Desenvolvimento de um novo método para controle de qualidade do cloridrato de paroxetina e do cloridrato de biperideno por dicroísmo circular

Abstract

This paper describes the qualitative and quantitative analysis by circular dichroism (CD) of paroxetine hydrochloride and qualitative analysis of biperiden hydrochloride. It was developed the method a simple, rapid, which uses the differential absorption of circularly polarized light right and left environment for the qualification and quantification of raw materials the drugs mentioned above using the technique by circular dichroism. The method developed followed the criteria of rules and recommended by ANVISA and ICH. The paroxetine hydrochloride and biperiden hydrochloride are chiral drug that can be used for the treatment of depression and Parkinson's, respectively. Paroxetine (PRX), a chiral drug, has two stereogenic carbon atoms in its chemical structure. The PRX, was dissolved in ultrapure water concentration 5,47.10-4 molL-1 DC analysis. Their spectrum showed an intense negative Cotton effect in mdeg - 37.4653. The standard curve the solution of reference a correlation coefficient of 0.9907 for the concentration range of the 0,91.10-4/ 5,47.10-4 molL-1. The limits of detection and quantification were 0,197.10-4 and 0,656.10-4 molL-1, respectively. The repeatability and precision intermediate had variance of 1.32. The results showed good accuracy for interval of 95%. The study showed that the recovery of the extraction method of PRX the drug was effective. The method is robust and the samples were stable to temperature variations. The method was selective for quantification of the drug by evaluating the interference of the excipients. Analyses with biperiden, a substance which has four chiral centers, were performed with the secondary standard BPR and the drug by the DC of molar concentrations 3,21.10-3 and 3,21.10-4 respectively. The samples had EC negative as well as the primary standard USP BPR. The spectrum obtained by theoretical calculation showed a positive Cotton effect of the enantiomers of BPR. These results indicate that one of the enantiomers can BPR is in excess or that the substance is pure or impurities which are chiral.