基于1T-WS_(2)@AuNPs复合材料的白芸豆酯酶电化学生物传感器构建及其杀螟硫磷检测应用

Fabrication of a White Kidney Bean Esterase-Based Electrochemical Biosensor Using 1T-phase Tungsten Disulfide/Gold Nanoparticles(1T-WS_(2)@AuNPs)and Its Application in the Detection of Fenitrothion

通过简单的自组装方法制备了由1T相二硫化钨纳米片(1T-WS_(2))和纳米金(AuNPs)组成的新型纳米复合材料1T相二硫化钨/纳米金(1T-WS_(2)@AuNPs)。利用其优异的理化性能对传感信号增敏,与来源于白芸豆的酯酶,共同构建了一种基于1T-WS_(2)@AuNPs纳米复合材料的白芸豆酯酶电化学生物传感器,用于有机磷农药杀螟硫磷的低成本、高灵敏检测。采用扫描电子显微镜、透射电子显微镜以及X射线光电子能谱对所制材料的形貌和组成进行表征。对底液pH值、复合材料负载量及酶负载量等电化学检测条件进行考察。在最优条件下,CS/KbE/1T-WS_(2)@AuNPs/GCE传感器对杀螟硫磷的线性检测范围为0.1~2000μg/L,标准曲线的相关系数为0.992,检出限为0.04μg/L。此传感器具有良好的重复性、稳定性与抗干扰能力。将其用于实际农产品中杀螟硫磷的检测,回收率为96.16%~109.60%,表明所建传感器在有机磷农药检测方面具有潜在应用价值。

A novel nanocomposite composed of 1T-phase tungsten disulfide nanosheets(1T-WS_(2))and gold nanoparticles(AuNPs)was prepared by a simple self-assembly method and was used to construct a white kidney bean esterase based electrochemical biosensor for the low-cost and highly sensitive detection of fenitrothion,which could enhance the sensor’s sensitivity by virtue of its excellent physicochemical properties.The morphology and composition of the prepared material were characterized by scanning electron microscopy(SEM),transmission electron microscopy(TEM)and X-ray photoelectron spectroscopy(XPS).Working parameters such as pH,composite loading and enzyme loading were investigated.Under the optimum conditions,the linear range was 0.1-2000 μg/L,the correlation coefficient of the standard curve was 0.992 and the limit of detection(LOD)was 0.04 μg/L.In addition,the proposed biosensor showed satisfactory repeatability,stability and selectivity.The biosensor has been applied to the analysis of fenitrothion in real agriculture samples with recoveries of 96.16%-109.60%,indicating that the biosensor has potential application in the detection of organophosphorus pesticides.