Dissertations / Theses on the topic 'Stability indicating assay method'

Objectives The objectives of this study included developing and validating a stability-indicating high-performance liquid chromatographic (HPLC) method with ultraviolet (UV) detection for the determination of buprenorphine in a buccal solution for veterinary use, and applying that method to determine the stability of a 3 mg/ml buprenorphine preparation in room temperature and refrigerated storage conditions. This preparation, intended for buccal administration in feline patients, plays an important role in pain management in cats. Methods A stability-indicating HPLC method was developed and validated for system suitability, accuracy, repeatability, intermediate precision, specificity, linearity and robustness based on US Pharmacopeia (USP) General Chapter. The method was then applied to the study of potency changes over 90 days in a buccal buprenorphine solution stored at two temperatures. Results All HPLC-UV method data met acceptable criteria for the quantification of buprenorphine in a buccal solution formulation. The buprenorphine concentrations found in each stability sample remained within the 90–110% of label claim throughout the 90 days of study. All stability test bottles of the buprenorphine buccal solution retained their original appearance. For the room temperature bottles, some white particulate matter was noted in the threads of the container bottles starting at day 21. The pH of the preparations during the course of the study was in the range of 3.57–4.06 and 4.01–4.16 for the room temperature and refrigerated samples, respectively. Conclusions and Relevance Pharmacists have compounded a concentrated 3 mg/ml buccal solution to use easily in the home care or outpatient setting for treatment of feline pain. Prior to this investigation, pharmacists empirically assigned beyond-use dates to this formulation based on standards in USP General ChapterPharmaceutical Compounding – Nonsterile Preparations. This study of a 3 mg/ml buprenorphine buccal solution indicates stability through 90 days.

