Preparation of concentrated platelet suspensions by dehydration against polyethyleneglycol 20,000

Gel filtered platelet suspensions were concentrated by repeated dehydration against polyethyleneglycol 20,000 followed by dialysis against slightly hypotonic buffer. This method increased the platelet concentration 2-3 times with a recovery of 80-100%. The final cell suspension closely resembled the original platelet rich plasma as tested by a number of platelet tests.