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Kreativitet är ett vanligt förekommande begrepp idag, både inom skola och näringsliv. Iläroplanen för grundskolan, förskoleklassen och fritidshemmet (Lgr 11) förekommer det påflertalet ställen men ingenstans definieras begreppet, varför tolkningen av densamma riskerarblir individuell.Min studie har för avsikt att skapa en ökad förståelse för begreppet kreativitet sett ur skolans,men även ur näringslivets perspektiv samt bena ut vad som anses främja kreativiteten.Studien består av en begreppsanalys där litteraturstudier samt insamlandet av empiri form avkvalitativa intervjuer ligger till grund för resultatet. Totalt sex intervjuer har genomförts varavtre med slöjdlärare och tre med företagare.Att entydigt definiera kreativitetsbegreppet har visat sig vara svårt men att det handlar om enprocess kring en ny och i förlängningen användbar idé framkommer i flera fall. Erfarenhetoch kunskap ses som mycket avgörande i den kreativa processen där dessa två parametraranvänds för att generera något nytt. Kreativitet kräver bland annat mod och självförtroendeför att våga pröva lösningar och idéer, men även god vägledning och coachning underprocessen visar sig gynna kreativiteten.Skolans syn på vad kreativitet är formuleras med betydligt fler ord än företagarnas. Detta kanses som ett bevis på att avsaknaden av en gemensam definition av begreppet riskerarelevernas utbildning då lärarens subjektiva tolkning av begreppet avgör hur kreativitet lärs ut.

Syftet med studien är att undersöka hur lärare i ämnet idrott och hälsa realiserar och transformerar de förmågor eleverna genom undervisningen syftar att utveckla samt vad införandet av ett centralt innehåll inneburit för dem i yrket. Till detta finns tre frågeställningar; hur tolkar lärare i idrott och hälsa ämnet idrott och hälsas förmågor i Lgr 11, hur undervisar lärare i idrott och hälsa utifrån ämnet idrott och hälsas förmågor i Lgr 11 och hur uppfattar lärare i idrott och hälsa ämnet idrott och hälsas centrala innehåll i Lgr 11. Som metod har intervjuer använts. Resultaten visar att lärare i ämnet idrott och hälsa tolkar och undervisar utifrån ämnets förmågor på olika sätt. Gällande det centrala innehållet så har det bland flertalet lärare inneburit struktur och tydlighet och i enstaka fall inget nytt. Slutsatsen av undersökningen är således att de förmågor som formuleras i ämnet idrott och hälsa transformeras och realiseras på olika sätt och att det centrala innehållet tillfört tydlighet och struktur i vissa fall och i andra fall inte.

Detta arbete syftar till att undersöka hur fyra F-3 lärare realiserar kursplanens centrala innehåll i religionskunskapsundervisning och vilka svårigheter och möjligheter lärare upplever med att undervisa i ämnet. Med hjälp av en kvalitativ metod har lärare intervjuats och ett resultat presenterats. I resultatet framkommer det att religionskunskapsundervisning ökar elevernas förståelse för varandra. Dock kan svårigheter uppstå i extremfall gällande föräldrar och vårdnadshavares åsikt om huruvida religion ska undervisas eller inte. Trots att lärare upplever svårigheter med att undervisa i religion, går det ofta att vända dessa till något positivt, vilket anges i vår slutsats.