Stability plays an important role in the development of a new drug product. High Performance Liquid Chromatography (HPLC) is considered a stability indicating method of analysis. It is widely used in the pharmaceutical industry for the quantification of small organic molecules during stability testing. Previous stability studies conducted on Pheroid™-based drug products, experienced problems with the generation of reliable data by means of HPLC analysis. With these studies it was concluded that the inconclusive results could either be attributed to the stability of the delivery system itself and the compatibility of the active pharmaceutical ingredients (API's) with the delivery system, or to the usage of unsuitable HPLC methods. The aims of this study were to: i. determine if the Pheroid™ delivery system changes significantly over time at accelerated storage conditions and how these changes influence the HPLC analysis, ii. determine the effect of the anti-oxidant tert-butylhydroquinone (TBHQ) on the stability and HPLC analysis of the Pheroid™ delivery system, and iii. to suggest a suitable approach for the analysis of Pheroid™-based drug products. Pheroid™ microsponges, containing no API's, were prepared and stored for a period of three months at 5°C, 25°C+60%RH, 30°C+65%RH and 40°C+75%RH. Two of the four Pheroid™ formulations contained an extra anti-oxidant, namely TBHQ. Monthly HPLC analyses were done using existing methods for mefloquine and artesunate. In addition to HPLC analysis, particle size analysis and Confocal Laser Scanning Microscopy (CLSM) were undertaken to support the HPLC results and provide information concerning the overall stability of the Pheroid™ delivery system. After the completion of the above analyses, experiments were carried out to determine whether adjustments to some of the key chromatographic parameters could improve the separation of Pheroid™-based samples. The parameters that were subjected to change included the organic solvent, isocratic versus gradient separation, pH and detection wavelength. Two pro-Pheroid vesicles formulations were prepared and stored for a three month period at 40°C+75%RH only. No API was added to the one formulation while the other contained 2 mg/ml of mefloquine hydrochloride. Results obtained indicated that the Pheroid™ formulations changed after exposure to elevated temperature and humidity. The number of detectable peaks increased, longer run times became necessary and solubility in the sample solvent (methanol) decreased. Solubility of the Pheroid™ formulations in methanol was preserved to some extent by the presence of TBHQ. Physical signs of instability like discolouration and creaming were noted for TBHQ-containing formulations. TBHQ also seemed to have influenced the particle sizes, particle size distributions and structure of the Pheroid™ microsponges. With adjustments made to the HPLC method it was found that: i. the sample solvent is incompatible with the HPLC system, ii. very hydrophobic compounds are present in the Pheroid™-based samples, iii. acetontrile and methanol are unsuitable for both gradient and isocratic separation of Pheroid™-based samples, iv. more Pheroid™ components absorb at shorter wavelengths, and v. small changes in the pH values usually implemented do not influence the retention and selectivity of the Pheroid™ components. The Pheroid™ delivery system proved to be too complex and reversed hydrophobic for phase HPLC analysis. Preparation of the sample by only diluting the Pheroid™ formulations with pure methanol was not optimal. These samples introduced compounds to the column of which some caused interferences with the analyte peak while others were difficult to elute from the column. To continue using HPLC for the analysis of Pheroid™-based drug products, it is therefore recommended that attention should be given to the development of a more appropriate sample preparation procedure, like solid phase extraction or liquid-liquid extraction, one that will eliminate the effects of the Pheroid™ components. Physical instabilities noticed with the addition of TBHQ, suggest that there should also be attended to the compatibility and stability of each of the components in the Pheroid™ delivery system during formulation development.<br>Thesis (M.Sc. (Pharmaceutics))--North-West University, Potchefstroom Campus, 2010.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-06-28T14:51:48Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) UNIVERSIDADE FEDERAL DE PERNAMBUCO (Salvo Automaticamente)_correto.pdf: 1889034 bytes, checksum: eb0752322509ac8a41b42b336e30870a (MD5)<br>Made available in DSpace on 2016-06-28T14:51:48Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) UNIVERSIDADE FEDERAL DE PERNAMBUCO (Salvo Automaticamente)_correto.pdf: 1889034 bytes, checksum: eb0752322509ac8a41b42b336e30870a (MD5) Previous issue date: 2014-05-30<br>A metildopa (a-metil-3, 4-dighidro-l-fenilalanina) é um agente hipotensor de ação central, é uma pró-droga, que exerce sua ação anti-hipertensiva através de um metabólito ativo. A estabilidade é um importante parâmetro para avaliar a segurança, eficácia e qualidade exigidas para o registro sanitário de produtos farmacêuticos. Vários países publicam diretrizes para estabilidade farmacêutica. No Brasil, estes estudos devem ser conduzidos segundo o Guia para a Realização de Estudos de Estabilidade, publicada na resolução - RE n.01 de 29 de julho de 2005 e a RDC 58 de 20 de dezembro de 2013 que estabelece parâmetros para a notificação, identificação e qualificação de produtos de degradação em medicamentos com substâncias ativas sintéticas e semissintéticas, classificados como novos, genéricos e similares e dá outras providências. O objetivo desse trabalho foi desenvolver um método indicativo de estabilidade para comprimidos revestidos de metildopa 500mg, avaliando a especificidade e a seletividade deste método. Para avaliação da especificidade e seletividade do método foram mantidas amostras da metildopa matéria-prima, comprimido revestido 500mg e placebo nas seguintes condições de estresse: hidrólises (ácida, básica e neutra), oxidação e temperatura; as amostras também foram submetidas ao teste de fotoestabilidade. A seletividade do método também foi demonstrada após realização de testes com o padrão primário de metildopa contaminado com a impureza 3-O-metil-metildopa. Os resultados foram analisados segundo dados gerados por cromatografia líquida de alta eficiência (CLAE) com detector de arranjo de diodos (DAD). A 3-O-metildopa apresenta tempo de retenção relativo (TRR) de 1,37 frente à metildopa. A metildopa mostrou-se estável nas hidrólises neutras e ácida menos concentradas bem como na degradação térmica, oxidativa e na fotoestabilidade. Apresentou um decaimento muito acentuado nas condições básicas (NaOH 0,1 e 1,0M), sendo inadequado para o estudo de métodos indicativos de estabilidade como indica a RDC 58 de 2013. A condição mais severa da hidrolise ácida (HCl 5,0M) apresentou um teor de 77,80% para a matéria-prima e 82,99% para o comprimido revestido em comparação com o padrão de trabalho após 72 horas de estudo, ambos apresentaram um pico de degradação com TRR de aproximadamente 2,00. Na condição de hidrólise alcalina menos concentrada (NaOH 0,01M) apareceram produtos de degradação tanto na matéria-prima como para o comprimido revestido de metildopa, porém, o pico que apresenta área significativa apresenta TRR de 0.38 e o teor do fármaco foi de 73,49% para a matéria-prima e 74,48% para o comprimido revestido em comparação com o padrão de trabalho após 72 horas de estudo. Através das análises dos resultados obtidos utilizando as ferramentas de integração e de análise espectral para avaliação da similaridade e pureza dos picos, verifica-se que o método utilizado consegue detectar os produtos de degradação que venham a surgir durante os estudos de estabilidade. O método posteriormente foi validado utilizando como referências a RE 899 de 2003 e a norma técnica da ICH Q2 R1. O método desenvolvido e validado foi utilizado no estudo de estabilidade de um comprimido revestido de metildopa 500mg similar constante no mercado brasileiro, apresentando resultados dentro da especificação exigida para o produto.<br>Methyldopa (a-methyl-3,4-dihydro-l-phenylalanine) is a centrally acting antihypertensive agent, is a prodrug, which exerts its antihypertensive action through an active metabolite. Stability is an important parameter to evaluate the safety, efficacy and quality required for sanitary registration of pharmaceutical products. Several countries publish guidelines for pharmaceutical stability. In Brazil, the stability studies should be conducted according to the guide on conducting stability studies, published in the resolution RE 01 of July 29, 2005 and RDC 58 of December 20, 2013 laying down parameters for notification, identification and qualification of degradation products in medicine with synthetic and semi synthetic active substances classified as new, generic and similar and other measures. The aim of this study was to develop a stability indicating method for coated tablets 500mg of methyldopa following and evaluating the specificity and selectivity of this method. To assess the specificity and selectivity of the method of methyldopa samples were stored raw material, coated tablet 500mg and placebo in the following stress conditions: hydrolysis (acidic, basic and neutral), oxidation, light and temperature. The selectivity of the method was demonstrated after testing with the primary pattern methyldopa contaminated with impurity 3-O-methyl-methyldopa. The results were analyzed according to data generated by high performance liquid chromatography (HPLC) with diode array detector (DAD). 3-O-methyl-methyldopa has RRT 1.37 front methyldopa. Methyldopa was stable in neutral and acidic hydrolysis less concentrated as well as thermal, oxidative degradation and photostability. Showed a dramatic decay in basic conditions (NaOH 0,1 and 1,0M) and unsuitable for the study of stability indicating methods as shown in the RDC 58/ 2013. The most severe conditions of acid hydrolysis (5,0M HCl) showed a content of 77.80 % for the raw material and 82.99 % for the coated tablet compared the standard of work after 72 hours of study, both showed a peak of degradation with TRR approximately 2,00. In the condition of less concentrated alkaline hydrolysis (0,01M NaOH) appeared both in the degradation products as raw material for the coated tablet methyldopa, however, the peak that shows significant area RRT 0,38 and shows content of the drug was 73,49% for raw and 74,48% for the coated tablet compared the standard of work after 72 hours of study. Through the analysis of the results obtained using the tools of integration and spectral analysis for assessing similarity and purity of the peaks, it is found that the method can detect possible degradation products that arise during the stability studies . The method was subsequently validated using as references to RE 899 2003 and the technical standards of the ICH Q2 R1. The developed and validated method was used on a tablet stability study coated methyldopa 500mg similar constant in the Brazilian market, presenting results within the specification required for the product.

