Abstract
Platelet concentrates (PC) is classified into six categories, depending on their contents: leucocyte- poor or pure
platelet- rich plasma(P- PRP),leucocyte- and platelet- rich plasma (L- PRP),leucocyte and platelet poor or pure
plasma(L- PPP), leucocyte- poor or pure platelet- rich fibrin(P- PRF)concentrated, leucocyte- and platelet- rich
fibrin (L- PRF)concentrated and leucocyte and platelet poor or pure fibrin(L- PPF）concentrated.
We obtained two types of PRPs, red- PRP and yellow- PRP, named according to their color, from whole
blood without anti- coagulant chemical agent, using centrifugation (400g x 10 min.) in plastic tube made of
polypropylene, delaying clotting time. The red- PRP included the collecting from the plasma layer with buffy
coat. On the other hand, the yellow- PRP included the collecting from the plasma layer without buffy coat.
The mean counts of platelets between the red- PRP and the yellow- PRP were not significantly different,
although they were about 1.43- and 1.28- fold higher than in whole blood, respectively. Although the red- PRP
contained 70% of leucocytes compared with whole blood, the yellow- PRP kept merely 10% of leucocytes
compared with whole blood and completely lost neutrophil fraction. These results indicate that the red- PRP
and yellow- PRP are equivalent to L- PRP and P- PRP, respectively.
We also obtained two types of PRP gel, red- PRP gel and yellow- PRP gel were fabricated using centrifugation
of red- and yellow- PRP at 650g for 10min. in glass tubes. Histological examination of the red- PRP gel showed
that it consisted of three layers from the bottom to the top, the mixture of leucocytes and erythrocytes,
platelets and compressed fibrin. Histological examination of the yellow- PRP gel showed that it consisted of two
layers, platelets at bottom and compressed fibrin at top. In the yellow- PRP gel, we didn’t find the mixture of
leucocytes and erythrocytes. These results indicate that the red- PRP gel and yellow- PRP gel are equivalent
to L- PRF and P- PRF, respectively.
The manipulations of these plastic tube and glass tube method could lead to the easy generation of the
various sort of PC for the effective and safety clinical applications as a point- of- care method.