Syftet med studien är att undersöka hur lärare, speciallärare och specialpedagoger arbetar i ämnet svenska med elever som har diagnosen dyslexi. Den teorin som arbetet grundar sig på är The Simple View of Reading, The Simple View of Writing och specialpedagogiska perspektiv vilka förklarar svårigheterna med diagnosen dyslexi samt vad eleverna behöver hjälp med. Genom att använda en kvalitativ forskningsansats och då i form av intervjuer, semistrukturerade intervjuer, har en djupare förståelse för undervisningsmetoder, anpassningar och former av särskilt stöd och hur de används i praktiken erhållits. De personer som har intervjuats är svensklärare, speciallärare och specialpedagoger och samtliga av de 12 respondenterna är verksamma inom årskurserna 6-9. Resultatet av studien visade att elever med dyslexi måste få hjälp i tid för att inte en större problematik ska uppstå och att de inte hamnar mer efter. Intervjuerna visade också en skillnad i hur insatta olika lärare är i diagnosen dyslexi och digitala verktyg som hjälpmedel, även en skillnad mellan svensklärare och speciallärare och specialpedagoger tydliggjordes. De sistnämnda ansåg sig mer kompetenta inom ämnet. Vidare används digitala verktyg i undervisningen, detta trots att kunskapen om digitala verktyg också den varierade bland de intervjuade pedagogerna. Slutligen kan nämnas att tidsbrist var en faktor som påverkade undervisningen, en elev med dyslexi behöver mer tid för att exempelvis färdigställa en uppgift eller då eleven har prov kan det delas upp i flera delar som görs vid olika tillfällen.    Nyckelord: anpassningar, digitala verktyg, dyslexi, kvalitativ forskningsansats och samarbete

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used in the treatment of inflammation and pain (Escribano et al., 2003:203). Diclofenac, a classical NSAID, is considerably more effective as an analgesic, antipyretic and anti-inflammatory drug than other traditional NSAIDs, like indomethacin and naproxen (Grosser et al., 2011:986). However, the use of diclofenac is known for its many side effects, such as gastric disorders, while fluid and sodium retention are also commonly observed (Rossiter, 2012:391). Since topical diclofenac offers a more favourable safety profile, it is a valuable substitute for oral NSAID therapy in the treatment of osteoarthritis (Roth & Fuller, 2011:166). The benefits of topically applied NSAIDs, compared to oral administration and systemic delivery, include the easy cessation of treatment, should effects become troublesome (Brown et al., 2006:177), the avoidance of extensive, first-pass metabolism (Cleary, 1993:19; Kornick, 2003:953; Prausnitz & Langer, 2008:1261; Lionberger & Brennan, 2010:225), reduced systemic side effects (Colin Long, 2002:41), convenience of application and improved patient compliance (Cleary, 1993:19; Prausnitz & Langer, 2008:1261). An approach that is often applied in optimising the solubility and dissolution rate of poorly water soluble, weak electrolytes is to prepare a salt of the active pharmaceutical ingredient (API) (Minghetti et al., 2007:815; O’Connor & Corrigan, 2001:281-282). Diclofenac is frequently administered as a salt, due to the high partition coefficient and very low water solubility of this molecule (Fini et al., 1999:164). Formulating for efficacy (FFETM) is a software programme designed by JW Solutions to facilitate the formulation of cosmetic ingredients or solvents into a product that would optimally deliver active ingredients into the skin. The notion is built upon solubility, i.e. solubility of the active ingredient in the formulation and solubility of the formulation in the skin. This programme could also be employed to optimise amounts of predetermined ingredients, to propose formulations that would ensure optimal drug delivery, to calculate the skin delivery gap (SDG) and to demonstrate transdermal permeation of active ingredients and excipients (JW Solutions Software, 2013a). When the SDG is known, it mathematically indicates the optimal active ingredient and topical delivery vehicle to use (JW Solutions, 2013b). In this study, diclofenac sodium (DNa), diclofenac diethylamine (DDEA) and diclofenac N-(2- hydroxyethyl) pyrrolidine (DHEP) were each formulated in the following emulgels: * An emulgel optimised towards the stratum corneum (SC) (enhancing drug delivery into this layer and deeper tissues) (oily phase ~30%), * A more hydrophilic