Os diuréticos aumentam o fluxo urinário e a excreção de sódio e são utilizados para ajustar o volume e/ou a composição dos líquidos corporais em uma variedade de situações clínicas. A furosemida é um agente diurético potente que induz uma poderosa diurese. É utilizada no tratamento de edema associado com o coração e doenças renais. Nesta pesquisa objetivou-se desenvolver métodos indicativos de estabilidade para a furosemida, por eletroforese capilar em solução livre (FSCE) e cromatografia liquida de alta eficiência (CLAE). O método por FSCE utilizou um capilar de sílica fundida com comprimento total de 30,2 cm x 50,0 &#181;m d.i. O tampão utilizado foi tetraborato de sódio 2,0 mmol L-1 e 10% de metanol, injeção hidrodinâmica 0,5 psi/5s, tensão aplicada +25 kV, detecção em 273 nm e temperatura a 25ºC. O tempo de migração da furosemida foi de 1,8 minutos. O método obteve boa linearidade no intervalo de 70,0 a 130,0 &#181;g.mL-1 com coeficiente de correlação maior de 0,99. Os limites de detecção e de quantificação foram 6,2 &#181;g.mL-1 e 20,6 &#181;g.mL-1, respectivamente. A precisão do sistema foi inferior a 2,0%. A repetibilidade e precisão intermediária foram inferiores a 5,0%. A recuperação média foi de 102,1 %. No teste de especificidade, foram detectados três potenciais produtos de degradação com os seguintes tempos de retenção 1,3 2,0 e 2,2 min. O método por CLAE utilizou uma coluna Shim-pack CLC-ODS(M)® (250mm x4.6mm, 5&#181;m). A fase móvel era constituída de acetonitrila:água (50:50) com 0,1% de ácido fórmico. O fluxo foi de 1.0 mL min-1 e detecção em 273 nm e temperatura a 30 ± 1 ºC. O método apresentou boa linearidade nas concentrações entre 7,0 e 13 &#181;g.mL-1; com coeficiente de correlação maior de 0,99. E tempo de retenção para furosemida foi de 4,9 minutos. Os limites de detecção e de quantificação foram 0,6 &#181;g.mL-1 e 1,9 &#181;g.mL-1, respectivamente. A precisão do sistema foi inferior a 1,0%. A repetibilidade e precisão intermediária foram inferiores a 3,0%. A recuperação média foi de 105,1 %. No teste de especificidade, foram detectados três potenciais produtos de degradação com os seguintes tempos de retenção 2,4, 3,1 e 3,8 min.<br>Diuretics increase urine flow and sodium excretion and are used to adjust volume and / or composition of body fluids in a variety of clinical situations. Furosemide is a potent diuretic agent that induces a strong diuresis. It is used in the treatment of edema associated with heart and kidney disease. This research aimed to develop stability indicative methods for furosemide, by capillary electrophoresis in free solution (FSCE) and high-performance liquid chromatography (HPLC). The method FSCE used a fused silica capillary with a total length of 30.2 cm x 50.0 um di The buffer used was sodium tetraborate 2.0 mmol L-1 and 10% methanol, hydrodynamic injection 0.5 psi / 5s, +25 kV applied voltage, detection at 273 nm and 25 °C. The furosemide migration time was 1.8 minutes. The method achieved good linearity in the range of 70.0 to 130.0 &#181;g.mL-1 with correlation coefficient higher of 0.99. The limits of detection and quantification were 6.2 and 20.6 &#181;g.mL-1 &#181;g.mL-1, respectively. The system accuracy was less than 2.0%. The repeatability and intermediate precision were less than 5.0%. The average recovery was 102.1%. The specificity test detected three potential degradation products with the following retention times 1.3, 2.0 and 2.2 min. The HPLC method used a Shim-pack CLC-ODS (M)® column (250mm x 4.6mm, 5&#181;m). The mobile phase consisted of acetonitrile: water (50:50) with 0.1% formic acid. The flow rate was 1.0 mL min-1, detection at 273 nm and temperature at 30 ± 1°C. The method showed good linearity in concentrations between 7.0 and 13.0 &#181;g.mL-1; with correlation coefficient higher of 0.99. Retention time for furosemide was 4.9 minutes. The limits of detection and quantification were 0.6 &#181;g.mL-1 and 1.9 &#181;g.mL-1, respectively. The system accuracy was less than 1.0%. The repeatability and intermediate precision were less than 3.0%. The average recovery was 105.1%. The specificity test detected three potential degradation products of the following retention times of 2.4, 3.1 and 3.8 min.

