A cana-de-açúcar é um alimento bem aceito por toda a população em geral, podendo ser consumido na forma de toletes (in natura) ou na forma de caldo, podendo ser apreciado com gelo somente, ou adicionado de sucos cítricos, mas nem sempre tratada com algum sanitizante ou outro produto para manutenção de sua qualidade. A cana-de-açúcar também pode ser consumida na forma de minimamente processada, sanitizada e embalada, facilitando sua utilização em redes de alimentação. Embora o processamento mínimo de vegetais aumente a suscetibilidade ao ataque de microrganismos e escurecimento enzimático, essas alterações podem ser reduzidas com o uso de tratamentos adequados, como sanitizantes e agentes antioxidantes. Em vista disso, procurou-se nesse trabalho avaliar a qualidade da cana-de-açúcar minimamente processada, tratada com antioxidantes e radiação gama. Os tratamentos aplicados para a conservação dos toletes de cana-de-açúcar foram: ácido cítrico nas concentrações de 1,5% e 3,0%; cloridato de L-cisteína a 1,0% e 2,0%; radiação gama com as doses de 2,0 e 4,0 kGy. Antes de receberem os tratamentos, os toletes de cana-de-açúcar foram processados e sanitizados com solução de hipoclorito de sódio. Após a drenagem, os toletes foram acondicionados em embalagens de polietileno de alta densidade e refrigerados a 4°C. Os produtos foram analisados após 1, 7 e 14 dias de armazenamento. Todos os tratamentos apresentaram-se em condições sanitárias adequadas para o consumo, independente das concentrações e dosagens. Os toletes de canas-de-açúcar tratados com ácido cítrico e cloridrato de L-cisteína apresentaram os melhores resultados quanto à inibição das enzimas de escurecimento, polifenoloxidase e peroxidase, sendo a cana-de-açúcar tratada com L-cisteína a que apresentou o caldo com melhores resultados quanto à inibição de seu escurecimento e níveis de açúcares. Todos os tratamentos inibiram o desenvolvimento de microrganismos / Sugar cane is a well-accepted food for the general population and can be consumed in the form of straw (in natura) or in the form of juice, which can be enjoyed with ice only, or added with citrus juice, but always treated with some sanitizing agent or other product to maintain its quality. Sugarcane can also be consumed in the form of minimally processed, sanitized and packaged sugarcane, improving its use in food networks. Unless, minimal processing of vegetables increases susceptibility to microorganism attack and enzymatic browning, but such changes can be reduced with the use of appropriate treatments such as sanitizers and antioxidants. The aim of this work was to evaluate the quality of minimally processed sugar cane treated with antioxidants or gamma radiation. The treatments applied for the preservation of sugarcane straw were: citric acid at concentrations of 1.5% and 3.0%; L-cysteine at concentrations of 1.0% and 2.0%, and gamma irradiation at doses of 2.0 and 4.0 kGy. Before receiving the treatments, the sugar cane straws were processed and sanitized with sodium hypochlorite solution. After draining, the straws were packed in high-density polyethylene packages and refrigerated at 4°C. The products were analyzed after 1, 7 and 14 days of storage. All treatments were in sanitary conditions suitable for the consumption, independent of the concentrations and dosages. The sugarcane treated with citric acid and L-cysteine presented the best results regarding the inhibition of the darkening enzymes, polyphenoloxidase and peroxidase. Sugarcane treated with L-cysteine presented the juice with better sugar levels and inhibition of browning. All treatments showed effective inhibiton of the microorganisms development

O uso acentuado de fármacos e de produtos de higiene e cuidados pessoais por grande parcela da população e a conseqüente e contínua entrada dos mesmos no ambiente gera uma necessidade cada vez maior de se investigar a presença, o comportamento e os efeitos causados à biota aquática, bem como novas formas de tratamento para efluentes contendo tais substâncias. O cloridrato de fluoxetina é um princípio ativo utilizado em tratamentos de distúrbios depressivos e de ansiedade. Enquanto o surfactante dodecilsulfato de sódio está presente em diversos produtos de limpeza e de cuidados pessoais. O presente estudo teve como enfoque avaliar a toxicidade aguda do cloridrato de fluoxetina, dodecil sulfato de sódio bem como a mistura de ambos frente aos organismos aquáticos Hyalella azteca, Daphnia similis e Vibrio ficheri. A redução da toxicidade do cloridrato de fluoxetina e da mistura após tratamento com radiação ionizante, proveniente de acelerador industrial de elétrons, também foi objeto de estudo. Para Daphnia similis os valores médios de CE5048h encontrados para o fármaco, o surfactante e a mistura não irradiados foram de 14,4 %, 9,62% e 13,8%, respectivamente. Após irradiação das