Insulin Evaluation in Pharmaceuticals: Variables in RP-HPLC and Method Validation

Abstract

In this paper different factors, including solvent composition, pH, flow rate, temperature and organic modifier volatility, were examined for their effects on the resolution of Insulin by Reversed Phase High-Performance Liquid Chromatography (RP-HPLC). At the same time several insulin formulations from different pharmaceutical companies have been analyzed for the existence of degradation products. Method validation and reproducibility have been determined by means of two different chromatographic systems. Variation of key parameters demonstrated that a decrease in pH (<3.8) provides a good peak shape, at the same time enhances the insulin retention. An increase in temperature, decreased retention time and enhanced resolution. This information has been applied to insulin formulation assay, where no degradation products were found.