The evaluation of alternative method of ferrous ions assessment in pharmaceutical preparations.

Abstract: The atomic absorption spectrometry (AAS) method is one of the most accessible procedures for ferrous ions testing in various compositions including pharmaceutical preparations. The aim of the study was to develop and partially validate analytical method which could be an excellent alternative to the routine procedure performed within dissolution studies. Electric conductivity is simple, fast, and hassle-free method. The samples during dissolution process were measured using conductivity probe in entire dissolution assessment protocol. The conductivity results were compared to data obtained from AAS. The dissolution studies were performed according to modified pharmacopoeial standards, in 900 cm of purified water as an acceptor medium, at 37 °C, until the achievement of an equilibrium state for every tested composition. Validity study of the developed method confirmed acceptable linearity of obtained calibration plots ( > 0.9553). Linearity at 100% level was found to be 100.59, 97.49, and 94.82, respectively, for drug compositions A, B, and C. Precision results were 100.45, 95.97, and 95.73, respectively, for A, B, and C, with RSD below 2% between all samples in all above mentioned formulations. The drug composition D hindered the proper validation of the method due to the high variability between samples. The method has acceptable performance features for evaluation of three of four solid drug composition containing ferrous ions.