O diabetes mellitus (DM) é uma síndrome na qual o metabolismo de hidratos de carbono, gorduras e proteínas está alterado, por falta de secreção de insulina ou por diminuição da sensibilidade tissular a este hormônio. O DM pode ser do tipo I, também denominado diabetes mellitus insulinodependente (DMID), caracterizado pela falta de secreção da insulina, e do tipo II, também denominado diabetes mellitus não insulinodependente (DMNID), caracterizado pela menor sensibilidade dos tecidos efetores às ações metabólicas da insulina. Embora ainda não haja cura definitiva, há vários tratamentos disponíveis que proporcionam qualidade de vida para o paciente portador, como a administração de hipoglicemiantes orais. Nesta pesquisa, objetivou-se desenvolver métodos indicativos de estabilidade para a glibenclamida e o cloridrato de metformina. Assim, foram desenvolvidos métodos de rastreamento ortogonais utilizando a cromatografia líquida de alta eficiência (HPLC) e a eletroforese capilar (CE), metodologias que foram desafiadas com os estudos da degradação forçada. Realizou-se, também, a identificação do principal produto de degradação da glibenclamida utilizando a cromatografia líquida acoplada à espectrometria de massa (LC-MS). O método por HPLC teve o melhor desempenho no monitoramento dos produtos de degradação da glibenclamida, apresentando boa linearidade nas concentrações entre 0,210 e 0,360 mg/mL; com coeficiente de correlação maior de 0,99. A precisão calculada como desvio padrão relativo (DPR) foi menor de 3%, exatidão do método comprovada mediante teste de recuperação, obtendo-se valores de 100±3,0%. No teste de especificidade, foram detectados três potenciais produtos de degradação, com os seguintes tempos de retenção relativos (TRR) de 0,33; 0,46 e 0,83. O método CZE teve o melhor desempenho no monitoramento dos produtos de degradação do cloridrato de metformina, apresentando boa linearidade nas concentrações entre 0,210 e 0,360 mg/mL, com coeficiente de correlação maior de 0,99. A precisão, calculada como DPR, foi menor do que 5%, exatidão do método comprovada mediante o teste de recuperação, obtendo-se valores de 100±3,5%. No teste de especificidade, foram detectados cinco potenciais produtos de degradação com os seguintes TRRs de 0,90; 1,14; 1,35; 1,45 e 1,56.<br>Diabetes mellitus (DM) is a syndrome which alters the metabolism of carbohydrates, fats and proteins by lack of insulin secretion or a decrease in tissue sensitivity to insulin. Type 1 DM is also known as insulin-dependent diabetes mellitus is characterized by lack of insulin secretion. The second type of diabetes known as Type II, also called non-insulin dependent, is characterized by the reduced sensitivity of target tissues to the metabolic actions of insulin. Although there is no definitive cure, there are several treatments available that provide quality of life for the patient how treatment with oral hypoglycemic agents. This study had as objective to developed stability-indicating methods for glibenclamide and metformin hydrochloride. Thus, the techniques used in this study involved high performance liquid chromatography (HPLC) and capillary electrophoresis (CE), and both were challenged with forced degradation studies. The identification of degradation products of glibenclamide was also performed, utilizing the mass spectrometry (MS) technique. However, the HPLC technique had the best performance for monitoring the degradation products of glibenclamide, which showed a good linearity in concentrations between 0.210 - 0.360 mg/ml, with a correlation coefficient greater than 0.99. The precision was calculated as a relative standard deviation (RSD) which was less than 3%; the accuracy of the method calculated as the percent recovery was obtained with the following values: 100 ± 3.0%. On the specificity were detected three potential products of degradation utilizing forced degradation, with the following relative retention times (RRT) 0.33, 0.46 and 0.83. The CZE method had the best performance to monitoring the degradation products of metformin hydrochloride, which showed good linearity of concentrations between 0.210 and 0.360 mg/ml, with a correlation coefficient greater than 0.99. The intra-day and inter-day precision calculated as DPR was less than 5%, and an accuracy of this method was achieved using the values of 100 ± 3.5%. In the specificity were five potential degradation products were detected with the following TRRS: 0.90, 1.14, 1.35, 1.45 and 1.56.

