PRP quality control means knowing, for every preparation, what you are about to inject: the platelet concentration, how it compares with the patient’s baseline, and whether the preparation went as planned. Most practices still rely on the nominal concentration factor of their kit. This page describes a simple PRP quality control routine based on a measured platelet count, and how the PC100 fits into it.

Why PRP quality control matters

Clinical results with PRP vary widely between studies and between patients, and one of the recognised reasons is that the product itself varies. The platelet concentration of PRP depends on the patient’s baseline platelet count, the anticoagulant and blood volume, the centrifugation speed and time, and how the plasma fractions are separated. Published comparisons of commercial PRP systems show platelet concentration factors ranging from below 1 (a “PRP” with fewer platelets than whole blood) to more than 8. Without a measurement, none of this is visible at the point of treatment.

A measured platelet count turns PRP from a procedure into a defined product. It allows you to state the dose, to compare treatments, to notice a failed preparation before it is used and to document what was done.

A practical PRP quality control routine

Baseline count: take 20 µl of the patient’s whole blood before preparation and count it. Whole-blood platelet counts normally fall between 150 and 400 platelets per nanolitre; the PC100 covers 20-600 plt/nL.
Prepare the PRP according to your kit or protocol.
Final count: take 10 µl of the finished PRP and count it. The PC100 is validated for 250-3600 plt/nL, which covers the concentrations produced by common PRP systems.
Calculate the concentration factor (final ÷ baseline) and the total platelet dose (concentration × injected volume).
Decide and document: inject, adjust the volume, or re-prepare if the result is outside your target; file the printed or exported PC100 report with the treatment record.

The whole routine adds about 10 minutes and two disposable kits to a treatment, and it can be performed by practice staff after a short introduction. See how to make a platelet count in 4 steps.

What to look for in the results

Observation	Possible cause	Action
Final concentration far below the kit’s nominal factor	Insufficient centrifugation, too much plasma removed, low baseline count	Check protocol; consider a second spin or a different volume
Final concentration much higher than expected	Very high baseline, small PRP volume	Adjust injected volume to the intended dose
High CV between the two counting chambers	Platelet clumps, air bubbles in the slide, incomplete mixing	Mix gently, refill a new slide, repeat the count
Result outside the validated range	Extremely concentrated PRP or platelet-poor plasma	Dilute and repeat, or re-prepare

The PC100 reports the platelet concentration of both chambers of the counting slide and the CV between them, which gives an immediate plausibility check on each count. Every report also contains an image of each counted position. See PC100 platelet count results explained.

Why the PC100 for PRP quality control

Validated for PRP (250-3600 plt/nL) and whole blood (20-600 plt/nL) against Sysmex analyzers in a peer-reviewed study in Thrombosis Journal.
Point of care: result in about 4 minutes on any desk, no laboratory, no sample transport.
No calibration and no cleaning: all parts in contact with blood are single-use.
Traceable: printable and exportable report with counting details and images.
CE-marked class A IVD, manufactured under ISO 13485.

Read more on the PRP platelet counter page and on the platelet count in PRP.