肌苷酶电极生物传感器

An Enzyme Electrode Biosensor for Inosine Determination

摘要:

为了构建肌苷酶电极生物传感器, 以固定化核苷磷酸化酶 (EC 2.4.2.1)、黄嘌呤氧化酶 (EC 1.2.3.2)与过氧化氢电极组成电流型酶电极生物传感器, 用于检测肌苷片中的肌苷, 其输出电流可达500 nA。结果发现, 肌苷测定的线性范围为1~268 mg/L, 精度: RSD小于0.14%, 响应时间: 60 s, 使用寿命大于25 d, 实际测定肌苷片中肌苷含量回收率: 100.8%。由此表明: 采用双酶电极法测定肌苷片中的肌苷含量, 由于酶促反应专一性高、样品不需分离直接进样分析、处理条件温和、反应时间短暂因而结果较为可靠。

Abstract:

An enzyme electrode biosensor was used for the amperometric determination of inosine in its tablets by co-immobilizing nucleoside phosporylase and xanthine oxidase on a hydrogen peroxide electrode. As a fundamental electrode the hydrogen peroxide electrode has an advantage of stability in analysis compared with the O2 electrode. The enzyme electrode showed a linear response to inosine in the range of 1~268 mg/L with a response of 60 seconds under a sample injection volume of 25 mL. Based on the enzyme electrode, inosine solutions were determined with an average recover rate of 100.8% and a relative standard deviation (RSD) of less than 0.14% in 20 assays. The lifetime of the enzyme electrode was relative long and could be used continuously at 25oC for 25 days. These results demonstrated that the enzyme electrode biosensor could be used to determine inosine and its derivatives specifically, rapidly, conveniently and economically.