Glossary
Buffy coat
The buffy coat is the thin layer that forms between the red cells and the plasma after centrifugation. It contains most of the leukocytes and platelets in the sample. In PRP preparation it is the layer being harvested.
Figure
The buffy coat, at true scale
Figure. Drawn to proportion. The buffy coat is roughly one percent of the column, and it contains essentially everything you are trying to harvest. Nearly every difficulty in PRP preparation follows from that one fact.
In practice
In a fixed-angle rotor the buffy coat forms as a diagonal band against the tube wall, which makes a clean draw harder. In a swing-out rotor it forms flat and perpendicular to the tube.
See also
- Platelet-rich plasma (PRP)PRP is plasma with a platelet concentration above whole-blood baseline, produced by centrifuging a patient's own blood.
- Leukocyte-rich PRP (L-PRP)Leukocyte-rich PRP retains the white cells that concentrate alongside platelets in the buffy coat.
- Swing-out rotorA swing-out rotor lets tubes rotate to horizontal under load, so the layers stratify flat and perpendicular to the tube.