Validated method for the determination of deflazacort by a flow-injection analysis with UV detection: Application to pharmaceutical formulations

Abstract

A simple, precise, accurate, and fast flow-injection analysis (FIA) method employing UV detection is described for the determination of deflazacort (DEF) in pharmaceutical tablets. The best carrier solvent system consisted of EtOH: sodium dihydrogen phosphate (0.2 M) (20: 80, v/v) (pH 6.0). Related parameters were elucidated and a flow-rate of 1.3 mL min(-1) was used and the analyte was monitored at 247 nm. In the optimum condition, the repeatability was in the range of 0.27-0.41 as intra-day precision. The linearization was tested considering intra- and inter-day experiments in the range of 1.0 x 10(-5) -5.0 x 10(-5) M and good correlation coefficients were obtained. The limit of detection (LOD) and the limit of quantification (LOQ) were calculated to be 2.35 x 10(-7) and 7.04 x 10(-7) M, respectively, as inter-day results. The proposed method was applied to the determination of DEF in pharmaceutical preparations. Conventional UV-spectrophotometry was used as a comparison method and their results were also compared to those of the FIA technique. Insignificant differences between FIA and UV-spectrophotometric results were observed (p < 0.05). In conclusion, the tablets provide the general official requirements, 101.3% and 102.3%, respectively. Therefore, the proposed method is suggested to the routine laboratories for the determination of DEF in tablets.