Platelet rich plasma can be prepared by double centrifugation method. Whole blood in ACD anticoagulant centrifuged first at soft spin 1500 rpm for 10 minutes and then plasma with Buffy coat is separated from it leaving the red cell pelletes.The separated plasma is further then centrifuged at hard spin 3500 rpm for 20 minutes. The uper 1/3 supernatant plasma after centrifugation is platelet poor plasma and Lowe 2/3 plasma is called platelet rich plasma PRP.