ultravioleta e espectrometria de massas para análise do teor e limite de impurezas e compostos de degradação para o principio ativo farmacêutico ondansetrona e três diferentes formas farmacêuticas foi desenvolvido utilizando conceitos de qualidade analítica por planejamento (aQbD) e validado de acordo com os requerimentos da USP-NF e do ICH. O método desenvolvido apresentou capacidade de separação de vinte compostos detectados nas amostras envolvidas no estudo: o princípio ativo ondansetrona, sete impurezas descritas nos principais compêndios farmacopéicos mundiais (United States Pharmacopeia-National Formulary, European Pharmacopoeia, British Pharmacopoeia e Indian Pharmacopoeia), onze compostos de degradação gerados pelos estudos de estresse e um excipiente. O método final apresentou um tempo de corrida de 14 minutos, com vazão de fase móvel de 0,4 mL/min, detecção de impurezas por ultravioleta a 220 nm e do princípio ativo a 305 nm, com apoio da detecção por espectrometria de massas de alta resolução (QTOF). Em comparação aos métodos requeridos pelas monografias relacionadas à ondansetrona publicadas nos compêndios farmacopéicos citados, o método desenvolvido apresenta uma alternativa eficiente e econômica para a análise de rotina de diferentes formas da matéria-prima ondansetrona (base, cloridrato, diferentes níveis de hidratação) e formas farmacêuticas (comprimidos, comprimidos de desintegração oral e solução injetável), mostrando que a modernização dos métodos cromatográficos, além de garantir a qualidade dos produtos farmacêuticos e promover a saúde da população, tem um impacto relevante na economia da produção e análise de medicamentos e na diminuição do impacto ao meio ambiente<br>An analytical method by ultraperformance liquid chromatography and detection by UV and mass spectrometry for assay and limit test for impurities and degradation compounds for the active pharmaceutical ingredient ondansetron and three different pharmaceutical products was developed using the analytical Quality by Design (aQbD) approach, and was validated according to the USP-NF and ICH requirements. The analytical method was efficient for the separation of twenty different compounds, detected in the samples involved in this study: the active ingredient ondansetron, seven impurities mentioned in the main global pharmacopeial compendia (United States Pharmacopeia-National Formulary, European Pharmacopoeia, British Pharmacopoeia e Indian Pharmacopoeia), eleven degradation compounds detected in the samples from stress studies and one excipient. The final method was composed by a 14 minutes run, using mobile phase flow at 0.4 mL/min, detection by UV at 220 nm for the impurities and degradation compounds and at 305 nm for ondansetron, supported by the high-resolution mass spectrometry detection (QTOF). Comparing the method developed with the chromatographic methods required by the monographs related to ondansetron published in the mentioned pharmacopeial compendia, it represents an efficient and economic alternative to the routine analysis of different ondansetron raw material forms (base, hydrochloride, different hydrates) and pharmaceutical products (tablets, orally disintegrating tablets and injectable), demonstrating the importance of the modernization of analytical procedures, with regard to not only the quality assurance of pharmaceutical products and promotion of public health, but also to the positive impact on the economy and sustainability of the pharmaceutical analysis and manufacturing.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>This work presents the development and validation of analytical methods to assay daptomycin injection. Daptomycin is a drug of a new class of antibiotics, known as cyclic lipopeptides. It was approved in USA in 2003 and in Brazil in 2009. Up to now, there are no reports about methods to assay the drug in pharmaceutical products, both in scientific literature or in official compendia. Methods to identify daptomycin in raw material were realized as solubility, melting point, infrared spectrophotometry (IR), ultraviolet spectrophotometry (UV) and differential scanning calorimetry (DSC) and they showed appropriate results. The following methods to assay daptomycin injection were developed and validated: high performance liquid chromatography (HPLC), microbiological assay (turbidimetric) and UV-spectrophotometry. All of them were validated according current guidelines, by the following parameters: specificity, linearity, precision, accuracy and robustness, being all the requirements met. The mean values of daptomycin assay by the three methods were: 100,23 ± 0,59% (HPLC); 100,96 ± 2,58% (turbidimetric assay) and 98,98 ± 1,35% (UV-spectrophotometry). They were compared by ANOVA, which indicated that HPLC and turbidimetric assay are interchangeable. The stress testing showed that daptomycin is very susceptible to alkaline medium and that the degradation follows first order kinetic, in the conditions adopted. It was found that the degradation product(s) of daptomycin do not have antimicrobial activity. Considering their characteristics, HPLC and turbidimetric assays can be used in routine quality control and in stability studies of daptomycin injection.<br>Este trabalho apresenta o desenvolvimento e validação de métodos analíticos para o doseamento da daptomicina injetável. A daptomicina é um antibiótico pertencente a uma nova classe de antimicrobianos, conhecidos como lipopeptídeos cíclicos. Foi aprovada para comercialização nos Estado Unidos em 2003 e no Brasil em 2009. Até o momento, não foram relatados métodos de quantificação para o fármaco em produtos farmacêuticos, tanto na literatura científica quanto em compêndios oficiais. Foram realizados métodos para a caracterização da matéria-prima como solubilidade, ponto de fusão, espectrofotometria no infravermelho (IV) e na região do ultravioleta (UV) e calorimetria exploratória diferencial (DSC), sendo que os mesmos permitiram a identificação do fármaco na matéria-prima. Os seguintes métodos para análise quantitativa da daptomicina injetável foram desenvolvidos e validados: cromatografia líquida de alta eficiência (CLAE), ensaio microbiológico (método turbidimétrico) e espectrofotometria na região do UV. Todos os métodos foram validados de acordo com as guias vigentes, frente aos parâmetros de especificidade, linearidade, precisão, exatidão e robustez, tendo sido atendidos os requisitos estabelecidos. Os teores médios de daptomicina na formulação em estudo, pelos métodos desenvolvidos (n=12/método) foram: 100,23 ± 0,59% (CLAE); 100,96 ± 2,58% (ensaio microbiológico) e 98,98 ± 1,35% (espectrofotometria no UV). Esses resultados foram comparados pelo teste de ANOVA, que indicou que os métodos de CLAE e microbiológico são intercambiáveis. Pelo estudo de degradação forçada verificou-se que a condição que induz à maior degradação do fármaco é o meio alcalino, sendo que a reação segue cinética de primeira ordem nas condições usadas. Constatou-se ainda que a amostra degradada da daptomicina não tem ação antimicrobiana. Pelas suas características, os métodos de CLAE e microbiológico podem sem usados no controle de qualidade de rotina e em estudos de estabilidade da formulação injetável de daptomicina.