substâncias, a dose de 5 kGy se mostrou a mais efetiva, resultando em valores médios de CE5048h de 84,60% e >90 %, para o fármaco e para a mistura respectivamente. Para Hyalella azteca foram realizados ensaios de toxicidade aguda para coluna d\'água com duração de 96 horas, cujas médias dos valores de CE5096h encontradas para o fármaco, o surfactante e a mistura não irradiados foram de 5,63 %, 19,29 %, 6,27 %, respectivamente. Para o fármaco e mistura irradiados com a dose de 5 kGy, foram de 69,57% e 77,7 %, respectivamente. Para Vibrio ficheri os ensaios de toxicidade aguda para o fármaco não tratado e para o fármaco irradiado com 5 kGy geraram valores de CE5015min de 6,9 % e 32,88 %, respectivamente. Tais resultados evidenciaram a redução da toxicidade das subtâncias - teste após irradiação. / The use of pharmaceuticals and personal care products and the consequent and continuous input of this substances in the environment generates an increasing need to investigate the presence, behavior and the effects on aquatic biota, as well as new ways to treat effluents containing such substances. Fluoxetine hydrochloride is an active ingredient used in the treatment of depressive disorders and anxiety. As the surfactant sodium dodecyl sulfate is present in many cleaning and personal care products. The present study aimed on assessing the acute toxicity of fluoxetine hydrochloride, sodium dodecyl sulfate and the mixture of both to the aquatic organisms Hyalella azteca, Daphnia similis and Vibrio ficheri. Reducing the toxicity of fluoxetine and the mixture after treatment with ionizing radiation from industrial electron beam accelerator has also been the focus of this study. For Daphnia similis the average values of CE5048h found for the non-irradiated drug, surfactant and mixture were 14.4 %, 9.62 % and 13.8 %, respectively. After irradiation of the substances, the dose 5 kGy proved itself to be the most effective dose for the treatmet of the drug and the mixture as it was obtained the mean values for CE5048h 84.60 % and > 90 %, respectively. For Hyalella azteca the acute toxicity tests were performed for water column with duration of 96 hours, the mean values for CE5096h found for the drug, the surfactant and the mixture non-irradiated were 5.63 %, 19.29 %, 6.27 %, respectively. For the drug fluoxetine and the mixture irradiated with 5 kGy, it was obtained 69.57 % and 77.7 %, respectively. For Vibrio ficheri the acute toxicity tests for the untreated drug and the drug irradiated with 5 kGy it was obtained CE5015min of 6.9 % and 32.88 % respectively. These results presented a reduction of the acute toxicity of the test-substances after irradiation.

A presença de sais no petróleo ocasiona grandes problemas operacionais relacionados à corrosão, uma vez que estes acabam formando ácido clorídrico no processo de separação do óleo bruto. Com o intuito de amenizar os efeitos de corrosão ácida, aminas podem ser adicionadas no topo das colunas para agir como neutralizantes. Porém, dependendo das condições operacionais e da quantidade de amina adicionada, pode ocorrer a deposição de cloridratos de aminas, promovendo a corrosão sob depósito. Assim, o conhecimento da pressão de sublimação desses sólidos é de extrema importância para especificar as condições de operação e o melhor desempenho destes aditivos no processo. Dentro desse contexto, o objetivo deste trabalho é determinar as pressões e entalpias de sublimação de cloridratos de aminas com a técnica termogravimétrica. Devido às dificuldades encontradas para obtenção de dados precisos de pressão em baixas temperaturas, uma extensão ao método termogravimétrico foi proposta, tornando possível medir pressões na ordem de 1 0,5 Pa. As substâncias estudadas foram: brometo de amônio, cloreto de amônio, cloridrato de etanolamina, cloridrato de metilamina, cloridrato de piridina, cloridrato de trimetilamina e dicloridrato de n-(1- naftil)etilenodiamina. Resultados de pressão e entalpia de sublimação alcançados com ácido benzoico, brometo de amônio e cloreto de amônio foram validados com dados da literatura Para os demais sólidos estudados, não há muitos dados disponíveis na literatura. No entanto, como a reação de sublimação do cloreto de amônio é análoga à dos demais cloridratos de amina, as entalpias de sublimação puderam ser comparadas e os resultados encontrados foram satisfatórios. Por fim, para uma melhor aplicabilidade dos resultados obtidos, uma equação de Clausius-Clapeyron modificada foi utilizada para correlacionar os dados medidos. Uma ótima correlação foi possível para todos os sais estudados, com coeficiente de correlação sempre superior a 0,97. / The presence of salts in petroleum causes operational problems related to corrosion, due to the fact that they end up forming hydrochloric acid in the crude oil separation process. In order to mitigate the effects