基于溶胶-凝胶化的普鲁士蓝/纳米金修饰铂电极的辣根过氧化物酶传感器

采用一种新颖的方法制备了过氧化物酶生物传感器.以铂盘电极为基底,电聚合普鲁士蓝(PB)电子媒介体,并在其表面覆盖一层三维溶胶-凝胶膜,以防PB渗漏及利用其网状结构中的大量巯基吸附纳米金,最后利用纳米金静电吸附固定辣根过氧物酶制备过氧化氢传感器.通过循环伏安法对电极的修饰过程进行了表征,探讨了pH、温度对电极响应的影响.在优化的工作条件下,该传感器与H2O2浓度在7.0×10-6～6.6×10-3mol/L范围内呈线性关系,检出限为3.0×10-6mol/L.此外,该传感器具有较高的灵敏度,且能有效地消除抗坏血酸等的干扰.

A Novel Amperometric Hydrogen Peroxide Biosensor Based on PB and Nano Au as well as Sol-gel Matrixes

A novel method for fabrication of hydrogen peroxide biosensor has been developed. Prussian blue(PB), as an electron mediator, was electrochemically deposited on the platinum(Pt) electrode, then a hydrolyzed(3-mercaptopropyl)-trimethoxysilane(MPS) was coated on the PB-modified electrode to protect from leaching of PB and assemble MPS sol-gel, and then gold colloids(nano Au) were chemisorbed onto the thiol groups both inside the network and on the surface of the sol-gel. Finally, horseradish peroxidase(HRP) was absorbed onto the surface of the gold colloids. The modified processes were characterized by means of cyclic voltammetry(CV). Analytical parameters such as pH and temperature were also studied. Under the optimized conditions, linear calibration for H2O2 was obtained in the range from 7.0 × 10-6 to 6.6 × 10-3 mol/L with a detection of 3.0 × 10-6 mol/L at a signal-to-noise ratio of 3. The sensor exhibited high sensitivity, selectivity and stability.