Figure 1.

Preparation and structure of platelet-rich fibrin (PRF). (a) shows three fractions of whole blood generated by low-speed centrifugation: platelet-poor plasma (PPP), platelet-rich fibrin (PRF), and red blood cells (RBC). At this stage, PRF and RBC have formed a gel, while the PPP fraction remains liquid. (b) Mechanical separation of the RBC fraction from the PRF fraction after decanting the PPP fraction. (c) Generation of solid PRF after liquid removal. (d) 5 μm paraffin section through solidified PRF generated in (c). The section contains three portions: (i) the cell-free fibrin clot, (ii) the buffy coat portion containing white blood cells (WBC) and platelets (PLT), and (iii) the red blood cell (RBC) portion. Note that the majority of the white blood cells and platelets are trapped in the buffy coat.