碩士<br>台北醫學院<br>藥學研究所<br>90<br>Abstract Tolmetin (TLM) and Zomepirac (Z) are used as photosensitizing nonsteroidal antiinflammatory drugs (NSAIDs). When TLM and Z were irradiated by a Hanovia 200W high pressure mercury lamp in methanol, a total of 8 photoproducts of TLM; TLM-1 to TLM-8 and 4 photoproducts of Z; Z-1 to Z-4 photoproducts were observed, respectively. Using preparative HPLC, photoproducts were isolated and their chemical structures were elucidated by UV、IR、MS、NMR and LC-MS spectroscopies. Next, a rapid, sensitive, and accurate stability-indicating high perfor- mance liquid chromatographic assay method for determining the degra- dation of TLM and Z was developed and vali- dated under acidic, basic, or photo-irradiated conditions. The quantitation was monitored with an Inertsil ODS-3V column using a mobile phase of methanol- 0.3%acetic acid = 64:36 (v/v) for TLM and acetonitrile- methanol - 0.3%acetic = 2:64:34(v/v) for Z detector set at 254nm. The related satistics of the developed methods including the system criteria, peak integrity, and resolution among the parent drug and its degradation products were calculated. The C.V.(%) of intraday and interday tests were lower than 2.3% and 4% , respectively. The percent recovery were between 97.14% ~ 101.73 %. Our established HPLC assay method shows good selectivity and specificity which is suitable for the stability measurement of TLM and Z. The rates of photodegradation between TLM and Z present significant difference, no mater the solvent is MeOH or 20% MeOH/H2O. When proceeding first order graphical analysis of these two compounds, we find that k of TLM is almost ten folds to B. After that, we use TLM, which possess more sensitive property to UV light. With different concentrations, alcohol solvents, and concentrations of 20% MeOH/H2O, to look forward to find out the exact photokinetic model of TLM. In our experimental model, the kinetic of TLM of high concentration is zero order. As for the results of using three alcoholic solvents, they showed an inverse proportional relationship between kinetics and dielectric constant of TLM. Hence we supposed that photokinetics of TLM might go through free radical reaction instead of ionic reaction.

A stability-indicating HPLC method was developed and validated for the quantitative determination of orlistat in capsule dosage forms. An isocratic separation was achieved using a Perfectsil® target ODS-3, 250 mm × 4.6 mm i.d., 5 µm particle size column with a flow rate of 0.7 ml/min and using a UV detector to monitor the eluate at 210 nm. The mobile phase consisted of methanol:acetonitrile:trifluoroacetic acid (82.5:17.5:0.01, v/v/v). The drug was subjected oxidation, hydrolysis, photolysis and heat to apply stress conditions. Complete separation was achieved for the parent compound and all degradation products in an overall analytical run time of approximately 15 min with the parent compound orlistat eluting at approximately 9 min. The method was linear over the concentration range of 0.02–0.75 mg/ml (r = 0.9998) with a limit of detection and quantitation 0.006 and 0.02 mg/ml, respectively. The method has the requisite accuracy, selectivity, sensitivity and precision to assay orlistat in capsules. Degradation products resulting from the stress studies did not interfere with the detection of orlistat and the assay is thus stability-indicating.

