication in general and in the working environment through the internet. The aim of this study is to explore and describe responsible use of social media by undergraduate student nurses. Methodology: The study followed a qualitative, explorative, descriptive and contextual design. All-inclusive, probable and purposive sampling (Brink, van der Walt & van Rensburg, 2006:134) was applied to select participants from a population of undergraduate student nurses (N=200, n=39). Prospective participants were informed by the researcher regarding the research by means of a Power Point slideshow and from there prospective participants had to make an informed decision to participate voluntarily in the research. Data was collected by means of an unstructured conversation between the researcher and participants via the real-time, online Chat Room of Sakai 2.9.1. Sakai 2.9.1 refers to an educational software platform which is a Java-based, service-oriented application used in an open source academic community. Sakai 2.9.1 is used within this context as a Course Management System and Virtual Learning Environment. The following questions were asked: “Tell me how you use your social media (e.g. Facebook™, Twitter™, WAYN™, LinkedIn™, WhatsApp™, etc.)”; “How do you access and on which device do you use social media?”, “What is your view of responsible social media use as a student nurse?” Although it was an all-inclusive sample and all members of the population were invited to participate, the sample size was established once the research reached data saturation (Brink et al., 2006:135). Thirty-nine participants (n=39) participated and the analysed results were first confirmed in a focus group. Six (6) main themes where identified, namely: social media as a quick academic reference; the social communication uses of social media; social curiosity; multiple social media registrations, but limited social media use; student nurses’ need for guidelines regarding responsible social media use and a need to share photographs on social media. The final conclusion was that student nurses entered the nursing profession with established social media skill. Yet, student nurses need guidance to divert social media use from a social perspective to social media use within a professional capacity. Recommendations for enhanced responsible social media use by student nurses where formulated. (Word count: 489) / MCur, North-West University, Potchefstroom Campus, 2014
16

Quantifying the telecommunication opportunity at the base of the pyramid in South Africa : a retail perspective / Ignatius Meyer

Meyer, Ignatius January 2014 (has links)
This study focuses on the telecommunication industry, specifically the mobile phone market at the base of the pyramid (BOP). A supply vs. demand stance is taken whereby demographic data offer insight into the demand while the location of telecommunication retail stores constitutes supply. The study furthermore makes extensive use of a GIS (geographical information system) which offers deeper insight into data and different applications thereof. Given the extensive nature of the data used in assessing the national market, a dashboard was developed as part of this research to ease data interpretation. The online map (GIS) and dashboard form an integral part of this report. Literature supports the targeting of the BOP as a viable market given the high volume of people in this market segment. Unconventional methods are, however, required to sustainably cater to this market. The development of multiple channels to target potential consumers has resulted in a dilution of the market in the retail environment. The retail channel however remains important in any company’s strategy to target the BOP. Telecommunication companies can not only benefit from the BOP but also offer benefits to the BOP. The World Bank has reported figures that show a 0.8% increase in GDP for every 10% increase in mobile penetration. Different sources identify the BOP by different income ranges. It became evident, however, that internationally the average applied to identify the BOP is households earning less than USD 3,000 (ZAR 31,440 at an exchange rate of R10.48 / USD) per annum. Although somewhat higher than the international average, the available data dictated that South Africa’s BOP be identified as households earning less than R38,200 per annum for the purposes of this research. Data indicate that 89% of households in South Africa have a mobile phone. By comparing the ownership of existing household goods this research found that of the 11% of households not owning a mobile phone, 6% would be willing to adopt a mobile phone. A tiered approach is followed in assessing the telecommunication opportunity for mobile phones in the BOP. The first tier assesses the entire market (all households in South Africa) at a municipal level. By including the total market, the opportunity in the BOP is put into perspective. The result was that the total BOP market offers a potential market of R563 million per month through 13.7 simcards. At the other end of the economic pyramid, the ROP offers a market of R2416 million per month through 14.6 million simcards. Thus, even though the BOP offers 48% of the total volume in the market, the value is only 19% of the total market. From a coverage perspective, 42% of BOP households are not covered by a telecom retailer whilst only 27% of the ROP households are not covered. A market of R247 million (through 5.8 million simcards) has been estimated in the BOP opposed to a R379 million market (through 5.8 million simcards) in the ROP. The second tier makes use of a case study to determine the viability of targeting the BOP. Moruleng Mall’s catchment area was analysed within the Moses Kotane municipality that offered a high opportunity as determined in the first tier of analysis. This case study made use of gravity modelling and found that Rustenburg’s retail offering would have limited influence and as such telecom retailers would have to revisit their strategy for the area. A number of shopping centre developments in rural areas were highlighted. Effectively while these developments are taking retail closer to the BOP or rual population, the market is diluted. From a retailer perspective, this makes it difficult to target an entire area through presence in one specific retail node or town. The ultimate finding of this this research suggests that it is in fact possible to target the BOP – however, that it is the ROP located between the BOP households that makes this a viable market. This suggests that it is rather not a question of the viability in targeting the BOP specifically but targeting the more dense rural areas that offer opportunity. / MBA, North-West University, Potchefstroom Campus, 2014
17

