Acoustic tweezing coagulometry: Noncontact coagulation analysis of a drop of blood

Acoustic tweezing coagulometry provides containerless coagulation analysis using a small, 4–6 microliter drop of blood. It operates in two regimes: integrated quasi-static acoustic tweezing thromboelastometry (i-QATT), which measures clot firmness and turbidity, and acoustic tweezing spectroscopy (ATS) assessing clot viscoelasticity. In this work, these two techniques were clinically assessed on venous whole blood (WB) and platelet-poor plasma (PPP) samples from non-smoking healthy adult volunteers, smoking adult volunteers, pediatric patients with hemophilia A, and pediatric patients on ECMO/hemodialysis. The results of this study indicate that the values of i-QATT parameters MCF (maximum clot firmness), CIT (clot initiation time), and RT (reaction time) were strongly correlated with fibrinogen concentration and lab values obtained by gold-standard plasma tests (aPTT, PT) and viscoelastic hemostatic assays (ROTEM). Reference ranges for these parameters ruled out abnormal coagulation caused by factor deficiency, heparin, antiplatelet agents (Cytochalasin-D), or fibrinogen spiking. In the ATS technique, RT measured from the WB viscosity data demonstrated a strong correlation with plasma PT/aPTT. Linear correlation was obtained between the WB MCF output and the fibrinogen concentration. Acoustic tweezing coagulometry enables comprehensive drop-of-blood coagulation analysis that rapidly detects hypo- and hyper-coagulable states and measures PT, aPTT, and fibrinogen in WB or hemolyzed plasma samples.