机构地区: 宁波大学信息科学与工程学院宁波市新型功能材料及其制备科学国家重点实验室培育基地
出 处: 《分析测试学报》 2007年第3期295-299,共5页
摘 要: 用电化学方法研究了金胶表面固定酪氨酸酶(Tyr)的直接电子传递行为和该修饰电极在苯酚分析方面的应用。金胶联接在半胱胺自组装单层尾部的氨基上。在pH7.0的0.1 mol/L磷酸盐缓冲溶液中,Tyr/金胶/半胱胺修饰电极上的Tyr进行直接电子传递,产生一对氧化还原峰。固定在金胶表面的Tyr的表面覆盖度为6.6×10-10mol/cm2。不需要电子媒介体的作用,该传感器对苯酚的还原具有较好的电催化作用。苯酚测定的线性范围为2.5μmol/L^5 mmol/L,检出限为0.8μmol/L(信噪比是3)。该传感器对苯酚的测定显示了良好的重复性。在高浓度的苯酚中,此传感器表现出Michaelis-Menten行为,KMapp为3.8 mmol/L。 Tyrosinase(Tyr) molecules were immobilized on the Au colloids by using the self-assembled technique of nanometer particles. The direct electron transfer of immobilized tyrosinase (Tyr) on gold colloid and its application as a biosensor for phenol was investigated by using electrochemical methods. The Au colloids were associated with eysteamine monolayer on gold electrode surface. A couple of redox peaks attributed to the direct redox reaction of Tyr were observed at the Tyr/Au eolloid/eysteamine modified electrode in 0. 1 mol/L phosphate buffer( pH 7.0). The surface coverage of Tyr on Au colloid was about 6.6 ×10^-10 mol/cm^2. The sensor displayed an excellent eleetroeatalytie response to the reduction of phenol without the aid of electron mediator. The linear range of the calibration curve for phenol was 2.5 μmoL/L - 5 mmoL/L. The detection limit was 0.8 μmoL/L( S/N = 3 ). The sensor showed a Miehaelis - Menten behavior at high phenol concentration. The KM^app for the phenol sensor was 3.8 mmol/L.