Therapists' experiences in adopting technology as a therapeutic medium with children / Deborah Jean Cotton

Cotton, Deborah Jean January 2014 (has links)
Children, growing up in this digital era incorporate technology into play, communication and learning. Therapists working with children endeavour to use mediums with which children are familiar and thus need to make a decision whether to include technology in or exclude technology from their therapeutic environments. This is no easy decision, in the midst of negative publicity regarding the role technology plays in children‘s lives. A deeper understanding of what encourages or discourages therapists from using technology as a therapeutic medium with children could guide practitioners in their decisions regarding the use of technology in therapy. The aim of this study was to explore and describe experiences of therapists using technology, as a therapeutic medium with children. A qualitative multiple case study design was used. Experiences were defined as the “active process" of reinterpreting the "physical, perceptual, affective and cognitive aspects" of being exposed to events to bring about a change in response options (McKnight & Sechrest, 2003:471). Data were collected by means of semi-structured interviews and visual data. Seven therapists participated in the research, selected by means of non-probability purposive sampling and snowball sampling. Collected data and reflective field notes were analysed thematically, using an inductive, interpretive approach, guided by a theoretical framework, the Theory of Reasoned Action (TRA). Findings indicated that all participants were aware that children find technology appealing, but participants who were older or psychodynamically orientated were less inclined to incorporate technology as a therapeutic medium. Participants who were experimental by nature used technology as a therapeutic medium with some caution. Experimentally inclined participants who had received training in using technology used technology not only as a therapeutic medium, but also more confidently as a play medium. Participants were deterred mainly by the uncertainty of the therapeutic value of technology, the lack of ethical guidelines regulating the use of technology in therapy and the concern that technology may interfere with the therapeutic process. Further research regarding parents’ and child-clients’ perspectives of using technology in therapy would perhaps reduce speculative perceptions. Research regarding therapists’ values and perceptions of technology as a therapeutic medium could guide stakeholders in their development of training programs and necessary ethical guidelines. / MA (Psychology), North-West University, Potchefstroom Campus, 2015
18

'n Onderrigraamwerk om werktoegangvaardighede by rekenaartoepassingstegnologie-leerders te verbeter / Elsie Elizabeth Sophia Lubbe

Lubbe, Elsie Elizabeth Sophia January 2011 (has links)
Insufficiency in literacy is seen as a worldwide problem. The scope of the problem is confirmed by the fact that the United Nations declared the years 2003–2012 as International Literacy Decade. Literacy is seen as a necessary skill – the cornerstone of human capital development – and a fundamental competency on which the mastering of all other skills depends. Fundamental skills such as reading, writing and numeric skills and technological literacy influence the economic prosperity of any country in different ways. The language and numeric skills of learners are declining, and employers are of the opinion that candidates applying for work do not have sufficient basic skills for available jobs. The above has led to the decision to focus in this study on the development of a teaching framework for the improvement of job access skills for Grade 10 Computer Applications Technology (CAT) learners. The concepts of “literacy” and “job access” are discussed in the literature review. Job access skills are anchored in literacy. An analysis of the Grade 10 CAT learning programme and work schedule was done to determine to which degree literacy skills are addressed in the assessment standards. A framework and an accompanying workbook were developed in this study to address the gaps that were identified during the analysis of the Grade 10 teaching and learning programme and work schedule. Various requirements and determinants for the development of a teaching framework were studied. These requirements and determinants were considered for the development of the suggested teaching framework. A workbook containing literacy tasks was used to improve literacy skills of learners and was used as the instrument for the implementation of the teaching framework. The empirical study being reported here was aimed at determining to which degree the use of the workbook that had been developed as the instrument for the integration of the teaching framework, contributed to the improvement of the learners’ literacy skills. During the qualitative study, it was revealed that the teachers at the schools participating in this study were very positive about the workbook, and also that they were of the opinion that it could contribute to the improvement of the literacy skills of the learners. A practical significant influence with a large effect regarding general literacy and a small effect on general numeracy were reported. The analysis of the quantitative data showed that completion of the learning tasks in the workbook does indeed have an influence on improving the literacy level of the learners, and it is thus recommended that literacy skills be integrated into the existing CAT learning programme. / PhD (Teaching and Learning), North-West University, Potchefstroom Campus, 2012
19

