Development and validation of a liquid chromatographic method for the analysis of squaric acid dibutyl ester and its impurities

摘要

A simple, fast and selective stability indicating liquid chromatographic method has been described for the simultaneous determination of squaric acid dibutyl ester and its impurities. The chromatographic separation was achieved on a C2 column (250 mm x 4.6 mm i.d., 5 mu m) using a mobile phase consisting of 0.15% phosphoric acid - acetonitrile - methanol (30:60:10, v/v/v). Isocratic elution was performed at a flow rate of 1.0 mL min(-1). The analytes were detected by UV at 252 nm. The method was validated according to the ICH guidelines and satisfactory results were obtained. The specificity of the developed method was tested using forced degradation solutions of the drug substance.