Desenvolvimento e validação de metodologia para análise de besilato de anlodipino em formas farmacêuticas

Abstract

In this work the quantitative methodologies for determination of amlodipine besilate in tablets and capsules were validated. The methods used for drug determination were: liquid chromatography (LC) and ultraviolet spectrophotometry. The LC system was operated isocratically at controlled-ambient temperature with reverse phase C18 (250 mm x 4.6 mm), using a mobile phase composed of ortho-phosphoric acid 0.1% (v/v) pH 3.0 : acetonitrile (60:40, v/v) at a flow rate of 1.0 mL min-1. The detection was achieved with an ultraviolet detector at 238 nm. In the spectrophotometry method the drug was extracted in 1% of 0,1N hydrochloric acid in methanol (v/v) and its concentration was measured at maximum wavelength of 238 nm. These two methods showed good linearity, precision and accuracy and the results obtained were not statistically different. Moreover, a method for the dissolution of amlodipine besilate in solid dosage formulations was developed and validated. Dissolution studies were conducted by basket and paddle methods at 37 ± 0,5°C in 500 mL of 0,01N hydrochloric acid at 50 rpm. The quantification was achieved by LC and ultraviolet spectrophotometry. The data validation showed good linearity, specificity, accuracy and precision. Afterwards, tests of the dissolution rate and pharmaceutical equivalence of some available commercial formulations were developed. The tests evidenced that most of the commercial products possesse good quality and they are pharmaceutical equivalents.