Determination of coagulation time in whole blood containing anticoagulant by piezoelectric quartz crystal sensor

A piezoelectric quartz crystal (PQC) system possessing an adequate sensitivity to a slight change of viscosity was previously employed to monitor blood coagulation. Here, the activated partial thromboplastin time (aPTT), clotting time (CT) for platelet poor plasma (PPP), and whole blood were evaluated using PQC system, the results showed a good agreement with the aPTT results measured by optical coagulometer (OC). As a result, a good linear relationship for heparin concentration from 0 to 1 unit/ml introduced in both of the specimens could be obtained in PQC and OC systems.