ACS Sens. 2018 Mar 23;3(3):670-676. doi: 10.1021/acssensors.7b00971. Epub 2018 Feb 27.
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.
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，例如占地面积大且设置复杂。在这项工作中，我们通过测量血液凝固过程中动态血凝块回缩力的发展，开发了一种用于即时凝血检测的微型化设备。在该设备中，将血滴定位在凸起和柔性力传感梁之间，以测量血凝块回缩力。该梁具有微柱阵列，以辅助碳纳米管薄膜的沉积，碳纳米管薄膜用作应变传感器，可实时实现无标记的血凝块回缩力电读取。我们对力传感梁的机械和电气特性进行了表征，并对其设计进行了优化。我们进一步证明，这种凝血监测设备可以获得与使用成像方法一致的结果，并且该设备能够区分具有不同凝血特征的血液样本。由于其制造成本低、体积小且对血液样本的消耗低，使用碳纳米管应变传感器的血液凝血检测设备有望成为未来凝血监测的即时护理工具。
