Spectrophotometric and HPLC determination of deflazacort in pharmaceutical dosage forms

Deflazacort (DFZ) is a glucocorticoid used as an anti-inflammatory and immunosuppressant drug. No official methods are available for DFZ determination in pharmaceutical formulations. The objective of this study was to develop, validate and compare spectrophotometric (UV and colorimetric) and high-performance liquid chromatography (HPLC) methods, for the quantitative determination of DFZ in tablets and oral suspension. For the UV method, ethanol was used as the solvent, with detection at 244 nm. The colorimetric method was based on the redox reaction with blue tetrazolium in alkaline medium, with detection at 524 nm. The method by HPLC was carried out using a C18 column, mobile phase consisting of acetonitrile:water (80:20, v/v) with a flow rate of 1.0 mL min-1 and detection at 244 nm. The methods proved linear (r > 0.999), precise (RSD < 5 percent) and accurate (recovery > 97 percent). Statistical analysis of the results indicated that the UV and HPLC methods were statistically equivalent, while the values obtained for the colorimetric method differed significantly from the other methods.

O deflazacorte (DFZ) é um fármaco glicocorticóide usado como antiinflamatório e imunossupressor. Métodos oficiais não estão disponíveis para a determinação de DFZ em formas farmacêuticas. Este estudo teve como objetivo desenvolver, validar e comparar métodos por espectrofotometria (UV e colorimetria) e cromatografia líquida de alta eficiência (CLAE), na determinação quantitativa de DFZ em comprimidos e suspensão oral. O método por UV utilizou etanol como solvente, com detecção em 244 nm. O método colorimétrico foi baseado na reação de redução com azul de tetrazólio em meio alcalino, com detecção em 524 nm. O método por CLAE utilizou coluna C18; fase móvel constituída de acetonitrila:água (80:20, v/v), com fluxo de 1,0 mL min-1 e detecção em 244 nm. Os métodos foram lineares (r > 0,999); precisos (RSD < 5 por cento), e exatos (recuperação > 97 por cento). As análises estatísticas dos resultados obtidos indicaram que os métodos por UV e por CLAE foram estatisticamente equivalentes, enquanto os valores obtidos para o método colorimétrico diferiram significativamente dos demais métodos.

HIV/AIDS treatment and physicochemical quality control of medicines: evaluation of non-generic lamivudine + zidovudine tablets manufactured in Brazil

In this work it was evaluated the physicochemical quality of lamivudine + zidovudine tablets, whose association belongs to the list of drugs distributed by the Brazil's National Program on Sexually Transmitted Diseases and AIDS. Four non-generic products (lamivudine + zidovudine tablets) were analyzed. They were obtained from different Brazilian manufacturers, besides a reference product. The quality was evaluated by physicochemical tests described in the official codes. A validated reversed-phase high performance liquid chromatography (HPLC) method was used for the assay of the active substances. All samples were in accordance to the requisites in relation to their physicochemical characteristics. Dissolution studies showed similar drug percentual dissolved among all samples. The results reflect the interest of the national pharmaceutical industry to ensure the delivery of safer and cheaper drugs to the Brazilian people, with particular importance in the National Program on Sexually Transmitted Diseases and AIDS.