A stability-indicating high-performance liquid chromatographic method with on-line clean-up has been developed for the analysis of betamethasone 17-valerate in topical dosage forms. A short pre-column containing 10 μm octadecylsilane mounted into the sample loop position of an injection valve was used as the primary clean-up step. The utilization of a diode-array UV detector allowed the quantitative analysis of betamethasone 17-valerate together with its degradation product, betamethasone 21-valerate, as well as the qualitative analysis of these compounds, relevant internal standards and the preservatives chlorocresol and methyl hydroxybenzoate contained in the cream and lotion formulations, respectively. Typically, cream and lotion dosage forms were dissolved in acetonitrile and ointments in tetrahydrofuran, internal standards added and aliquots injected onto the analytical system. Dosage form excipients were retained on the loop column and back-flushed to waste with the aid of a second solvent pump while components of interest were allowed to transfer to the analytical column for quantitative analysis. The method is accurate, precise and stability indicating and permits the rapid on-line analysis of betamethasone 17-valerate from complex topical formulation matrices without prior extractions.

A simple, rapid, precise and accurate isocratic reversed-phase stability-indicating HPLC method was developed and validated for the simultaneous determination of atorvastatin (AT) and amlodipine (AM) in commercial tablets. The method has shown adequate separation for AM, AT from their associated main impurities and their degradation products. Separation was achieved on a Perfectsil® Target ODS-3, 5 μm, 250 mm × 4.6 mm i.d. column using a mobile phase consisting of acetonitrile–0.025 M NaH2PO4 buffer (pH 4.5) (55:45, v/v) at a flow rate of 1 ml/min and UV detection at 237 nm. The drugs were subjected to oxidation, hydrolysis, photolysis and heat to apply stress conditions. The linearity of the proposed method was investigated in the range of 2–30 μg/ml (r = 0.9994) for AT and 1–20 μg/ml (r = 0.9993) for AM. The limits of detection were 0.65 μg/ml and 0.35 μg/ml for AT and AM, respectively. The limits of quantitation were 2 μg/ml and 1 μg/ml for AT and AM, respectively. Degradation products produced as a result of stress studies did not interfere with the detection of AT and AM and the assay can thus be considered stability-indicating.

A simple, sensitive and reliable high-performance liquid chromatographic procedure has been developed for the determination of erythromycin in human serum and urine using amperometric detection. A solid-phase extraction procedure was used followed by chromatography on a reverse-phase column. The mean recovery of erythromycin from serum and urine was 80%. This method allows both erythromycin and its principle degradation product, anhydroeythromycin, to be determined during a period of sample storage at 4 degree C and minus 15 degree C. The method is sufficiently sensitive and precise and is thus highly suited for use in both pharmacokinetic and stability studies.

A single stability-indicating assay for oxytocin (OT) in pharmaceutical dosage forms using gradient elution over 21 min has been reported in the literature. Furthermore, published and compendial methods for the analysis of OT containing dosage forms also involve using HPLC with gradient elution and complicated mobile phases that include hydrophobic ion pairing agents. A simple isocratic and stability-indicating assay was developed and validated. The conditions are as follows, column: Phenomenex® C18 Hypersil, 5 μm packing, 4.6 mm × 150 mm with acetonitrile–phosphate buffer (pH 5; 0.08 M) (20:80) as the mobile phase with UV detection at 220 nm The method was found to be specific for OT in the presence of degradation products and chlorbutol (preservative) with an overall analytical run time of 16 min. Accuracy was determined to be 0.77–1.18% bias for all samples tested. Intra-assay precision (repeatability) was found to be 0.22–1.04%R.S.D. while the inter-day precision (intermediate precision) was found to be 1.27–1.68%R.S.D. for the samples studied. The calibration curve was found to be linear with the equation y = 1.81x + 0.02 and a linear regression coefficient of 0.9991 over the range 0.4–12.0 IU/ml. The LOD and the LOQ were determined to be 0.1 and 0.4 IU/ml, respectively. Syntocinon®, a commercially available dosage form of OT was assayed resulting in 100.5–106.6% recovery of the label claim and an average of 10.04 IU/ml.

Introduction: The development of a reliable in vitro permeation system necessitates the use of a precise and accurate method of quantifying the amount of permeant partitioning from the membrane into the cell receptor phase. Aqueous donor and receptor chamber fluids have been used in the majority of reported investigations, which makes quantitative permeant analysis relatively facile. Alternatively, radiolabelled diffusants have been used and flux rates monitored by scintillation counting, obviating the need for chromatographic separation of the receptor-phase components. However, this technique is not applicable when nonlabelled compounds or commercial dosage forms are to be evaluated by a cell system. Furthermore, several studies indicate that aqueous receptor phases may not present an optimal partitioning environment for certain lipophilic permeants (1-4), thereby impairing accurate flux monitoring due to limited diffusant solubility. Several attempts have therefore been made to improve the partitioning environment within these systems, by the addition of surfactants for example (4). A lipophilic receptor environment appears beneficial for corticosteroid partitioning, and thus, the use of isopropyl myristate has been investigated because of its bipolar properties that tend to mimic the biochemical composition of the skin (5,6). Betamethasone 17-valerate and its 21-valerate degradation product are highly soluble in isopropyl myristate and this nonaqueous solvent will not augment C-17-to-C-21 ester degradation reactions.

