The PRP serum was prepared with two rounds of differential centrifugation. All samples underwent the same initial centrifugation or ‘soft spin’. The samples were spun at 250g for 10 minutes which isolated constituent blood particles by weight. Red blood cells, the heaviest blood elements, sank to the bottom of the vacuum tubes, followed by the buffy coat (which contains leukocytes and platelets) and topped with the remaining blood plasma (platelet poor plasma- PPP).
Next, the platelet poor plasma and buffy coat were aspirated into a new, sterile vacuum tube for secondary centrifugation. Dual centrifugation has become common practice and is used to further increase platelet concentration. During the force of the second centrifugation, more platelets precipitate out of the PPP. In this study researchers aimed to evaluate the effect of varying the force of the secondary spin on final platelet concentration. The samples of each participant were divided into 6 groups according to the force applied during secondary centrifugation from 300g up to 2000g for 10 minutes (with increments at 500g, 750g, 1000g, & 1500g).
ANOVA analysis revealed that platelet concentration increased with increasing g forces. There was no significant difference between the 300 & 500g groups, but platelet concentration increased significantly between 500g, 750g & 1000g centrifugation, and the average platelet count leveled off in the higher g-force groups with no significant increase from 1000-2000g.