emulgel (oily phase ~15%), and * A more lipophilic emulgel (oily phase ~45%). Components of the oily phase and its respective amounts, as well as the SDG of formulations were determined by utilising the FFETM software of JW Solutions (2013a). The aqueous solubilities of DNa, DDEA and DHEP were determined and their respective values were 11.4 mg/ml, 8.0 mg/ml and 11.9 mg/ml, all indicative of effortless percutaneous delivery (Naik et al., 2000:319). Log D (octanol-buffer distribution coefficient) (pH 7.4) determinations for DNa, DDEA and DHEP were performed and their values established at 1.270 (DNa), 1.291 (DDEA) and 1.285 (DHEP). According to these values, diclofenac, when topically applied as a salt in a suitable vehicle, should permeate transdermally without the aid of radical intervention (Naik et al., 2000:319; Walters, 2007:1312). Membrane release studies were also carried out in order to determine the rate of API release from these new formulations. Results confirmed that diclofenac was indeed released from all nine of the formulated emulgels. The more hydrophilic DNa formulation released the highest average percentage of diclofenac (8.38%) after 6 hours. Subsequent transdermal diffusion studies were performed to determine the diclofenac concentration that permeated the skin. The more hydrophilic DNa emulgel showed the highest average percentage skin diffusion (0.09%) after 12 hours, as well as the highest average flux (1.42 ± 0.20 μg/cm2.h). The concentrations of diclofenac in the SC-epidermis (SCE) and epidermis-dermis (ED) were determined through tape stripping experiments. The more lipophilic DNa emulgel demonstrated the highest average concentration (0.27 μg/ml) in the ED, while the DNa emulgel that had been optimised towards the SC, had the highest concentration in the SCE (0.77 μg/ml). / MSc (Pharmaceutics), North-West University, Potchefstroom Campus, 2014

Nonsteroidal anti-inflammatory drugs (NSAIDs) are widely used in the treatment of inflammation and pain (Escribano et al., 2003:203). Diclofenac, a classical NSAID, is considerably more effective as an analgesic, antipyretic and anti-inflammatory drug than other traditional NSAIDs, like indomethacin and naproxen (Grosser et al., 2011:986). However, the use of diclofenac is known for its many side effects, such as gastric disorders, while fluid and sodium retention are also commonly observed (Rossiter, 2012:391). Since topical diclofenac offers a more favourable safety profile, it is a valuable substitute for oral NSAID therapy in the treatment of osteoarthritis (Roth & Fuller, 2011:166). The benefits of topically applied NSAIDs, compared to oral administration and systemic delivery, include the easy cessation of treatment, should effects become troublesome (Brown et al., 2006:177), the avoidance of extensive, first-pass metabolism (Cleary, 1993:19; Kornick, 2003:953; Prausnitz & Langer, 2008:1261; Lionberger & Brennan, 2010:225), reduced systemic side effects (Colin Long, 2002:41), convenience of application and improved patient compliance (Cleary, 1993:19; Prausnitz & Langer, 2008:1261). An approach that is often applied in optimising the solubility and dissolution rate of poorly water soluble, weak electrolytes is to prepare a salt of the active pharmaceutical ingredient (API) (Minghetti et al., 2007:815; O’Connor & Corrigan, 2001:281-282). Diclofenac is frequently administered as a salt, due to the high partition coefficient and very low water solubility of this molecule (Fini et al., 1999:164). Formulating for efficacy (FFETM) is a software programme designed by JW Solutions to facilitate the formulation of cosmetic ingredients or solvents into a product that would optimally deliver active ingredients into the skin. The notion is built upon solubility, i.e. solubility of the active ingredient in the formulation and solubility of the formulation in the skin. This programme could also be employed to optimise amounts of predetermined ingredients, to propose formulations that would ensure optimal drug delivery, to calculate the skin delivery gap (SDG) and to demonstrate transdermal permeation of active ingredients and excipients (JW Solutions Software, 2013a). When the SDG is known, it mathematically indicates the optimal active ingredient and topical delivery vehicle to use (JW Solutions, 2013b). In this study, diclofenac sodium (DNa), diclofenac diethylamine (DDEA) and diclofenac N-(2- hydroxyethyl) pyrrolidine (DHEP) were each formulated in the following emulgels: * An emulgel optimised towards the stratum corneum (SC) (enhancing drug delivery into this layer and deeper tissues) (oily phase ~30%), * A more hydrophilic emulgel (oily phase ~15%), and * A more lipophilic emulgel (oily phase ~45%). Components of the oily phase and its respective amounts, as well as the SDG of formulations were determined by utilising the FFETM software of JW Solutions (2013a). The aqueous solubilities of DNa, DDEA and DHEP were determined and their respective values were 11.4 mg/ml, 8.0 mg/ml and 11.9 mg/ml, all indicative of effortless percutaneous delivery (Naik et al., 2000:319). Log D (octanol-buffer distribution coefficient) (pH 7.4) determinations for DNa, DDEA and DHEP were performed and their values established at 1.270 (DNa), 1.291 (DDEA) and 1.285 (DHEP). According to these values, diclofenac, when topically applied as a salt in a suitable vehicle, should permeate transdermally without the aid of radical intervention (Naik et al., 2000:319; Walters, 2007:1312). Membrane release studies were also carried out in order to determine the rate of API release from these new formulations. Results confirmed that diclofenac was indeed released from all nine of the formulated emulgels. The more hydrophilic DNa formulation released the highest average percentage of diclofenac (8.38%) after 6 hours. Subsequent transdermal diffusion studies were performed to determine the diclofenac concentration that permeated the skin. The more hydrophilic DNa emulgel showed the highest average percentage skin diffusion (0.09%) after 12 hours, as well as the highest average flux (1.42 ± 0.20 μg/cm2.h). The concentrations of diclofenac in the SC-epidermis (SCE) and epidermis-dermis (ED) were determined through tape stripping experiments. The more lipophilic DNa emulgel demonstrated the highest average concentration (0.27 μg/ml) in the ED, while the DNa emulgel that had been optimised towards the SC, had the highest concentration in the SCE (0.77 μg/ml). / MSc (Pharmaceutics), North-West University, Potchefstroom Campus, 2014

Acne vulgaris is the single, most common disease that presents a significant challenge to dermatologists, due to its complexity, prevalence and range of clinical expressions. This condition can be found in 85% of teenage boys and 80% of girls (Gollnick, 2003:1580). Acne can cause serious psychological consequences (low self–esteem, social inhibition, depression, etc.), if left untreated, and should therefore be recognised as a serious disorder (Webster, 2001:15). The pathogenesis of acne is varied, with factors that include plugging of the follicle, accumulation of sebum, growth of Propionibacterium acnes (P. acnes), and inflammatory tissue responses (Wyatt et al., 2001:1809). Acne treatment focuses on the reduction of inflammatory and non–inflammatory acne lesions, and thus halts the scarring process (Railan & Alster, 2008:285). Non–inflammatory acne lesions can be expressed as open and closed comedones, whereas inflammatory lesions comprise of papules, pustules, nodules and cysts (Gollnick, 2003:1581). Acne treatment may be topical, or oral. Topical treatment is the most suitable first–line therapy for non–inflammatory comedones, or mildly inflammatory disease states, with the advantage of avoiding the possible systemic effects of oral medications (Federman & Kirsner, 2000:80). Topical retinoids were very successfully used for the treatment of acne in the 1980s. Their effectiveness in long–term therapies was limited though, due to local skin irritations that occurred in some individuals (Julie & Harper, 2004:S36). Vitamin A acetate presented a new approach in the treatment of acne, showing less side effects (Cheng & Depetris, 1998:7). In this study, vitamin A acetate and zinc acetate were formulated into semisolid, combination formulations for the possible treatment of acne. Whilst vitamin A controls the development of microcomedones, reduces existing comedones, diminishes sebum production and moderately reduces inflammation (Verschoore et al., 1993:107), zinc normalises hormone imbalances (Nutritional–supplements–health–guide.com, 2005:2) and normalises the secretion of sebum (Hostýnek & Maibach, 2002:35). Although the skin presents many advantages to the delivery of drugs, it unfortunately has some limitations. The biggest challenge in the transdermal delivery of drugs