of acid corrosion, amines can be added at the top of the columns to act as neutralizers. However, depending on the operational conditions and the amount of amine added, a deposition of amine hydrochlorides may occur, promoting under-deposit corrosion. Thus, the knowledge of the sublimation pressure of these salts has an extreme importance in trying to predict and to optimize the performance of the additives in the process. Within this context, the purpose of this study is to determine pressure and enthalpy of sublimation of amine hydrochlorides with the thermogravimetric technique. Due to the difficulties encountered to obtain precise pressure data at low temperatures, an extension of the thermogravimetric method was proposed, enabling to measure sublimation pressures in the order of 1 0,5 Pa. The substances studied were: ammonium bromide, ammonium chloride, ethanolamine hydrochloride, methylamine hydrochloride, pyridine hydrochloride, trimethylamine hydrochloride and n-(1-naphthyl)ethylenediamine dihydrochloride. Results of pressure and enthalpy of sublimation obtained with benzoic acid, ammonium bromide and ammonium chloride were validated using literature data. For other solids investigated in this study, experimental data is scarce in the literature. However, as the sublimation reaction of ammonium chloride is analogous to the others amine hydrochlorides, enthalpies of sublimation could be compared with the results found. Since similar values were observed, the results were considered satisfactory. Finally, the measured data were correlated using a modified Clausius-Clapeyron equation. A good correlation was possible for all salts studied, with correlation coefficient always higher than 0.97.

O uso acentuado de fármacos e de produtos de higiene e cuidados pessoais por grande parcela da população e a conseqüente e contínua entrada dos mesmos no ambiente gera uma necessidade cada vez maior de se investigar a presença, o comportamento e os efeitos causados à biota aquática, bem como novas formas de tratamento para efluentes contendo tais substâncias. O cloridrato de fluoxetina é um princípio ativo utilizado em tratamentos de distúrbios depressivos e de ansiedade. Enquanto o surfactante dodecilsulfato de sódio está presente em diversos produtos de limpeza e de cuidados pessoais. O presente estudo teve como enfoque avaliar a toxicidade aguda do cloridrato de fluoxetina, dodecil sulfato de sódio bem como a mistura de ambos frente aos organismos aquáticos Hyalella azteca, Daphnia similis e Vibrio ficheri. A redução da toxicidade do cloridrato de fluoxetina e da mistura após tratamento com radiação ionizante, proveniente de acelerador industrial de elétrons, também foi objeto de estudo. Para Daphnia similis os valores médios de CE5048h encontrados para o fármaco, o surfactante e a mistura não irradiados foram de 14,4 %, 9,62% e 13,8%, respectivamente. Após irradiação das substâncias, a dose de 5 kGy se mostrou a mais efetiva, resultando em valores médios de CE5048h de 84,60% e >90 %, para o fármaco e para a mistura respectivamente. Para Hyalella azteca foram realizados ensaios de toxicidade aguda para coluna d\'água com duração de 96 horas, cujas médias dos valores de CE5096h encontradas para o fármaco, o surfactante e a mistura não irradiados foram de 5,63 %, 19,29 %, 6,27 %, respectivamente. Para o fármaco e mistura irradiados com a dose de 5 kGy, foram de 69,57% e 77,7 %, respectivamente. Para Vibrio ficheri os ensaios de toxicidade aguda para o fármaco não tratado e para o fármaco irradiado com 5 kGy geraram valores de CE5015min de 6,9 % e 32,88 %, respectivamente. Tais resultados evidenciaram a redução da toxicidade das subtâncias - teste após irradiação. / The use of pharmaceuticals and personal care products and the consequent and continuous input of this substances in the environment generates an increasing need to investigate the presence, behavior and the effects on aquatic biota, as well as new ways to treat effluents containing such substances. Fluoxetine hydrochloride is an active ingredient used in the treatment of depressive disorders and anxiety. As the surfactant sodium dodecyl sulfate is present in many cleaning and personal care products. The present study aimed on assessing the acute toxicity of fluoxetine hydrochloride, sodium dodecyl sulfate and the mixture of both to the aquatic organisms Hyalella azteca, Daphnia similis and Vibrio ficheri. Reducing the toxicity of fluoxetine and the mixture after treatment with ionizing radiation from industrial electron beam accelerator has also been the focus of this study. For Daphnia similis the average values of CE5048h found for the non-irradiated drug, surfactant and mixture were 14.4 %, 9.62 % and 13.8 %, respectively. After irradiation of the substances, the dose 5 kGy proved itself to be the most effective dose for the treatmet of the drug and the mixture as it was obtained the mean values for CE5048h 84.60 % and > 90 %, respectively. For Hyalella azteca the acute toxicity tests were performed for water column with duration of 96 hours, the mean values for CE5096h found for the drug, the surfactant and the mixture non-irradiated were 5.63 %, 19.29 %, 6.27 %, respectively. For the drug fluoxetine and the mixture irradiated with 5 kGy, it was obtained 69.57 % and 77.7 %, respectively. For Vibrio ficheri the acute toxicity tests for the untreated drug and the drug irradiated with 5 kGy it was obtained CE5015min of 6.9 % and 32.88 % respectively. These results presented a reduction of the acute toxicity of the test-substances after irradiation.

