A high performance liquid chromatographic method for the determination of lnsulin in preparations is described. Insulin was eluted on Nucleosil 5CN as packing material with acetonitrile-water-acetic acid (33 : 67 : 2) containing sodium octanesulfonate as mobile phase. The assay results of 7 preparations was 37.9-41.2 IU/ml for these indicated potency of 40 IU/ml and coefficient of variations were 0.85-2.10% (n=3).