is to overcome the natural skin barrier. Its physicochemical properties are a good indication(s) of the transdermal behaviour of a drug. The ideal drug to be used in transdermal delivery would have sufficient lipophilic properties to partition into the stratum corneum, but it would also have sufficient hydrophilic properties to partition into the underlying layers of the skin (Kalia & Guy, 2001:159). Pheroid technology was also implemented during this study, in order to establish whether it would enhance penetration of the active ingredients across the skin. The Pheroid consists of vesicular structures that contain no phospholipids, nor cholesterol, but consists of the same essential fatty acids that are present in humans (Grobler et al., 2008:283). The aim of this study hence was to investigate the transdermal delivery of vitamin A acetate and zinc acetate, jointly formulated into four topical formulations for acne treatment. Vitamin A acetate (0.5%) and zinc acetate (1.2%) were formulated into a cream, Pheroid cream, emulgel and Pheroid emulgel. An existing commercial product, containing vitamin A acetate, was used to compare the results of the formulated products with. The transdermal, epidermal and dermal diffusion of the formulations were determined during a 6 h diffusion study, using Franz diffusion cells and tape stripping techniques. Experimental determination of the diffusion studies proved that vitamin A acetate did not penetrate through the skin. These results applied to both the formulations being developed during this study, as well as to the commercial product. Tape stripping studies were done to determine the concentration of drug present in the epidermis and dermis. The highest epidermal concentration of vitamin A acetate was obtained with the Pheroid emulgel (0.0045 ug/ml), whilst the emulgel formulation provided the highest vitamin A acetate concentration in the dermis (0.0029 ug/ml). Contrary, for the commercial product, the total concentration of vitamin A acetate in the epidermis was noticeably lower than for all the new formulations studied. Vitamin A acetate concentrations of the commercial product in the dermis were within the same concentration range as the newly developed formulations, with the exception of the emulgel that delivered approximately 31% more vitamin A acetate to the dermis, than the commercial product. Zinc acetate was able to diffuse through full thickness skin, although no flux values were obtained. To eliminate the possibility of endogenous zinc diffusion, placebo formulations (without zinc) were prepared for use as control samples during the skin diffusion investigation. The emulgel and Pheroid emulgel formulations were unable to deliver significant zinc acetate concentrations transdermally, although transdermal diffusion was attained from both the cream and Pheroid cream. Tape stripping experiments with placebo formulations relative to the formulated products revealed that zinc acetate concentrations in the epidermis and dermis were significantly higher when the placebo formulations were applied. However, the average zinc acetate concentration in the dermis, after application of the cream formulation, was significantly higher, compared to when the placebo cream was applied. It could therefore be concluded that no zinc acetate had diffused into the epidermis and dermis from the new formulations, except from the cream formulation. The zinc acetate concentration being measured in the epidermis thus rather represented the endogenous zinc acetate. The cream formulation, however, was probably able to deliver detectable zinc acetate concentrations to the epidermis. Stability of the formulated products was tested under a variety of environmental conditions to determine whether the functional qualities would remain within acceptable limits over a certain period of time. The formulated products were tested for a period of three months under storage conditions of 25°C/60% RH (relative humidity), 30°C/60% RH and 40°C/75% RH. Stability studies included stability indicating assay testing, the determination of rheology, pH, droplet size, zeta–potential, mass loss, morphology of the particles and physical assessment. The formulations were unstable over the three months stability test period. A change in viscosity, colour and concentration of the active ingredients were observed. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2011.