A ampla utilização de medicamentos, a falta de gerenciamento na produção e no descarte desses produtos, bem como a dificuldade na remoção de resíduos de fármacos das águas residuais durante as fases do tratamento de efluentes tem causado a liberação destes micropoluentes nos recursos hídricos. O cloridrato de fluoxetina, conhecido comercialmente como Prozac®, tem sido muito utilizado em diversos países. Estudos demonstram sua presença no meio ambiente e o potencial de danos que este fármaco pode causar à biota. Desta forma, este trabalho estudou uma tecnologia de tratamento (POA - Processo Oxidativo Avançado) utilizando-se radiação ionizante, proveniente de um acelerador de elétrons, para a degradação do fármaco cloridrato de fluoxetina em solução aquosa e na mistura com esgoto doméstico. Após a irradiação foram feitas análises químicas na solução aquosa do fármaco com Espectrofotometria UV/VIS, Cromatografia Líquida Ultra Rápida (detectores UV/VIS e fluorescência) e quantificação do Carbono Orgânico Total (COT). Também foram empregados ensaios de toxicidade aguda (Daphnia similis e Vibrio fischeri) e crônica (Ceriodaphnia dubia). A eficiência na degradação do fármaco foi superior a 98,00% na menor dose de radiação (0,5 kGy), porém houve baixa taxa de mineralização para as doses aplicadas neste estudo. Para a Daphnia similis na dose de 0,5 kGy houve eficiência de 83,75% na redução da toxicidade do cloridrato de fluoxetina e 87,24% para 5,0 kGy, houve eficiência de 100,00% na redução da toxicidade para o esgoto doméstico e para a mistura (CF + esgoto) 79,32% na dose de 5,0 kGy. A eficiência para a Vibrio fischeri foi de 17,26% (melhor eficiência na dose de 5,0 kGy) e após a correção do pH das amostras a melhor eficiência foi para 20,0 kGy (26,78%), para o esgoto e para a mistura as eficiências ficaram em torno dos 20,00% para todas as doses de radiação aplicadas. Em relação a toxicidade crônica para Ceriodaphnia dubia a eficiência foi de 97,50% para 5,0 kGy. Verificou-se que a Ceriodaphnia dubia possui maior sensibilidade ao fármaco, seguido da bactéria Vibrio fischeri e por fim a Daphnia similis. / Extensive use of drugs, lack of management in the production and disposal of these products as well as the difficulty in removing residues of pharmaceuticals during wastewater treatment phases imply the release of these micropollutants in water resources. Fluoxetine hydrochloride, known commercially as Prozac®, have been often used in many countries. Studies demonstrate their presence in the environment and potential damage that this drug may cause the biota. Therefore, this paper studied a treatment technology (AOP - Advanced Oxidative Process) using ionizing radiation from an electron accelerator, for the degradation of the drug fluoxetine hydrochloride in aqueous solution and mixed with domestic sewage. After irradiation at aqueous solution chemical analyzes at the drug were done using spectrophotometry UV/VIS, Ultra Fast Liquid Chromatography (detectors UV/ VIS and fluorescence) and quantification of Total Organic Carbon (TOC). Acute toxicity tests (Daphnia similis and Vibrio fischeri) and chronic (Ceriodaphnia dubia) were employed. The efficiency for the degradation of the drug was greater than 98.00% at the lowest absorbed dose of radiation (0.5 kGy), however there was low rate of mineralization to the doses applied in this study. The efficiency reduction of toxicity was 83.75% using Daphnia similis at 0.5 kGy of absorbed dose and 87.24% at 5.0 kGy to fluoxetine hydrochloride, efficiency was 100.00% in reducing toxicity to domestic sewage and the mixture (CF + sewage) was 79.32% at a dose of 5.0 kGy. The efficiency to Vibrio fischeri was 17.26% (better efficiency at the dose of 5.0 kGy) and after correction of pH to a better performance was 20.0 kGy (26.78%), for sewage and mixture efficiencies were about 20,00% for all doses of radiation applied. In relation to chronic toxicity effects to Ceriodaphnia dubia efficiency was 97.50% at 5.0 kGy. It was verified that Ceriodaphnia dubia is more sensitive to the drug, followed by the bacterium Vibrio fischeri and finally Daphnia similis.

