Effects of speed and time of centrifugation and time of freezing on the amount of produced microparticles from concentrates platelet

The main method of separating platelet microparticles (PMP) is based on the centrifugation speed and time. Due to the high cost of determining the number of PMP via micro-particles (micro bead) and also the necessity of using an expensive device such as a flow cytometer, it seems that Bradford method would be rather an inexpensive, fast and efficient way to determine the concentration of PMP. Therefore, in this study the effect of different factors, such as speed and time of centrifugation and time of freezing on the concentration of PMP in the platelet concentrates bags was studied.
We studied two different speeds of centrifugation for separating PRP. In the first protocol for preparation of PRP, the platelet bags were centrifuged at 1500g for 15min and in the second protocol; they were centrifuged at 5000g for the same duration. To evaluate the effect of time, microparticles were separated in 16000g for 20 and 2 min. To determine the concentration of PMP, Bradford method was used. To evaluation the effect of freezing, the PRP was prepared at 300g for 20 min, and then it was freezed in -80˚c for five days. Flow cytometery analysis was performed for microparticles identification.
PMP concentrates with the 1500g centrifugation speed showed higher concentration (P The result of this study showed that the reduction of centrifugation speed could produce higher levels of the microparticles. In addition, the time of separation in the final stage had no significant effect on PMP isolation. Freezing could lead to higher PMP concentration.