State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
Sensors (Basel). 2017 Sep 27;17(10):2214. doi: 10.3390/s17102214.
In this paper, the performance of a zinc oxide (ZnO) nanorod-based enzymatic glucose sensor was enhanced with silver (Ag)-doped ZnO (ZnO-Ag) nanorods. The effect of the doped Ag on the surface morphologies, wettability, and electron transfer capability of the ZnO-Ag nanorods, as well as the catalytic character of glucose oxidase (GOx) and the performance of the glucose sensor was investigated. The results indicate that the doped Ag slightly weakens the surface roughness and hydrophilicity of the ZnO-Ag nanorods, but remarkably increases their electron transfer ability and enhances the catalytic character of GOx. Consequently, the combined effects of the above influencing factors lead to a notable improvement of the performance of the glucose sensor, that is, the sensitivity increases and the detection limit decreases. The optimal amount of the doped Ag is determined to be 2 mM, and the corresponding glucose sensor exhibits a sensitivity of 3.85 μA/(mM·cm²), detection limit of 1.5 μM, linear range of 1.5 × 10-6.5 mM, and Michaelis-Menten constant of 3.87 mM. Moreover, the glucose sensor shows excellent selectivity to urea, ascorbic acid, and uric acid, in addition to displaying good storage stability. These results demonstrate that ZnO-Ag nanorods are promising matrix materials for the construction of other enzymatic biosensors.
本文通过在氧化锌（ZnO）纳米棒上掺杂银（Ag），提高了基于 ZnO 纳米棒的酶葡萄糖传感器的性能。研究了掺杂 Ag 对 ZnO-Ag 纳米棒表面形貌、润湿性和电子转移能力的影响，以及葡萄糖氧化酶（GOx）的催化特性和葡萄糖传感器的性能。结果表明，掺杂 Ag 略微减弱了 ZnO-Ag 纳米棒的表面粗糙度和亲水性，但显著提高了其电子转移能力，并增强了 GOx 的催化特性。因此，这些影响因素的综合作用导致了葡萄糖传感器性能的显著提高，即灵敏度增加，检测限降低。确定最佳掺杂 Ag 量为 2 mM，相应的葡萄糖传感器表现出 3.85 μA/（mM·cm²）的灵敏度、1.5 μM 的检测限、1.5×10-6.5 mM 的线性范围和 3.87 mM 的米氏常数。此外，该葡萄糖传感器对尿素、抗坏血酸和尿酸具有优异的选择性，并且还表现出良好的存储稳定性。这些结果表明 ZnO-Ag 纳米棒是构建其他酶生物传感器的有前途的基质材料。
