Use of magnetoelastic sensors for quantifying platelet aggregation I: Whole blood and platelet rich plasma

We report the use of magnetoelastic sensors for studying platelet aggregation in fresh bovine blood and platelet rich plasma. The resonance amplitude of gravimetric magnetoelastic sensors immersed in blood/plasma samples mixed with EDTA, ADP, and Collagen are measured as a function of time. The sensors immersed in ADP and Collagen activated blood show a greater change of resonance amplitude compared to the sensor in EDTA mixed blood. Such a response of the magnetoleastic sensors in ADP and Collagen activated blood is attributed to a higher mass loading effect on the sensor surfaces caused by settling of the aggregated platelets. Platelet aggregation in ADP activated blood is confirmed by platelet count measurements carried out with a standard hematology analyzer programmed for cow blood. The sensors detect aggregation of platelets in platelet rich plasma, but with a smaller change of amplitude attributed to reduced mass loading. This work establishes the utility of the magnetoelastic sensing technology as a simple, portable, and cost effective tool for platelet aggregation studies of whole blood as well as platelet rich plasma.