基于ZnO纳米线的螺旋线形跨尺度葡萄糖传感器

摘要

In this paper, a spirally hierarchical structure-based enzymatic glucose sensor was constructed and characterized. An Au fiber of diameter 30 μm was spiraled on an optical fiber core of diameter 125 μm, for-ming a cylindrical spiral. ZnO nanowires were hydrothermally synthesized on the surface of the cylindrical spi-ral, generating a spirally hierarchical structure. Glucose oxidase( GOD) was physically adsorbed on the ZnO nanowires, producing the working electrode of the glucose sensor. Based on micrographs of scanning electron microscopy( SEM) and operators of filtration, line edge detection and fitting of MatLab software, the surface morphology of the spirally hierarchical structure and the adsorption of GOD of activity 50 units/mg on its sur-face were qualitatively and quantitatively characterized, and the effect of the surface morphology of this non-Gaussian rough surface on GOD adsorption also was briefly investigated. Based on the three-electrode system, cyclic voltammetry and amperometric response were employed to evaluate the performance of 12 glucose sen-sors. The sensitivity, the linear range, Michaelis-Menten constant and the detection limit of these 12 glucose sensors were determined to be (1. 410±0. 665) μA·L/(mmol·cm2), 0 -(4. 292±0. 652) mmol/L, (3. 571±1. 280) mmol/L, and (14. 085±8. 393) μmol/L, respectively. With GOD of higher activity used, a glucose sensor with better performance can be constructed. This three-electrode system-based glucose sensor with a spirally hierarchical structure can be employed to detect concentrations of uric acid, urea, cholesterol, hydroperoxide and phenol in medicine, biology, food industry and environmental monitoring domain.%制备了一种基于螺旋线形跨尺度结构的酶传感器,并对该传感器进行了表征和性能测试.将准30μm键合Au丝以螺旋线方式手工缠绕在准125μm光纤纤芯上,在该Au螺旋线上用水浴法合成ZnO纳米线,得到螺旋线形跨尺度结构；在ZnO纳米线上物理吸附葡萄糖氧化酶( GOD),制备了葡萄糖传感器工作电极.利用扫描电子显微镜( SEM)图像和MatLab图像处理算子分别对螺旋线形跨尺度结构表面形貌及其上活力为50 units/mg的GOD吸附效果进行了定性和定量表征,分析了非高斯粗糙表面与GOD吸附效果的影响关系.基于三电极体系采用循环伏安法和计时安培法测试了制备的12个工作电极的性能,测得该类传感器的灵敏度为(1.410依0.665)μA·L/(mmol·cm2),线性范围为0~(4.292依0.652) mmol/L, Michaelis-Menten常数为(3.571依1.280) mmol/L,检出限为(14.085依8.393)μmol/L.使用活力更高的GOD可以得到性能更好的螺旋线形跨尺度葡萄糖传感器.该类传感器可广泛应用于医药、生物、食品加工及环境监测领域中尿酸、尿素、胆固醇、过氧化氢和苯酚等的检测.