Coagulation monitoring is essential for perioperative care and thrombosis treatment. However, existing assays for coagulation monitoring have limitations such as a large footprint and complex setup. In this work, we developed a miniaturized device for point-of-care blood coagulation testing by measuring dynamic clot retraction force development during blood clotting. In this device, a blood drop was localized between a protrusion and a flexible force-sensing beam to measure clot retraction force. The beam was featured with micropillar arrays to assist the deposition of carbon nanotube films, which served as a strain sensor to achieve label-free electrical readout of clot retraction force in real time. We characterized mechanical and electrical properties of the force-sensing beam and optimized its design. We further demonstrated that this blood coagulation monitoring device could obtain results that were consistent with those using an imaging method and that the device was capable of differentiating blood samples with different coagulation profiles. Owing to its low fabrication cost, small size, and low consumption of blood samples, the blood coagulation testing device using carbon nanotube strain sensors holds great potential as a point-of-care tool for future coagulation monitoring.

中文翻译：

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基于碳纳米管应变传感器的血液牵引仪用于凝血测试

凝血监测对于围手术期护理和血栓治疗至关重要。然而，现有的凝血监测检测方法存在局限性，例如占地面积大和设置复杂。在这项工作中，我们开发了一种小型设备，通过测量凝血过程中动态凝块回缩力的发展来进行即时凝血测试。在该装置中，血滴位于突出物和柔性力传感梁之间，以测量凝块收缩力。该梁具有微柱阵列，可协助碳纳米管薄膜的沉积，该薄膜可用作应变传感器，以实现凝块收缩力的无标记实时电读出。我们表征了力传感梁的机械和电气特性并优化了其设计。我们进一步证明，这种凝血监测装置可以获得与使用成像方法一致的结果，并且该装置能够区分具有不同凝血特性的血液样本。由于其制造成本低、尺寸小、血样消耗少，使用碳纳米管应变传感器的凝血测试装置作为未来凝血监测的即时护理工具具有巨大的潜力。