石墨烯(Graphene, GR)作为一种革命性的材料具有优异的理化特性, 其优异的导电性对凝血电化学传感器的研制极其重要。目前大型凝血检测仪器操作复杂、耗时较长, 且对活化部分凝血活酶时间(APTT)指标的POCT检测较少。针对这一现状, 设计制作一种可以用于APTT指标检测, 基于丝网印刷技术的GR改性增强型电化学传感器十分必要。通过凝血酶切割凝血酶底物实验验证计时电流法检测活化部分凝血活酶时间原理的可行性, 测量血浆活化部分凝血活酶时间参数, 同时使用SYSMEX CS 5100光学凝血仪验证测量结果。实验表明, 丝网印刷GR改性电极具有良好的一致性, 其阻抗测试变异系数为2.71%。凝血酶实验中, GR改性电化学传感器检测的电流响应强度较改性前的电化学传感器增加了16±1%, 重复出峰时间和峰值电流变异系数分别为3.29%和3.13%。选取3组血样APTT值, 能够清晰地显示出区分度, 且每组APTT重复实验的出峰时间变异系数分别为3.20%, 3.25%和2.84%, 实验结果与医院的临床结果线性拟合决定系数R2为0.978。GR改性增强型电化学传感器在APTT测试中显示出了较好地重复性, 具有在多种场合下进行即时检测的潜力。

Graphene (GR) has excellent physical and chemical properties as a revolutionary material, and its excellent electrical conductivity is critical in developing coagulation electrochemical sensors. Currently, large coagulation testing instruments are complicated to operate and time-consuming, and few point-of-care tests exist for activated partial thromboplastin time (APTT) indicators. To solve this problem, designing and manufacturing a GR-modified electrochemical sensor based on screen-printing technology, which can be used for APTT index detection, is necessary. In this study, the feasibility of chronoamperometry to detect the time principle of activated partial thromboplastin was verified by a thrombin-cleaving thrombin substrate assay. The plasma-activated partial thromboplastin time parameter was measured, and the measurement results were verified using a SYSMEX CS 5100 optical coagulation instrument. The experiments showed that the screen-printed GR-modified electrode had good consistency, and its impedance test coefficient of variation is 2.71%. In the thrombin experiment, the current response intensity of the GR-modified electrochemical sensor was increased by 16 ± 1% as compared to the electrochemical sensor before modification, and the repeated peak time and peak current coefficient of variation are 3.29% and 3.13%, respectively. The APTT values of the three groups of blood samples were selected to show clearly the degree of discrimination, and the peak time variation coefficients of the three groups of APTT repeat experiments are 3.20%, 3.25%, and 2.84%, respectively. The experimental results are linearly fitted with the clinical results of the hospital. R2 is 0.978. The GR-modified enhanced electrochemical sensor showed good repeatability in the APTT test and thus has the potential for immediate detection in a variety of situations.