Preparation of Highly Purified Human Chorionic Gonadotrophin by Isoelectric Focusing

Abstract

Highly purified human chorionic gonadotrophin, assaying 15000–17000 IU/mg in three different bioassay systems, has been obtained from a crude commercial preparation. The purification method is a simple and rapid two‐step procedure, based on preparative iso‐electric focusing on sucrose density gradient (Ampholine pH range 3–10), followed by chromatography on Sephadex G‐100. The purified gonadotrophin (mol. wt 65000), obtained from an iso‐electric pH of 4.3, moved as a single band in polyacrylamide gel electrophoresis at a pH 8.3 and showed a single precipitation line in immunoelectrophoresis. The immunological and biological activities of protein components obtained from various iso‐electric zones during fractionation are reported.