University of Michigan laboratory

Much of the research in the University of Michigan laboratories has been done with the Hi-Sep 70, a vinyl plastic membrane [Graver Water Conditioning Co., New York, N. Y.] which has an effective pore size of 70 A units and is not subject to bacterial degradation. Unfortunately this material is somewhat brittle and tends to crack at points where fiexure takes place in a dialysis frame. It also tends to change pore size when sterilized in an autoclave. 

---