Made available in DSpace on 2014-12-17T14:16:30Z (GMT). No. of bitstreams: 1 MarceloVPA_DISSERT.pdf: 3152615 bytes, checksum: 2a3513c0df769468fec98423bf2dba29 (MD5) Previous issue date: 2013-03-21 / Tuberculosis is a serious disease, but curable in practically 100% of new cases, since complied the principles of modern chemotherapy. Isoniazid (ISN), Rifampicin (RIF), Pyrazinamide (PYR) and Chloride Ethambutol (ETA) are considered first line drugs in the treatment of tuberculosis, by combining the highest level of efficiency with acceptable degree of toxicity. Concerning USP 33 - NF28 (2010) the chromatography analysis to 3 of 4 drugs (ISN, PYR and RIF) last in average 15 minutes and 10 minutes more to obtain the 4th drug (ETA) using a column and mobile phase mixture different, becoming its industrial application unfavorable. Thus, many studies have being carried out to minimize this problem. An alternative would use the UFLC, which is based with the same principles of HPLC, however it uses stationary phases with particles smaller than 2 ?m. Therefore, this study goals to develop and validate new analytical methods to determine simultaneously the drugs by HPLC/DAD and UFLC/DAD. For this, a analytical screening was carried out, which verified that is necessary a gradient of mobile phase system A (acetate buffer:methanol 94:6 v/v) and B (acetate buffer:acetonitrile 55:45 v/v). Furthermore, to the development and optimization of the method in HPLC and UFLC, with achievement of the values of system suitability into the criteria limits required for both techniques, the validations have began. Standard solutions and tablets test solutions were prepared and injected into HPLC and UFLC, containing 0.008 mg/mL ISN, 0.043 mg/mL PYR, 0.030 mg.mL-1 ETA and 0.016 mg/mL RIF. The validation of analytical methods for HPLC and UFLC was carried out with the determination of specificity/selectivity, analytical curve, linearity, precision, limits of detection and quantification, accuracy and robustness. The methods were adequate for determination of 4 drugs separately without interfered with the others. Precise, due to the fact of the methods demonstrated since with the days variation, besides the repeatability, the values were into the level required by the regular agency. Linear (R> 0,99), once the methods were capable to demonstrate results directly proportional to the concentration of the analyte sample, within of specified range. Accurate, once the methods were capable to present values of variation coefficient and recovery percentage into the required limits (98 to 102%). The methods showed LOD and LOQ very low showing the high sensitivity of the methods for the four drugs. The robustness of the methods were evaluate, facing the temperature and flow changes, where they showed robustness just with the preview conditions established of temperature and flow, abrupt changes may influence with the results of methods / A tuberculose ? uma doen?a grave, por?m cur?vel em praticamente 100% dos casos novos, desde que obedecidos os princ?pios da moderna quimioterapia. S?o considerados f?rmacos de 1? linha no tratamento ? tuberculose: isoniazida, pirazinamida, etambutol e rifampicina. De acordo com USP 33 - NF28 (2010) as an?lises cromatogr?ficas para 3 dos 4 f?rmacos (isoniazida, pirazinamida e rifampicina) duram em m?dia 15 minutos e mais 10 minutos para a obten??o do 4? f?rmaco (etambutol) utilizando outra coluna, com outra mistura de fase m?vel, tornando esta aplica??o na pr?tica industrial desfavor?vel. Uma das alternativas ? utilizar o CLUE, o qual baseia-se nos mesmos princ?pios da CLAE, por?m utiliza fases estacion?rias com part?culas menores que 2 ?m. Dessa forma pretende-se com o presente estudo desenvolver e validar novos m?todos anal?ticos para determina??o simult?nea de tuberculost?ticos por CLAE/DAD e CLUE/DAD. Para isto, foi realizado um screening anal?tico, o qual verificou que ? necess?rio um gradiente de sistema de fase m?vel A (tamp?o acetato:metanol 94:6 v/v) e B (tamp?o acetato:acetonitrila 55:45 v/v). Posteriormente, ao desenvolvimento e otimiza??o do m?todo em CLAE e CLUE com a obten??o dos valores de adequabilidade do sistema dentro dos limites de aceita??es vigente para ambos as t?cnicas, as valida??es deram-se in?cio. Solu??es padr?es e solu??es testes dos comprimidos foram preparadas e injetadas no CLAE e CLUE, contendo isoniazida, pirazinamida, etambutol e rifampicina nas concentra??es de 0,008, 0,043, 0,030 e 0,016 mg.mL-1, respectivamente. A valida??o dos m?todos anal?ticos foram realizadas para: especificidade / seletividade, intervalos da curva anal?tica, linearidade, limite de detec??o, limite de quantifica??o, exatid?o, precis?o (repetibilidade, precis?o intermedi?ria) e robustez. Os m?todos foram adequados para determina??o dos 4 f?rmacos separadamente sem interfer?ncia nos demais. Precisos, devido ao fato de que os m?todos demonstraram que mesmo com varia??o de dias, al?m da repetibilidade, os valores ficaram dentro da faixa preconizada na legisla??o vigente. Lineares (R > 0,99), ou seja, os m?todos foram capazes de demonstrar que os resultados obtidos eram diretamente proporcionais ? concentra??o do analito na amostra, dentro de um intervalo especificado. Exatos, uma vez que os m?todos foram capazes de apresentar valores de coeficiente de varia??o e porcentagem de recupera??o dentro dos limites exigidos (98 a 102%). Os m?todos mostraram LD e LQ com n?veis baixos demonstrando que os m?todos possuem elevada sensibilidade aos quarto f?rmacos. A robustez foi avaliada frente ?s altera??es de temperatura e fluxo, onde os m?todos demonstraram-se robustos apenas nas condi??es previamente estabelecidas de temperatura e fluxo, altera??es bruscas podem acarretar influ?ncia nos resultados dos m?todos

Introduction: No Fixed-Dose Combination (FDC) formulations currently exist for pediatric tuberculosis (TB) treatment. Earlier work implemented, in the software NONMEM, a rational method for optimizing design and individualization of pediatric anti-TB FDC formulations based on patient body weight, but issues with parameter estimation, dosage strata heterogeneity and representative pharmacokinetics remained. Aim: To further develop the rational model-based methodology aiding the selection of appropriate FDC formulation designs and dosage regimens, in pediatric TB treatment. Materials and Methods: Optimization of the method with respect to the estimation of body weight breakpoints was sought. Heterogeneity of dosage groups with respect to treatment efficiency was sought to be improved. Recently published pediatric pharmacokinetic parameters were implemented and the model translated to MATLAB, where also the performance was evaluated by stochastic estimation and graphical visualization. Results: A logistic function was found better suited as an approximation of breakpoints. None of the estimation methods implemented in NONMEM were more suitable than the originally used FO method. Homogenization of dosage group treatment efficiency could not be solved. MATLAB translation was successful but required stochastic estimations and highlighted high densities of local minima. Representative pharmacokinetics were successfully implemented. Conclusions: NONMEM was found suboptimal for the task due to problems with discontinuities and heterogeneity, but a stepwise method with representative pharmacokinetics were successfully implemented. MATLAB showed more promise in the search for a method also addressing the heterogeneity issue.