Responsible use of social media by undergraduate student nurses / Ingrid van der Walt

Van der Walt, Ingrid January 2014 (has links)
The background and problem statement centre on the evolution of technology within teaching and learning, which involves undergraduate student nurses, as well as the use of social media as interactive teaching and communication tool. While examining the background to this topic, the researcher recognised a need to gain a deeper understanding of responsible social media use by undergraduate student nurses to the benefit of all the stakeholders, namely the Nursing Education Institution (NEI), applicable health care facilities, the patients and the student nurses. The study starts off with a literature review to peruse what is known about social media and information communication technology by undergraduate student nurses within a Higher Education (HE) environment. Literature shows that nurses in their work environment are not excluded from social media interaction processes. Within this context, social media offers improved contact and communication in general and in the working environment through the internet. The aim of this study is to explore and describe responsible use of social media by undergraduate student nurses. Methodology: The study followed a qualitative, explorative, descriptive and contextual design. All-inclusive, probable and purposive sampling (Brink, van der Walt & van Rensburg, 2006:134) was applied to select participants from a population of undergraduate student nurses (N=200, n=39). Prospective participants were informed by the researcher regarding the research by means of a Power Point slideshow and from there prospective participants had to make an informed decision to participate voluntarily in the research. Data was collected by means of an unstructured conversation between the researcher and participants via the real-time, online Chat Room of Sakai 2.9.1. Sakai 2.9.1 refers to an educational software platform which is a Java-based, service-oriented application used in an open source academic community. Sakai 2.9.1 is used within this context as a Course Management System and Virtual Learning Environment. The following questions were asked: “Tell me how you use your social media (e.g. Facebook™, Twitter™, WAYN™, LinkedIn™, WhatsApp™, etc.)”; “How do you access and on which device do you use social media?”, “What is your view of responsible social media use as a student nurse?” Although it was an all-inclusive sample and all members of the population were invited to participate, the sample size was established once the research reached data saturation (Brink et al., 2006:135). Thirty-nine participants (n=39) participated and the analysed results were first confirmed in a focus group. Six (6) main themes where identified, namely: social media as a quick academic reference; the social communication uses of social media; social curiosity; multiple social media registrations, but limited social media use; student nurses’ need for guidelines regarding responsible social media use and a need to share photographs on social media. The final conclusion was that student nurses entered the nursing profession with established social media skill. Yet, student nurses need guidance to divert social media use from a social perspective to social media use within a professional capacity. Recommendations for enhanced responsible social media use by student nurses where formulated. (Word count: 489) / MCur, North-West University, Potchefstroom Campus, 2014
20

The effect of Pheroid™ technology on the bioavailability of quinoline-based anti-malarial compounds in primates

Gibhard, Liezl January 2012 (has links)
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. However, the effect was reversed in MIM. Pheroid technology impacts differently on the bioavailability of the various pharmaceutical classes of anti-malarials. Pheroid technology did not enhance the bioavailability of amodiaquine or N-desethylamodiaquine. This is contrary to the observed effects of pheroid technology on the pharmacokinetics of other drugs such as artemisone and chloroquine where it increases the area under the curve and prolongs the drug half-life. / Thesis (PhD (Pharmaceutics))--North-West University, Potchefstroom Campus, 2013.

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