Ruan C, Li Y
Department of Biological & Agricultural Engineering, University of Arkansas, Fayetteville, AR 72701, USA.
Talanta. 2001 Jul 6;54(6):1095-103. doi: 10.1016/s0039-9140(01)00378-2.
A bienzyme biosensor based on tyrosinase and horse-radish peroxidase is described in a flow injection analysis and cyclic voltammetry for measurement of phenol. Tyrosinase and horse-radish peroxidase were immobilized on the surface of a glassy carbon electrode by bovine serum albumin and glutaric dialdehyde. Phenol was oxidized by tyrosinase and horse-radish peroxidase via catechol to o-quinone in the presence of oxygen and hydrogen peroxide. The o-quinone was reduced to produce catechol (the substrate recycling) on the electrode surface. The enhanced sensitivity of the bienzyme electrode to phenol was observed in the flow injection system comparing with tyrosinase and horse-radish peroxidase monoenzyme electrodes. The mechanisms for enhanced amperometric response to phenol of bienzyme electrode were discussed. The biosensor was used to detect alkaline phosphatase (ALP). A detection limit of 1.4x10(-15) M ALP (140 zmol/100 mul) was obtained after 1 h incubation with phenyl phosphate.
本文描述了一种基于酪氨酸酶和辣根过氧化物酶的双酶生物传感器，用于流动注射分析和循环伏安法测定苯酚。酪氨酸酶和辣根过氧化物酶通过牛血清白蛋白和戊二醛固定在玻碳电极表面。在氧气和过氧化氢存在下，苯酚被酪氨酸酶和辣根过氧化物酶通过邻苯二酚氧化为邻苯醌。邻苯醌在电极表面被还原生成邻苯二酚（底物循环）。与酪氨酸酶和辣根过氧化物酶单酶电极相比，在流动注射系统中观察到双酶电极对苯酚的灵敏度增强。讨论了双酶电极对苯酚增强安培响应的机制。该生物传感器用于检测碱性磷酸酶（ALP）。与磷酸苯酯孵育1小时后，获得了1.4×10⁻¹⁵ M ALP（140 zmol/100 μl）的检测限。