Non–melanoma skin cancer (NMSC) is the most common human malignancy and it is estimated that over 1.3 million cases are diagnosed each year in the United States (Neville et al., 2007:462). There are three main types of NMSC, which include basal–cell carcinoma (BCC), squamous–cell carcinoma (SCC) and cutaneous malignant melanoma (CMM). Exposure to ultra–violet (UV) radiation plays a major role in the aetiology of these three skin cancer types (Franceschi et al., 1996:24). 5–Fluorouracil is an antineoplastic pyrimidine analogue that functions as an anti–metabolite. It interferes with DNA (deoxyribonucleic acid), and to a lesser extent, with RNA (ribonucleic acid) synthesis by blocking the methylation of deoxyuridylic acid into thymidylic acid. It is used in topical preparations for the treatment of actinic keratosis (AK) and NMSC. The cure rate with topical 5–fluorouracil is partly reflected by the degree of erythema, erosions, and eventual crusting which develop at the sites of treatment. This reaction often attains the best clinical response, but in turn, frustrates patients, which may lead to patient incompliance (McGillis & Fein, 2004:175). Due to the hydrophilic nature of 5–fluorouracil, the transdermal permeation through the lipophilic stratum corneum is very low and trivial (Singh et al., 2005:99). Transdermal drug delivery is the delivery of a chemical substance across the skin to reach the systemic circulation (Prausnitz et al., 2004:115). This unique drug transport mechanism suggests many advantages that include safety, patient compliance, user–friendliness, efficiency and non–invasiveness (Fang et al., 2004:241). The stratum corneum is a specialised structure that forms part of several anatomically distinct layers of the skin. Seeing that it is the outermost layer, it provides protection to the skin. It is known as the main barrier to percutaneous absorption of compounds, as well as water loss, through the skin (Bouwstra et al., 2003:4). This study focussed on the formulation of six different types of semisolid formulations, containing 0.5% 5–fluorouracil. The formulations included: a cream, Pheroid cream, emulgel, Pheroid emulgel, lotion and Pheroid lotion. Pheroid refers to a delivery system which was incorporated in the formulations in an attempt to enhance the penetration of 5–fluorouracil into the skin. This drug delivery system consists of unique and stable lipid–based submicronand micron–sized structures, formulated in an emulsion. The dispersed Pheroid structures largely comprise of natural essential fatty acids, which have an affinity for the cell membranes of the human body (Grobler et al., 2008:284–285). These formulations were manufactured in large quantities and stored at three different temperatures, each with their respective relative humidity (RH): 25 °C/60% RH, 30 °C/60% RH and 40 °C/70% RH, for a period of six months. Stability tests were conducted on each of these formulations on the day of manufacture (month 0), and then after 1, 2, 3 and 6 months. The tests included: determination of concentration of the analytes (assay) by means of high performance liquid chromatography (HPLC); determination of zeta–potential and droplet size; pH measurement; viscosity; mass loss determination; physical appearance; and particle size distribution. Franz cell skin diffusion tests were performed with these six 5–fluorouracil containing semisolid formulations (0.5%), as well as with a 0.5% Pheroid solution, 0.5% non–Pheroid solution. A 5.0% Pheroid solution and a 5.0% non–Pheroid solution were also prepared in order to compare the skin diffusion test results to a 5.0% commercially available ointment. The data of the 0.5% formulations and solutions, as well as the 5.0% solutions and commercial ointment, were statistically compared and those formulations (and solutions) that yielded the best results, with regard to % diffused, epidermis and dermis concentrations, were identified. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2011.

Acne vulgaris is the single, most common disease that presents a significant challenge to dermatologists, due to its complexity, prevalence and range of clinical expressions. This condition can be found in 85% of teenage boys and 80% of girls (Gollnick, 2003:1580). Acne can cause serious psychological consequences (low self–esteem, social inhibition, depression, etc.), if left untreated, and should therefore be recognised as a serious disorder (Webster, 2001:15). The pathogenesis of acne is varied, with factors that include plugging of the follicle, accumulation of sebum, growth of Propionibacterium acnes (P. acnes), and inflammatory tissue responses (Wyatt et al., 2001:1809). Acne treatment focuses on the reduction of inflammatory and non–inflammatory acne lesions, and thus halts the scarring process (Railan & Alster, 2008:285). Non–inflammatory acne lesions can be expressed as open and closed comedones, whereas inflammatory lesions comprise of papules, pustules, nodules and cysts (Gollnick, 2003:1581). Acne treatment may be topical, or oral. Topical treatment is the most suitable first–line therapy for non–inflammatory comedones, or mildly inflammatory disease states, with the advantage of avoiding the possible systemic effects of oral medications (Federman & Kirsner, 2000:80). Topical retinoids were very successfully used for the treatment of acne