Amperometric biosensor for hypoxanthine based on immobilized xanthine oxidase on nanocrystal gold-carbon paste electrodes
Amperometric biosensor for hypoxanthine based on immobilized xanthine oxidase on nanocrystal gold-carbon paste electrodes
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DOI：
10.1016/j.snb.2005.03.001
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发表时间：
2006-01-17
影响因子：
8.4
通讯作者：
Pingarrón, JM
中科院分区：
文献类型：
--
作者：
Agüi, L;Manso, J;Pingarrón, JM
报道了一种基于电沉积纳米金（nAu）修饰碳糊电极（CPE）的黄嘌呤氧化酶（XOD）生物传感器的制备及其对次黄嘌呤（Hx）的安培测定。不同的XOD生物传感器的配置进行了评估和比较，通过固定XOD到未改性CPE和生物传感器制备的玻碳电极和金盘电极与电沉积金改性的电极。XOD-nAu-CPE中的酶是通过戊二醛（GA）和BSA交联固定的，表现出最高的Hx安培信号。虽然Hx检测通常在相对于Ag/AgCl约+600 mV的电位值下进行，但GA-BSA-XOD-nAu-CPE允许在0.00 V下进行该检测，从而最大限度地减少了来自电化学可氧化物质（如抗坏血酸）的潜在干扰。优化了制备生物传感器的实验参数。Hx的校准图是用在+600 mV和0.00 V下工作的生物传感器构建的。使用后一个电位值获得的Hx的检测限为2.2 x 10（-7）mol l（-1），与文献中报道的在更极端电位下工作的其他生物传感器设计的最佳检测限相似。通过测定沙丁鱼和鸡肉中的Hx，证明了该生物传感器用于分析真实的样品的有用性。(c)2005 Elsevier B. V.保留所有权利。
The preparation and performance of a xanthine oxidase (XOD) biosensor, based on a carbon paste electrode (CPE) modified with electrodeposited gold nanoparticles (nAu), for the amperometric determination of hypoxanthine (Hx) is reported. Different XOD biosensor configurations were evaluated and compared with electrodes constructed by immobilizing XOD onto unmodified CPE and with biosensors prepared using glassy carbon electrodes and gold disk electrodes modified with electrodeposited gold. The XOD-nAu-CPE in which the enzyme was immobilized by cross-linking with glutaraldehyde (GA) and BSA exhibited the highest amperometric signal for Hx. Although Hx detection is usually carried out at potential values of around +600 mV versus Ag/AgCl, the GA-BSA-XOD-nAu-CPE allowed this detection to be carried out at 0.00 V, thus minimizing potential interferences from electrochemically oxidizable substances such as ascorbic acid. Experimental variables concerning the biosensor preparation were optimized. Calibration plots for Hx were constructed with the biosensor operating at +600 mV and at 0.00 V. The detection limit for Hx, 2.2 x 10(-7) mol l(-1) obtained using the latter potential value is similar to the best detection limits reported in the literature with other biosensor designs working at much more extreme potentials. The usefulness of the biosensor for the analysis of real samples was demonstrated by determining Hx in sardines and chicken meat. (c) 2005 Elsevier B.V. All rights reserved.