Effect of freeze-drying process on collagen-activated platelet-rich plasma into platelet derived growth factor-AB level

Platelet-rich plasma (PRP) is a choice of regenerative material because of its superiority, that is a high growth factor content. However, one of the disadvantages of PRP should be used immediately after preparation. It is most effective if PRP can be made and stored, so that it can use multiple times in different treatment times. Freeze-drying is known as a way to preserve food and drugs that can maintain material stability in the long term. Storage of PRP by the freeze-drying process allows the maintenance of growth factors as an important substance contained therein. In this study, we used collagen as an activator material that stimulates of growth factor's release. Platelet-derived growth factor-AB (PDGF-AB) is a growth factor contained in PRP that stimulates fibroblasts, chemotaxis, stimulation of TGF-β growth factor, collagen production, and increased protein synthesis. The purpose of this study was to assess whether growth factor content, especially PDGF-AB, would be preserved after the freeze-drying process. PRP was produced from the human's peripheral blood by two centrifugations, activated by collagen, then divided into 3 groups: collagen-activated PRP which followed by the freeze-drying process (FD PRP+C), collagen-activated PRP without freeze-drying (PRP+C), and fresh PRP as a baseline. The level of PDGF-AB was measured using the ELISA method. The data were analysed using one-way ANOVA. The results showed that there were significant differences between FD PRP+C with other groups. The PDGF-AB of FD PRP+C group was the highest level than others.