Abstract: Objective To explore the optimal centrifugation conditions for preparation of platelet-rich plasma （PRP） from different volume of whole blood.Methods Fifty-four bags of freshly collected whole blood from volunteer donors were divided into 6 groups according to centrifugal steps and centrifugal conditions,including 3 two-step （separation method A,B,and C） and three-step centrifugation groups （separation method D,E,and F）,with 3 bags of 200 ml,300 ml,and 400 ml whole blood for each group. The platelet count （PLT） and red blood cell count （RBC） of PRP in each group were determined,then PLT recovery was calculated and compared.Results Compared to three-step centrifugation groups,the PRP prepared in two-step centrifugation group had higher PLT recovery and RBC count. The highest PLT recovery in PRP from 200 ml whole blood was prepared by method A （e.g,850×g for 8 min,then 4 650×g for 6min）,300 ml whole blood by method B （e.g,1 000×g for 6 min,then 4 650×g for 6 min）,and 400ml whole blood by method C （e.g,1 220×g for 5 min,then 4 650×g for 6 min）. The RBC count of PRP in each three-step centrifugation group was decreased significantly （P<0.05）. Compared with two-step centrifugation group,the PLT recovery in three-step centrifugation group was slightly decreased.Conclusion Different centrifugation conditions should be used for preparation of PRP from different volumes of whole blood . The two-step centrifugation method is suitable for preparation of fresh PG or platelet gel,while the three-step centrifugation method is appropriate for frozen and lyophilized PRP or platelet gel.

Key words: Platelet-rich, plasma, Volunteer, donor, Preparation