No description available.

Purpose: Oral vancomycin is a first-line treatment for Clostridium difficile-associated diarrhea. Preparation of oral vancomycin solutions historically has been facilitated by extemporaneous compounding, using various formulas or compounding kits, such as FIRST® - Vancomycin. More recently, FIRVANQ™ (vancomycin HCl) for oral solution was approved by the FDA, replacing the FIRST® compounding kits. Preparation and storage of unit-doses of oral solutions can expedite delivery of the medication to the patient and reduce opportunity for dosing errors. In this study, we evaluated the stored stability of two preparations of vancomycin HCl oral solution (FIRST® – Vancomycin and FIRVANQ™), stored in oral syringes and dosing cups at refrigerated and room temperatures. Methods: Triplicate batches of vancomycin HCl oral solution (50 mg/mL) were prepared using FIRST® - Vancomycin and FIRVANQ™, aliquoted into plastic oral syringes and sealed dosing cups, and stored at refrigerated and room temperatures for a total of six batches. Additionally, remaining samples from FIRVANQ™ batches were unit-dosed in clear Luer-Lok™ syringes and stored under refrigeration as a seventh batch. Samples were removed and analyzed for vancomycin recovery using a previously validated high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method over a 30-day period. Recovery was quantitatively assessed by comparing to a freshly prepared United States Pharmacopoeia (USP) reference standard on each day of sampling. Results: Stability was defined as recovery of 90 - 110% of labeled amount. For all tested samples, the chemical potency remained within the therapeutically acceptable window for the entire study period of 30 days. At room temperature, the FIRST® syringes and cups both retained 95% potency after 30 days. Under refrigeration, this product retained 100% potency and 91% potency in syringes and cups, respectively. Similarly, the FIRVANQ™ room temperature syringes were at 99% recovery and the room temperature cups at 95% recovery after 30 days. Refrigerated FIRVANQ™ retained a potency of 102% potency in the dosing cups after 30 days, and the both syringes types (clear and amber) were 97% and 101%, respectively, recovery during the study period. Conclusion: The percent recovery of vancomycin in each test group remains within 90 – 110% of the labeled amount throughout duration of study (0 – 30 days). Based on this study, unit-dosing has been shown to have a 30-day chemical stability. In this case, unit-dosing not only may be used to improve workflow and reduce dosing errors, but may also have an impact of reducing drug waste due to avoidance of discarding appropriately potent drug product. Additionally, stability within the study period was independent of storage container and condition. Finally, this unit-dosing practice for FIRVANQ™ is equally acceptable in the classic luer-slip amber plastic syringes, and the newer Luer-Lok™ clear plastic syringes.

Although an iontophoretic trans-dermal drug delivery is known as an effective means for drug transportation through the human skin, it is not widely used because of the various side effects that come to life due to a high applied voltage of up to 80V. This study introduces an alternative means of drug transportation through the skin by means of sweat gland activation and reduction of an applied voltage to ensure that the iontophoresis is safe. The skin conductance studies performed on the pulmar area using 50mM of NaCl showed that the activation of sweat glands led to the increase of the skin conductance up to 8-10 times which enabled us to use a lower voltage of 2V in order to achieve noticeable results during the actual drug delivery experiment performed in the points of low ionic resistance that are located on a human biceps, also the application of Vaseline on the experimental surface does not allow the decrease of a skin conductance for as long as 11 hours which enables us to do the drug delivery over a long period of time. Finally, the drug delivery was performed and tested by means of HPLC method.

