基于中空多孔金纳米/石墨烯复合纳米材料的葡萄糖氧化酶直接电化学及其生物传感研究

Direct Electrochemical Behaviors of Glucose Oxidase on Hollow Porous Gold Nanoparticles/Reduced Graphene Oxide Nanocomposite and Its Biosensing Application

采用溶液相牺牲模板法制备中空多孔金纳米粒子(HPAuNPs),并将该材料与还原氧化石墨烯(rGO)复合,用于葡萄糖氧化酶(GOx)在玻碳电极(GCE)表面的有效固定,构建GOx/HPAuNPs/rGO/GCE传感界面。利用扫描和透射电镜、X射线光电子能谱、X射线衍射谱、红外光谱及电化学等方法对材料的形貌与结构,GOx的固定化过程,以及传感器的直接电化学和电催化性能进行表征。结果表明,HPAuNPs和rGO的协同作用能有效促进GOx与电极之间的直接电子转移(DET)。基于GOx/HPAuNPs/rGO/GCE对葡萄糖的良好电催化性能,该方法有效实现了对葡萄糖的高灵敏度检测,其电流响应的线性范围为0.05~7.0 mmol/L,检出限(S/N=3)为16μmol/L。该传感器具有良好的选择性、重现性及稳定性,对实际样品血清中血糖的测定结果令人满意,回收率为98.0%~103%,相对标准偏差不大于5.0%。

Hollow porous gold nanoparticles(HPAuNPs)were prepared by a simple solution phase sacrificial template method.The hollow porous gold nanoparticles/reduced graphene oxide(HPAuNPs/rGO)nanocomposite was prepared for the effective immobilization of glucose oxidase(GOx)on the surface of glassy carbon electrode(GCE).An electrochemical biosensor for detection of glucose was constructed based on GOx/HPAuNPs/rGO modified GCE.Scanning and transmission electron microscopy,X-ray photoelectron spectroscopy,X-ray diffraction spectroscopy,infrared spectroscopy and electrochemistry were used to characterize the morphology and structure of the nanomaterial,the immobilization process of GOx,and the direct electrochemical behaviors and the electrocatalytic properties of the biosensor.The results showed that the HPAuNPs/rGO nanocomposite could effectively accelerate the direct electron transfer(DET)between GOx and electrode due to the synergy effect of HPAuNPs and rGO.The modified electrode exhibited an excellent electrocatalytic property for glucose determination.The response current was proportional to the concentration of glucose in the range of 0.05-7.0 mmol/L,with a detection limit(S/N=3)of 16μmol/L.With good selectivity,reproducibility and stability,the proposed biosensor could satisfy the demands for glucose detection in real serum sample,with recoveries of 98.0%-103%,and relative standard deviations(RSDs)not more than 5.0%.