化学学报 ›› 2012, Vol. 70 ›› Issue (11): 1315-1321.DOI: 10.6023/A1111012 上一篇    下一篇

研究论文

新型石墨烯/金/功能导电高分子/过氧化氢生物传感器的制备及应用

夏前芳, 黄颖娟, 杨雪, 李在均   

  1. 江南大学化学与材料工程学院 无锡 214122
  • 投稿日期:2011-11-01 修回日期:2012-04-12 发布日期:2012-04-12
  • 通讯作者: 李在均 E-mail:zaijunli@263.net
  • 基金资助:

    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)、江苏省“青蓝工程”和浙江赞宇基金资助项目.

Preparation and its Application of Novel Graphene/Gold/Functional Conducting Polymer/Hydrogen Peroxide Biosensor

Xia Qianfang, Huang Yingjuan, Yang Xue, Li Zaijun   

  1. School of Chemical and Materials Engineering, Jiangnan University, Wuxi 214122
  • Received:2011-11-01 Revised:2012-04-12 Published:2012-04-12
  • 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) and Zanyu Science Foundation of Zhejiang ZanYu Technology Limited Company.

石墨烯材料和酶的固定对石墨烯基生物传感器性能及应用至关重要。金电极依次放入氧化石墨(0.05 mg/mL)和氯金酸(0.05 mM)溶液中进行控制电位电解,循环以上操作20 次后,转移至2,5-二(2-噻吩)-1-对苯甲酸吡咯单体溶液采用循环伏安法进行电聚合形成含有羧基的导电高分子膜,然后以DHC/NHS 为活化剂将辣根过氧化物酶共价键合在修饰电极表面制备过氧化氢生物传感器。研究表明,交替电沉积得到的石墨烯/金纳米复合材料分散性好,所制备的生物传感器对过氧化氢的氧化还原过程有显著的催化作用。过氧化氢浓度在2~200 nM 之间传感器的电流响应与浓度呈线性关系,相关系数(R2)为0.9996,方法的检测限是0.67 nM (S/N=3),灵敏度明显优于现有文献报道。此外,共价键合方式固定酶使传感器的稳定性和方法的重现性大大提高。5 nM 的过氧化氢溶液测定20 次,相对标准偏差为1.2 %。在4℃下储藏3 个月传感器电化学响应变化值少于3 %。该方法已成功应用于牛奶样品中痕量过氧化氢的测定.

关键词: 石墨烯, 纳米金, 功能导电高分子, 生物传感器, 过氧化氢

Immobilizations of the graphene-based materials and enzyme are very important to electrochemical properties and use of the biosensor. In this work, a 0.005 mg/mL of graphite oxide and 0.005 mM of chlorauric acid were in sequence electrodeposited on the surface of gold electrode with potentiostatic elec-trolysis. After above procedure was repeated for 20 cycles, 2,5-di-(2-thienyl)-1-pyrrole-1-(p-benzoic acid) was electropolymerized on the modified electrode by cyclic voltammetry and finally formed functional conducting polymer film containing carbonyl groups on surface of the graphene/gold nanocomposite. To prepare hydrogen peroxide biosensor, the horseradish peroxidase was subsequently connected covalently to the film with DHC/NHS as activator. Research results indicated that the graphene/gold nanocomposite obtained using alternating electro-deposition has excellent dispersivity. The biosensor based on the material offers remarkable catalysis performance to the redox of hydrogen peroxide on the electrode surface. Current response of the sensor increases linearly with the increasing concentration of hydrogen peroxide over the range from 2 nM to 200 nM, with a correlation coefficient (R2) of 0.9996. The detection limit was found to be 0.67 nM (S/N=3). The sensitivity is more than other sensor reported in the literatures. In addition, covalent immobilization of the enzyme results in increasing the stability and reproducibility of the sensor. The relative standard deviation is 1.2 % for determination of 5 nM hydrogen peroxide for 20 times. After the sensor was stored at 4℃ for three months, its change value of the response is lower than 3%. The proposed method has been successfully applied to detect trace hydrogen peroxide in milk sample.

Key words: graphene, gold nanoparticles, functional conducting polymer, biosensor, hydrogen peroxide