Lee Ai-Cheng, Liu Guodong, Heng Chew-Kiat, Tan Swee-Ngin, Lim Tit-Meng, Lin Yuehe
Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 117543.
Electroanalysis. 2008 Aug 5;20(18):2040. doi: 10.1002/elan.200804287.
A rapid, simple and sensitive electrochemical assay of horseradish peroxidase (HRP) performed on disposable screen-printed carbon electrode was developed. HRP activities were monitored by square-wave voltammetric (SWV) measuring the electroactive enzymatic product in the presence of o-aminophenol and hydrogen peroxide substrate solution. SWV analysis demonstrated a greater sensitivity and shorter analysis time than the widely used amperometric and differential-pulsed voltammetric methods. The voltammetric characteristics of substrate and enzymatic product as well as the parameters of SWV analysis were optimized. Under optimized conditions, a linear response for HRP from 0.003 - 0.1 U/mL and a detection limit of 0.002 U/mL (1.25×10(-15) mol in 25 μL) were obtained with a good precision (RSD = 8%; n = 6). This rapid and sensitive HRP assay with microliters-assay volume could be readily integrated to portable devices and point-of-care (POC) diagnosis applications.
开发了一种在一次性丝网印刷碳电极上对辣根过氧化物酶（HRP）进行快速、简单且灵敏的电化学检测方法。通过方波伏安法（SWV）在邻氨基酚和过氧化氢底物溶液存在的情况下测量电活性酶产物来监测HRP活性。与广泛使用的安培法和差分脉冲伏安法相比，SWV分析显示出更高的灵敏度和更短的分析时间。对底物和酶产物的伏安特性以及SWV分析参数进行了优化。在优化条件下，获得了HRP在0.003 - 0.1 U/mL范围内的线性响应以及0.002 U/mL（25 μL中为1.25×10(-15) mol）的检测限，精密度良好（RSD = 8%；n = 6）。这种具有微升检测体积的快速灵敏的HRP检测方法可以很容易地集成到便携式设备和即时检测（POC）诊断应用中。
