A continuous affinity ultrafiltration process for trypsin purification

Abstract

A continuous process has been devised and tested for purification of a crude trypsin preparation from pig pancreas. The development was based on the principles of affinity chromatography and Ultrafiltration. Trypsin was selectively attracted by a water-soluble high molecular weight (>100,000) polymer, bearing a potent and specific trypsin inhibitor, m-aminobenzamidine. The trypsin-macroligand complex was then retained by using an appropriate Ultrafiltration membrane, while impurities could pass through. The bound trypsin was eluted by either arginine or benzamidine. The process also featured provision for recirculation of the eluant as well as the macroligand. It was demonstrated that this purification process could purify trypsin from the crude preparation with a yield of 77%, contaminated with only 3% of impurities. For the first time, a serious attempt has been made toward continuous purification of enzymes by the affinity Ultrafiltration technique. Besides a substantial increase in productivity, the affinity polymer could be easily reconditioned and expected to possess a long operative life. Such characteristics undoubtedly will play an important role in reducing the cost of trypsin purification.