LAUSR

Monitoring of the haemostasis status is essential for therapeutic anticoagulants, undergoing surgery, cardiovascular diseases, etc. Although the clinical values of conventional blood coagulation tests have been well demonstrated, these devices have limitations such as large and expensive equipments, excessive sample volumes, long turnaround times and difficult to miniaturization for point-of-care use. Here, we present a novel strategy to evaluate blood haemostasis using single-port Love-mode surface acoustic wave (SLSAW) sensor. The SLSAW sensor was designed as plug-and-play type unit for disposable use and operated under the harmonic resonant mode to produce frequency response to blood coagulation cascade. Comparing with quartz crystal microbalance, Lamb wave and film bulk acoustic resonator, the frequency shift of SLSAW was significantly increased, ranging from approximately 8960 kHz to 10368 kHz, which indicated enhancement of signal-to-noise ratio. To demonstrate the feasibility of the SLSAW, studies were carried out to examine the effects of temperature and clotting reagents on coagulation times and kinetics. Activated partial thromboplastin times of plasma were validated by comparing with SYSMEX CA-7000 with the correlation (R2) as 0.996. In terms of coagulation kinetics, reaction time, clot formation time, maximum frequency shift, and clot formation rate of whole blood were correlated well with corresponding parameters of standard TEG analyzer (R2 = 0.9942, 0.9868, 0.9712 and 0.9939, respectively). The SLSAW sensor, with the advantages of low cost, small size, little sample consumption (1 μL), disposable use and simple operation, is a promising tool for point-of-care diagnosis of haemostasis.