Department of Chemistry, University of Shahid Bahonar Kerman, Kerman, Iran; Young Research Society, Shahid Bahonar University of Kerman, Kerman, Iran.
Department of Chemistry, University of Shahid Bahonar Kerman, Kerman, Iran.
Bioelectrochemistry. 2019 Dec;130:107322. doi: 10.1016/j.bioelechem.2019.06.007. Epub 2019 Jun 25.
In this work, a selective and simple electrochemical aptasensor was developed for the detection of activated protein C by employing methylene blue (MB) as a redox indicator. An activated protein C aptamer (APC-apt) was covalently immobilized on the surface of a carbon paste electrode modified with gold nanoparticle - chitosan /graphene paste (AuNPs-Chi/Gr). The AuNPs-Chi/Gr paste increased electrochemical peak current and immobilized the aptamer on the electrode surface. The process of aptasensor construction and successful immobilization of the aptamer on the electrode surface was confirmed by electrochemical cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Differential pulse voltammetry (DPV) was used to determine the methylene blue peak current. By replacing APC instead of MB at the electrode surface, the cathodic current of the MB decreases, and this decrease corresponds to the APC concentration. Under optimum conditions, the APC concentration was detected in the range from of 0.1 ng·mL to 40 μg·mL with a relatively low detection limit of 0.073 ng·mL. This method was then applied to the determination of APC in human serum samples. The results revealed that this strategy can be used to measure other proteins in biological samples.
在这项工作中，通过使用亚甲基蓝 (MB) 作为氧化还原指示剂，开发了一种用于检测活化蛋白 C 的选择性和简单的电化学适体传感器。将活化蛋白 C 适体 (APC-apt) 通过共价键固定在金纳米粒子-壳聚糖/石墨烯糊 (AuNPs-Chi/Gr) 修饰的碳糊电极表面。AuNPs-Chi/Gr 糊增加了电化学峰电流并将适体固定在电极表面上。通过电化学循环伏安法 (CV) 和电化学阻抗谱 (EIS) 证实了适体传感器的构建过程和适体在电极表面上的成功固定。差分脉冲伏安法 (DPV) 用于测定亚甲基蓝峰电流。通过在电极表面用 APC 代替 MB，MB 的阴极电流减小，这种减小与 APC 浓度相对应。在最佳条件下，APC 的浓度在 0.1ng·mL 至 40μg·mL 的范围内进行检测，检测限相对较低，为 0.073ng·mL。然后将该方法应用于人血清样品中 APC 的测定。结果表明，该策略可用于测量生物样品中的其他蛋白质。