碩士<br>大仁科技大學<br>製藥科技研究所<br>100<br>Rosuvastatin calcium, bis [(E)-7 [4-(4-fluorophenyl)-6 isopropyl- 2-[methyl (methyl-sulphonyl) amino] pyrimidin-5-yl] (3R, 5S) -3,5-dihydroxyhept-6-enoic acid] calcium salt, was approved by the US FDA in August 2003 to reduce cholesterol levels in patients with hypercholesterolaemia. This agent is a selective, potent and competitive inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase catalizing the conversion of HMG-CoA to mevalonate, which is an early and rate-limiting step in cholesterol biosynthesis. In the literature, the Rosuvastatin calcium degraded after sun exposure. The major degradation products are the corresponding (3R, 5S) lactone and an oxidation product in which the hydroxy group adjacent to the carbon-carbon double bond is oxidized to a ketone functionality. In this study, we developed a Rosuvastatin calcium bioequivalent product to stabilizing this compound by using different amino acid with different proportions (1:1, 1:2, 1:4) for stability test at different temperatures (75℃, 100 ℃). The stability test results were compared with different stabilizing agents which literature reported in the past including Anhydrous calcium hydrogen phosphate, Magaldrate, Silicon magnesium aluminate, Magnesium hydroxide, and Calcium acetate. The amount of this compound was quantified by means of a validated high-performance liquid chromatography (HPLC) method with a C -18 column. The Stability-Indicating method validation (SIM ) requires to force decomposition studies under a variety of conditions, such as pH, light, oxidation, dry heat, and separation of drug from degradation products. The method validation criteria, system suitability, linearity, specificity, and accuracy, are reported according to the current Taiwan Department of Health, Good Manufacturing Practices guideline. The method was proved to support analysis of Rosuvastatin tablet and its degradation products. The SIM results showed that the Rosuvastatin calcium compound had higher degradation rate under the acidic environment, and samples powder showed a yellow discoloration reaction under the sunlight and heating. Rosuvastatin calcium SIM quantitative analysis method validation obtained the correlation coefficient R² = 0.9999 at concentration linear range in the 83.5 ~ 124.8 l / ml. The finished products, Crestatin® tablets, were stored at 25℃( 60 % ± 5% RH), 30℃( 65 % ± 5 % RH ), 40℃( 75 % ± 5 % RH) and 75℃( 75 % ± 5 % RH ) and analyzed samples at different storage times. The results showed a first-order kinetic degradation reaction and the predict expiration date was 253.3294 months at 25℃. Therefore, the shelf life of finished products is more than 2 years. The stability dissolution test of Crestatin® tablets was conducted by comparing in different temperatures storage and different media solution (pH 6.6 Buffer or 0.1 N HCl) according to FDA Scale-UP and Post-Approval Changes (SUPAC) statistical methodology to carry out in-vitro dissolution curve ratio comparison. The dissolution curve factors are the similarity factor f2 and difference factors f1 for comparison. The results showed that the f1 value and f2 value were within the acceptable range, indicating that the dissolution rate was independent of temperature and storage times. In this study, we tried to mix different amino acids to develop a stable formulation. Based on the results, it was found that some amino acids, L-Lysine and L-Tyrosine, containing more basic functional groups, were able to stabilize Rosuvastatin compounds.

Trabalho Final de Mestrado Integrado, Ciências Farmacêuticas, Universidade de Lisboa, Faculdade de Farmácia, 2014<br>Force degradation study is an important tool in pharmaceutical process in order to develop stability-­‐indicating methods that lead to quality data and to understand degradation pathways of drug substances and drug product. In this study, Fencarol 10mg/mL solution for injection was submitted to different conditions to determine the effect of excipients present in the formulation in assessing drug product stability and to develop and demonstrate the specificity of stability-indicating method.

A stability-indicating high performance liquid chromatographic(HPLC) method was developed and validated for the quantitation and dissolution determination of topiramate in tablet dosage forms. An isocratic separation was achieved using a phenyl column with a flow rate of 1 mL/min using UV detection at 264 nm. Topiramate has low UV absorbtivity and was subjected to derivatization with 9-fluorenylmethyl chloroformate (FMOC-Cl). The mobile phase for the separation consisted of acetonitrile: 50 mM sodium dihydrogen phosphate(NaH2PO4) containing 3 % v/v triethylamine (pH 2.8) in a 48:52 v/v ratio. Topiramate was subjected to oxidation, hydrolysis, photolysis and heat for the purposes of stress testing. Separation was achieved for the parent compound and all the degradation products in an overall analytical run time of approximately 15 min with the parent compound topiramate eluting at approximately 9.2 min. The method was linear over the concentration range of 1-100 μg/mL (r = 0.9996) with limits of quantitation and detection of 1 and 0.3 μg/mL, respectively.