Fatal and non-fatal opioid overdoses resulting from opioid induced respiratory depression are a significant problem throughout the world. Whilst the opioid receptor antagonist, naloxone hydrochloride, can effectively reverse opioid overdoses, its use is limited because of the adverse effects it produces. These include severe withdrawal and the reversal of analgesia produced by opioid receptor agonists. In this project, the peripherally acting opioid receptor antagonist, naloxone methiodide, was investigated for its potential to reverse opioid induced respiratory depression without altering centrally mediated effects, such as withdrawal. In the publications presented in this thesis, naloxone hydrochloride and naloxone methiodide were shown to effectively reverse the decreases in respiratory rate produced by the administration of morphine, methadone and heroin in mice. Naloxone hydrochloride and naloxone methiodide also reversed the analgesia produced by these opioid receptor agonist treatments, but only naloxone hydrochloride induced significant withdrawal. The doses of naloxone methiodide required to produce the effects described above were higher than the naloxone hydrochloride doses required. Radioligand binding techniques indicated that this was due to a difference in the affinity of naloxone hydrochloride and naloxone methiodide for µ, δ and κ opioid receptor binding sites. Radioligand binding techniques were also used to confirm that naloxone methiodide, or its metabolites, could not readily cross the blood brain barrier. Therefore, the effects of naloxone methiodide appear to be mediated outside the central nervous system. The final publication aimed to extend our knowledge of opioid induced respiratory depression by utilising new radiotelemetry technology to test the efficacy of naloxone methiodide in rats subjected to a chronic opioid administration regime. This experiment showed that circadian rhythm plays a role in the development of tolerance to the cardiorespiratory effects of continuous and chronic methadone administration, and that naloxone hydrochloride and naloxone methiodide treatment can increase respiratory rate and heart rate after this methadone administration. Therefore, naloxone methiodide can effectively antagonise the peripheral effects produced by opioid receptor agonists. Peripherally acting opioid receptor antagonists should be developed in the future to prevent or treat the adverse effects of opioid receptor agonists. / Thesis (Ph.D.)--Department of Clinical and Experimental Pharmacology, 2004.

The aqueous solubility of an active pharmaceutical ingredient (API) is an important property that requires evaluation during early development and prior to formulation of the final product. With general, experimental, solubility testing of different APIs, the question always arises as to whether particle size had been determined beforehand or not. All available literature suggests that particle size, for pharmaceutical powders, does not significantly affect equilibrium solubility. The dissolution rate will differ according to different particle sizes, but the overall results should be identical after equilibrium is established. This study was therefore planned to investigate as to whether different particle size fractions of the same API, dissolving at different rates, would all reach solubility equilibrium within 24 hours. Also, APIs from different solubility classes were investigated, because poorly soluble substances would most likely require a longer period of time to equilibrate. The time period of 24 hours was selected, because many published solubility studies report using that interval and is it the standard for our research group also. Available APIs were selected to determine the influence (if any) of particle size on their equilibrium solubilities and the time required for attaining that status. For the purpose of this investigation, five APIs were selected from compounds at our disposal in-house, ranging from freely soluble to poorly soluble in the order: chloroquine phosphate > pyrazinamide > mefloquine hydrochloride > closantel sodium > roxithromycin. Solubility studies were successfully completed on four of the five APIs selected. For closantel sodium, pyrazinamide and roxithromycin it was demonstrated that the 24 hour test period was sufficient for the attainment of equilibrium solubility, regardless of the particle size fractions tested. Surprisingly, the only API in this study for which 24 hours was an insufficient test period was mefloquine HCl, which was not the least soluble compound tested. Further testing would be required to clarify this anomaly. What was evident from the outcomes of this investigation was that although the ubiquitous 24 hour solubility test may work well in many cases, its suitability should be reviewed on a case-by-case basis and not just for the most poorly soluble compounds. Researchers testing solubility at temperatures lower than 37°C should be especially cautious of using a standardised test period, because equilibrium solubility would take longer to achieve with less energy available to the system. / Thesis (MSc (Pharmaceutics))--North-West University, Potchefstroom Campus, 2013