基于壳聚糖/碳纳米管/石墨烯/铁氰化镍纳米复合材料构建的电化学适体传感器用于凝血酶的检测

摘要

In this paper, we successfully fabricated a highly sensitive label-free electrochemical aptasensor for thrombin (TB) detection. The nanocomposites composed with chitosan, carbon nanotubes, graphene and nickel hexacyanoferrate (CS-CNTs-Gra-FP) was used as a matrix for thrombin aptamer (TBA) immobilization. The employment of CS-CNTs-Gra-FP nanocomposites and nano-Au not only enhanced the surface area of the electrode with increased FP immobilization, but also enhanced the electron transfer, which further effectively improved the sensitivity of this proposed aptasensor. The resulted aptasensor exhibited good current response to thrombin with a wide linear range extended from 0.01 nmol/L to 30 nmol/L, and the detection limit was 0.003 nmol/L. Furthermore, the prepared aptasensor had great advantages in simplification, rapidity, stability and selectivity.%该文利用壳聚糖/碳纳米管/石墨烯/铁氰化镍（CS-CNTs-Gra-FP）纳米复合材料作为电化学探针FP的固载基质，并采用纳米金（nano-Au）吸附凝血酶适体（TBA），构建了一个高灵敏、无标记的电化学适体传感器。其中CS-CNTs-Gra-FP纳米复合材料和nano-Au的引入不仅增大了电极的比表面积、增强了电子的传输速率，也增加了电活性物质铁氰化镍（FP）的固载量，从而极大地提高了该传感器的灵敏度。实验结果表明，该传感器对凝血酶测定具有良好的线性关系，其线性范围是为0.01 nmol/L~30 nmol/L，检测下限为0.003 nmol/L。此外，该传感器制备简单，操作简便，稳定性好，特异性强。