Validation of quantitative analysis method for triamcinolone in ternary complexes by UV-Vis spectrophotometry

Triamcinolone (TRI), a drug widely used in the treatment of ocular inflammatory diseases, is practically insoluble in water, which limits its use in eye drops. Cyclodextrins (CDs) have been used to increase the solubility or dissolution rate of drugs. The purpose of the present study was to validate a UV-Vis spectrophotometric method for quantitative analysis of TRI in inclusion complexes with beta-cyclodextrin (B-CD) associated with triethanolamine (TEA) (ternary complex). The proposed analytical method was validated with respect to the parameters established by the Brazilian regulatory National Agency of Sanitary Monitoring (ANVISA). The analytical measurements of absorbance were made at 242nm, at room temperature, in a 1-cm path-length cuvette. The precision and accuracy studies were performed at five concentration levels (4, 8, 12, 18 and 20μg.mL-1). The B-CD associated with TEA did not provoke any alteration in the photochemical behavior of TRI. The results for the measured analytical parameters showed the success of the method. The standard curve was linear (r2 > 0.999) in the concentration range from 2 to 24 μg.mL-1. The method achieved good precision levels in the inter-day (relative standard deviation-RSD <3.4%) and reproducibility (RSD <3.8%) tests. The accuracy was about 80% and the pH changes introduced in the robustness study did not reveal any relevant interference at any of the studied concentrations. The experimental results demonstrate a simple, rapid and affordable UV-Vis spectrophotometric method that could be applied to the quantitation of TRI in this ternary complex. Keywords: Validation. Triamcinolone. Beta-cyclodextrin. UV- Vis spectrophotometry. Ternary complexes. RESUMO Valida o de método de análise quantitativa para a triancinolona a partir de complexo ternário por espectrofotometria de UV-Vis A triancinolona (TRI) é um fármaco amplamente utilizado no tratamento de doen as inflamatórias do globo ocular e é praticamente insolúvel em água, o que limita sua utiliza o na forma de colírio. As ciclodextrinas (CDs) têm sido utilizadas com sucesso para aumentar a solubilidade ou velocidade de dissolu o de fármacos. O presente estudo teve como objetivo a valida o de uma metodologia analítica para a TRI a partir de complexos de inclus o com beta-ciclodextrina (B-CD) associada com a trietanolamina (TEA) (complexo ternário) por espectrofotometria de UV-Vis. A valida o do método proposto foi realizada de acordo com os parametros analíticos estabelecidos pela Agência Nacional de Vigilancia Sanitária (ANVISA). As análises quantitativas fo