How to Extract PRF (Platelet-Rich Fibrin)
PRF is obtained by collecting 4-8 tubes (9-10 mL each) of whole blood in special coagulation-promoting tubes (glass or silica-coated plastic), immediately centrifuging at 408 g for 12 minutes, then carefully removing the fibrin clot from the tube and separating it from the red blood cells. 1
Blood Collection Protocol
The extraction process begins with proper blood collection technique:
- Draw 4-8 tubes of 9-10 mL whole blood using special tubes that promote coagulation (glass tubes or plastic tubes with internal silica coating) 1
- Use a 21G butterfly needle preferably 1
- Immediately rotate tubes after blood draw to increase contact between blood and the inner tube surface, accelerating coagulation 1
- Titanium tubes (T-PRF) can be used as an alternative 1
Centrifugation Technique
The centrifugation process requires precise timing and technique:
- Place the first two tubes immediately in the centrifuge opposite each other for balance, then start centrifugation 1
- While centrifuge runs, collect tubes 3 and 4, stopping the centrifuge when the fourth tube is half-filled, then add these tubes promptly 1
- Centrifuge at 408 g (relative centrifugal force) measured at the area where the L-PRF clot forms (near tube center) 1
- Duration: minimum 12 minutes counting from when the last tubes are loaded 1
Critical Pitfall - Anticoagulant Medications
If the patient takes anticoagulant medication, extend centrifugation time to 18-20 minutes (counting from the last tube loaded) 1
Technical Considerations
- Account for the centrifuge radius when calculating final g force 1
- Ensure the centrifuge sits on a stable table to prevent vibration 1
- Different PRF modifications (A-PRF, A-PRF+, CGF, H-PRF) use different g forces and times 1
Clot Extraction
After centrifugation completes:
- Remove the L-PRF (fibrin) clots from tubes using tweezers 1
- Carefully separate clots from red blood cells - this step must be performed very gently 1
- Do NOT cut away the face portion (the layer just above the red blood cells) - this is the most biologically active part containing concentrated platelets and leukocytes 1
The evidence emphasizes that most platelets and leukocytes concentrate just underneath the red blood cells, making gentle separation critical to preserve the therapeutic components 1.
Creating PRF Membranes (Optional)
If membranes rather than clots are needed:
- Place L-PRF clots in a compression box for gentle gravity compression using a light metal plate and cover 1
- Membranes are ready after 5 minutes 1
- Viability lasts at least 3 hours if kept covered in the compression box to prevent drying 1
Key Quality Factors
The evidence demonstrates that centrifugation parameters significantly impact PRF structure, cellular distribution, and biomolecular content 2. Research shows that approximately 97% of platelets and >50% of leukocytes concentrate in the PRF clot when proper technique is followed 3. The protocol is reproducible as long as main production principles are respected 3.
The preparation process is not complex, but small deviations can result in unfavorable clinical outcomes 1, making strict adherence to the protocol essential.