in the 1980s. Their effectiveness in long–term therapies was limited though, due to local skin irritations that occurred in some individuals (Julie & Harper, 2004:S36). Vitamin A acetate presented a new approach in the treatment of acne, showing less side effects (Cheng & Depetris, 1998:7). In this study, vitamin A acetate and zinc acetate were formulated into semisolid, combination formulations for the possible treatment of acne. Whilst vitamin A controls the development of microcomedones, reduces existing comedones, diminishes sebum production and moderately reduces inflammation (Verschoore et al., 1993:107), zinc normalises hormone imbalances (Nutritional–supplements–health–guide.com, 2005:2) and normalises the secretion of sebum (Hostýnek & Maibach, 2002:35). Although the skin presents many advantages to the delivery of drugs, it unfortunately has some limitations. The biggest challenge in the transdermal delivery of drugs is to overcome the natural skin barrier. Its physicochemical properties are a good indication(s) of the transdermal behaviour of a drug. The ideal drug to be used in transdermal delivery would have sufficient lipophilic properties to partition into the stratum corneum, but it would also have sufficient hydrophilic properties to partition into the underlying layers of the skin (Kalia & Guy, 2001:159). Pheroid technology was also implemented during this study, in order to establish whether it would enhance penetration of the active ingredients across the skin. The Pheroid consists of vesicular structures that contain no phospholipids, nor cholesterol, but consists of the same essential fatty acids that are present in humans (Grobler et al., 2008:283). The aim of this study hence was to investigate the transdermal delivery of vitamin A acetate and zinc acetate, jointly formulated into four topical formulations for acne treatment. Vitamin A acetate (0.5%) and zinc acetate (1.2%) were formulated into a cream, Pheroid cream, emulgel and Pheroid emulgel. An existing commercial product, containing vitamin A acetate, was used to compare the results of the formulated products with. The transdermal, epidermal and dermal diffusion of the formulations were determined during a 6 h diffusion study, using Franz diffusion cells and tape stripping techniques. Experimental determination of the diffusion studies proved that vitamin A acetate did not penetrate through the skin. These results applied to both the formulations being developed during this study, as well as to the commercial product. Tape stripping studies were done to determine the concentration of drug present in the epidermis and dermis. The highest epidermal concentration of vitamin A acetate was obtained with the Pheroid emulgel (0.0045 ug/ml), whilst the emulgel formulation provided the highest vitamin A acetate concentration in the dermis (0.0029 ug/ml). Contrary, for the commercial product, the total concentration of vitamin A acetate in the epidermis was noticeably lower than for all the new formulations studied. Vitamin A acetate concentrations of the commercial product in the dermis were within the same concentration range as the newly developed formulations, with the exception of the emulgel that delivered approximately 31% more vitamin A acetate to the dermis, than the commercial product. Zinc acetate was able to diffuse through full thickness skin, although no flux values were obtained. To eliminate the possibility of endogenous zinc diffusion, placebo formulations (without zinc) were prepared for use as control samples during the skin diffusion investigation. The emulgel and Pheroid emulgel formulations were unable to deliver significant zinc acetate concentrations transdermally, although transdermal diffusion was attained from both the cream and Pheroid cream. Tape stripping experiments with placebo formulations relative to the formulated products revealed that zinc acetate concentrations in the epidermis and dermis were significantly higher when the placebo formulations were applied. However, the average zinc acetate concentration in the dermis, after application of the cream formulation, was significantly higher, compared to when the placebo cream was applied. It could therefore be concluded that no zinc acetate had diffused into the epidermis and dermis from the new formulations, except from the cream formulation. The zinc acetate concentration being measured in the epidermis thus rather represented the endogenous zinc acetate. The cream formulation, however, was probably able to deliver detectable zinc acetate concentrations to the epidermis. Stability of the formulated products was tested under a variety of environmental conditions to determine whether the functional qualities would remain within acceptable limits over a certain period of time. The formulated products were tested for a period of three months under storage conditions of 25°C/60% RH (relative humidity), 30°C/60% RH and 40°C/75% RH. Stability studies included stability indicating assay testing, the determination of rheology, pH, droplet size, zeta–potential, mass loss, morphology of the particles and physical assessment. The formulations were unstable over the three months stability test period. A change in viscosity, colour and concentration of the active ingredients were observed. / Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2011.