化学学报 ›› 2012, Vol. 70 ›› Issue (19): 2079-2084.DOI: 10.6023/A12060294 上一篇    下一篇

研究论文

石墨烯基葡萄糖生物传感器的电化学制备及应用

夏前芳, 罗丹, 李在均   

  1. 江南大学 化学与材料工程学院 无锡 214122
  • 收稿日期:2012-06-08 出版日期:2012-10-14 发布日期:2012-08-06
  • 通讯作者: 李在均 E-mail:zaijunli@263.net
  • 基金资助:

    项目受国家自然科学基金(No. 21176101);国家科技支撑计划(No. 2011BAK10B03);浙江省自然科学基金(No. Y4100729)和江苏省“青蓝工程”资助.

Electrochemical Fabrication and Application of the Glucose Biosensor Based on Graphene

Xia Qianfang, Luo Dan, Li Zaijun   

  1. School of Chemical and Materials Engineering, Jiangnan University, Wuxi 214122
  • Received:2012-06-08 Online:2012-10-14 Published:2012-08-06
  • Supported by:

    Project supported by the National Natural Science Foundation of China (No. 21176101), the National Science and Technology Support Plan (No. 2011BAK10B03), Qing Lan Project, the Natural Science Foundation of Zhejiang Province (No. Y4100729).

修饰材料和酶在电极表面上的固定是目前制约葡萄糖生物传感器广泛应用的主要因素. 交替电沉积石墨烯和纳米金在玻碳电极表面以构建石墨烯/金复合材料. 电极放入2,5-二(2-噻吩)-1-对苯甲酸吡咯溶液(DPB)进行电聚合形成含有大量游离羧基的导电高分子膜. 以1-乙基-3-(3-二甲基氨丙基)-碳化二亚胺和N-羟基琥珀酰亚胺的混合溶液为活化剂将葡萄糖氧化酶共价键合于电极表面制备生物传感器. 采用拉曼光谱、X-射线衍射和扫描电镜对石墨烯/金复合材料的形貌和结构分析揭示交替电沉积得到了分散性良好的石墨烯/金复合材料. 此外, 修饰电极的电化学性质也被详细研究. 它的电活性面积、载酶量和表观米氏常数分别为0.1403 cm2、7.73×10-11 mol·cm-2和5.23×10-5 mol·L-1. 当葡萄糖浓度在5×10-6~5×10-4 mol·L-1之间, 传感器的差分脉冲伏安峰电流变化符合线性关系. 方法的检出限为1.7×10-6 mol·L-1. 传感器在4 ℃下放置四周后其电化学响应仍能保持95%以上. 由于石墨烯/金复合材料的电催化作用和导电高分子对酶的共价固定, 方法在灵敏度、选择性、稳定性和重现性方面优于文献报道的萄葡糖生物传感器, 它成功用于血清中微量葡萄糖的测定.

关键词: 石墨烯/金复合材料, 功能导电高分子, 生物传感器, 葡萄糖

Immobilizations of the modified materials and enzyme on the electrode sufrace are main factors that restrict wide use of the glucose biosensor now. Graphene and gold nanoparticles were alternately electrodeposited on the surface of glassy carbon electrode to fabricate the graphene/gold composites. The electrode was then immersed in a 2,5-di-(2-thienyl)-1- pyrrole-1-(p-benzoic acid) solution (DPB) to electrochemically polymerize and form the poly(DPB) conducting polymer film which contains a large number of free carbonyl groups. In order to fabricate the glucose biosensor, the glucose oxidase was covalently connected to the poly(DPB) conducting polymer film with the mixture solution of 1-ethyl-3-(3-dimethyl- aminepropyl)carbodiimide and N-hydroxysuccinimide as an activator. In this study, Raman spectrum, X-ray diffraction pattern and scanning electron microscope were used to characterize morphology and structure of the as-prepared graphene/gold composites, respectively. The results have demonstrated that a well-dispersible graphene/gold composites was obtained using such a alternate electrodeposition. Moreover, electrochemical properties of the biosensor were also investigated in detail. It was found that the electrochemical activity area, amounts of the immobilized enzyme and the apparent Michaelis constant of the modified electrode were 0.1403 cm2, 7.73×10-11 mol·cm-2 and 5.23×10-5 mol·L-1, respectively. When the concentration of glucose ranged from 5×10-6 mol·L-1 to 5×10-4 mol·L-1, the peak current change of differential pulse voltammetric response of the biosensor will increase linearly. The detection limit was found to be 1.7×10-6 mol·L-1. After the biosensor was placed in 4 ℃ for 4 weeks, the electrochemical response can remain more than 95%. Due to electrocatalysis of the graphene/gold composite and covalent immobilization of the enzyme with the conducting polymer, the proposed method provides a better sensitivity, selectivity, stability and reproducibility than that of other glucose biosensors reported in literatures. It has been successfully applied to determination of glucose in various serum samples.

Key words: graphene/gold composites, functional conducting polymer, biosensor, glucose