Zhu Hong, Lu Xiaoqing, Li Meixian, Shao Yuanhua, Zhu Zhiwei
Institute of Analytical Chemistry, College of Chemistry and Molecular Engineering, Peking University, Beijing, PR China.
Talanta. 2009 Oct 15;79(5):1446-53. doi: 10.1016/j.talanta.2009.06.010. Epub 2009 Jun 12.
In this paper, a novel nonenzymatic glucose voltammetric sensor based on a kind of nanocomposite of gold nanoparticles (GNPs) embedded in multi-walled carbon nanotubes (MWCNTs)/ionic liquid (IL) gel was reported. The surface morphology of this nanocomposite was characterized using X-ray photoelectron spectrometer (XPS), scanning electron microscope (SEM) and transmission electron microscope (TEM), respectively. It can be found that most of GNPs lie close to the ektexine of MWCNTs and the others have obviously inserted the inner of MWCNTs through the defects or ends of MWCNTs, due to the attraction between GNPs and MWCNTs as well as the repulsion between GNPs and IL. Voltammetry was used to evaluate the electrocatalytic activities of the nanocomposite biosensor toward nonenzymatic glucose oxidation in alkaline media. The GNPs embedded in MWCNTs/IL gel have strong and sensitive voltammetric responses to glucose, owing to a possible synergistic effect among GNPs, MWCNTs and IL. Under the optimal condition, the linear range for the detection of the glucose is 5.0-120 microM with the correlation coefficient of 0.998, based on the oxidation peak observed during cathodic direction of the potential sweep. The kinetics and mechanism of glucose electro-oxidation were intensively investigated in this system. This kind of nanocomposite biosensor is also highly resistant toward poisoning by chloride ions and capable of sensing glucose oxidation in the presence of 20 microM uric acid and 70 microM ascorbic acid. This work provides a simple and easy approach to the detection of glucose in body fluid with high sensitivity and excellent selectivity.
本文报道了一种基于嵌入多壁碳纳米管（MWCNTs）/离子液体（IL）凝胶中的金纳米颗粒（GNPs）纳米复合材料的新型非酶葡萄糖伏安传感器。分别使用X射线光电子能谱仪（XPS）、扫描电子显微镜（SEM）和透射电子显微镜（TEM）对该纳米复合材料的表面形貌进行了表征。可以发现，由于GNPs与MWCNTs之间的吸引力以及GNPs与IL之间的排斥力，大多数GNPs靠近MWCNTs的外表面，而其他GNPs则通过MWCNTs的缺陷或末端明显插入到MWCNTs内部。采用伏安法评估了该纳米复合生物传感器在碱性介质中对非酶葡萄糖氧化的电催化活性。嵌入MWCNTs/IL凝胶中的GNPs对葡萄糖具有强烈而灵敏的伏安响应，这可能是由于GNPs、MWCNTs和IL之间存在协同效应。在最佳条件下，基于在电位扫描阴极方向观察到的氧化峰，葡萄糖检测的线性范围为5.0 - 120 μM，相关系数为0.998。对该体系中葡萄糖电氧化的动力学和机理进行了深入研究。这种纳米复合生物传感器对氯离子中毒也具有高度抗性，并且能够在存在20 μM尿酸和70 μM抗坏血酸的情况下检测葡萄糖氧化。这项工作为高灵敏度和高选择性地检测体液中的葡萄糖提供了一种简单易行的方法。
