Desenvolvimento de novos procedimentos analíticos para a determinação de paracetamol em amostras de medicamentos
Data
2009-01-20
Autores
Sequinel, Rodrigo [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Este trabalho propõe o desenvolvimento de novos procedimentos analíticos voltados para a determinação de paracetamol em formulações farmacêuticas. Num primeiro momento, o procedimento foi baseado na hidrólise ácida do paracetamol (PCT) à p-aminofenol (PAP), seguido pela instantânea reação deste com p-dimetilaminocinamaldeído (p-DAC), em meio micelar, para formar um produto vermelho, o qual pôde ser monitorado por espectrofotometria (λmáx = 530 nm), 10 minutos após o início da reação. A hidrólise realizada em forno de microondas foi uma estratégia adotada como alternativa ao moroso processo de hidrólise convencional realizado em banho de água fervente. Estudos preliminares realizados em nosso laboratório, demonstraram ser efetiva a utilização de meio micelar – com dodecil sulfato de sódio (SDS), a fim de tornar o método mais sensível. Em seguida, os efeitos de todos os parâmetros envolvidos no processo analítico foram investigados em detalhes por meio de metodologias de planejamento de experimentos, para determinação das melhores condições experimentais para realização das análises. Sob as condições tidas como ideais, o método apresentou faixa linear de trabalho entre 1,3 x 10-6 – 2,6 x 10-5 mol L-1 (0,2 – 3,9 μg mL-1), com excelente coeficiente de correlação linear (r = 0,9996). O limite de detecção foi de 1,7 x 10-7 (30 ng mL-1). Num segundo momento, parte do procedimento analítico foi incorporada a um sistema automatizado de análise por injeção em fluxo com detecção espectrofotométrica. O novo procedimento analítico adotado apresentou uma ampla faixa linear de trabalho, entre 5,37 x 10-6 – 1,29 x 10-4 mol L-1 (0,8 – 19,5 μg mL-1), com coeficiente de correlação linear de 0,9998. O emprego deste sistema automatizado de análise proporcionou simplicidade e uma maior rapidez na realização das análises. Ambos os procedimentos...
This work proposes the development of new analytical procedures for the determination of paracetamol in pharmaceuticals preparations. At first moment, procedure was based in the paracetamol (PCT) acid hydrolysis to p-aminofenol (PAP), followed by the instantaneous reaction of this with p-dimethylaminocinnamaldehyde (p-DAC), in micellar media in order to form a red product, which could be monitored by spectrophotometry (λmáx = 530 nm), 10 minutes after the beginning of the reaction. The hydrolysis carried out in microwave oven was a strategy adopted like alternative to the slow conventional hydrolysis carried out in boiling water bath. Preliminary studies carried out in the laboratory, showed to be efficient the utilization of micellar media – with dodecil sulphate of sodium (SDS) in order to obtain the most sensible method. Furthermore, the effects of all parameters involved in the analytic process were investigated in details by means of experiments planning methodologies for determination of the best experimental conditions to carry out the analysis. Under the ideals conditions, the method presented linear work range between 1.3 x 10-6 – 2.6 x 10-5 mol L-1 (0.2 – 3.9 mL-1), with excellent correlation coefficient (r = 0,9996). The limit of detection was 1.7 x 10-7 (30 ng mL-1) In a second moment, part of the analytical procedure was incorporated to an automated flow injection analysis with spectrophotometric detection. The adopted new analytical procedure presented a wide linear work range, between 5.37 x 10-6 – 1.29 x 10-4 mol L-1 (0.8 – 19.5 mL-1), with correlation coefficient of 0.9998. The employment of this automated system of analysis provided simplicity and a bigger quickness in the accomplishment of the analysis. Both the developed procedures were applied in the determination of paracetamol in medicines and were subsequently compared with the official method for the determination of PCT in pharmaceuticals formulations.
This work proposes the development of new analytical procedures for the determination of paracetamol in pharmaceuticals preparations. At first moment, procedure was based in the paracetamol (PCT) acid hydrolysis to p-aminofenol (PAP), followed by the instantaneous reaction of this with p-dimethylaminocinnamaldehyde (p-DAC), in micellar media in order to form a red product, which could be monitored by spectrophotometry (λmáx = 530 nm), 10 minutes after the beginning of the reaction. The hydrolysis carried out in microwave oven was a strategy adopted like alternative to the slow conventional hydrolysis carried out in boiling water bath. Preliminary studies carried out in the laboratory, showed to be efficient the utilization of micellar media – with dodecil sulphate of sodium (SDS) in order to obtain the most sensible method. Furthermore, the effects of all parameters involved in the analytic process were investigated in details by means of experiments planning methodologies for determination of the best experimental conditions to carry out the analysis. Under the ideals conditions, the method presented linear work range between 1.3 x 10-6 – 2.6 x 10-5 mol L-1 (0.2 – 3.9 mL-1), with excellent correlation coefficient (r = 0,9996). The limit of detection was 1.7 x 10-7 (30 ng mL-1) In a second moment, part of the analytical procedure was incorporated to an automated flow injection analysis with spectrophotometric detection. The adopted new analytical procedure presented a wide linear work range, between 5.37 x 10-6 – 1.29 x 10-4 mol L-1 (0.8 – 19.5 mL-1), with correlation coefficient of 0.9998. The employment of this automated system of analysis provided simplicity and a bigger quickness in the accomplishment of the analysis. Both the developed procedures were applied in the determination of paracetamol in medicines and were subsequently compared with the official method for the determination of PCT in pharmaceuticals formulations.
Descrição
Palavras-chave
Quimica analitica, Espectrofotometria, Paracetamol - Formas farmaceuticas, Analytical chemistry
Como citar
SEQUINEL, Rodrigo. Desenvolvimento de novos procedimentos analíticos para a determinação de paracetamol em amostras de medicamentos. 2009. 76 f. Dissertação (mestrado) - Universidade Estadual Paulista, Instituto de Química, 2009.