Aim: The purpose of this study was to obtain data concerning growth factor release
within liquid and solid platelet-rich fibrin (PRF) matrices and to estimate the amount
of potential interindividual variations as a basis for further preclinical and clinical
trials. Therefore, we aimed to determine possible differences in the release of growth
factors between liquid and solid PRF. Materials and Methods: Blood samples obtained
from four subjects were processed to both liquid and solid PRF matrices using a standard
centrifugation protocol. Five growth factors (vascular endothelial growth factor,
VEGF; epidermal growth factor, EGF; platelet-derived growth factor-BB, PDGF-BB; transforming
growth factor-β1, TGF-β1; and matrix metallopeptidase 9, MMP-9) have been evaluated
at six time points by ELISA over a total observation period of 10 days (1 h, 7 h,
1 d, 2 d, 7 d, and 10 d). Results: Growth factor release could be measured in all
samples at each time point. Comparing liquid and solid PRF matrices, no significant
differences were detected (p > 0.05). The mean release of VEGF, TGFβ-1, PDGF-BB, and
MMP-9 raised to a peak at time point five (day 7) in both liquid and solid PRF matrices.
VEGF release was lower in liquid PRF than in solid PRF, whereas those of PDGF-BB and
MMP-9 were higher in liquid PRF than in solid PRF at all time points. EGF had its
peak release already at time point two after 7 h in liquid and solid matrices (hour
7 EGF solid: mean = 180 pg/mL, SD = 81; EGF liquid: mean = 218 pg/mL, SD = 64), declined
rapidly until day 2, and had a second slight peak on day 7 in both groups (day 7 EGF
solid: mean = 182 pg/mL, SD = 189; EGF liquid: mean = 81 pg/mL, SD = 70). Conclusions:
This study detected growth factor release within liquid and solid PRF matrices with
little variations. Further preclinical trials are needed to precisely analyze the
growth factor release in larger samples and to better understand their effects on
wound healing in different clinical indications.
