化学学报 ›› 2014, Vol. 72 ›› Issue (6): 713-719.DOI: 10.6023/A14020138 上一篇    下一篇

研究论文

石墨烯量子点功能化金纳米粒子的制备及作为过氧化物模拟酶用于葡萄糖检测

郭颖, 李午戊, 郑敏燕, 黄怡   

  1. 咸阳师范学院化学与化工学院 咸阳 712000
  • 投稿日期:2014-02-26 发布日期:2014-04-25
  • 通讯作者: 郭颖 E-mail:guoying207@126.com
  • 基金资助:
    项目受国家自然科学基金(No.21275096)和陕西省教育厅科学研究计划(No.2010JK898)资助.

Facile Preparation of Graphene Dots Functionalized Au Nanoparticles and Their Application as Peroxidase Mimetics in Glucose Detection

Guo Ying, Li Wuwu, Zheng Minyan, Huang Yi   

  1. College of Chemistry & Chemical Engineering, Xianyang Normal University, Xianyang 712000
  • Received:2014-02-26 Published:2014-04-25
  • Supported by:
    Project supported by the National Natural Science Foundation of China (No.21275096) and the Scientific Research Plan Projects of Education Department of Shaanxi Province (No.2010JK898).

基于石墨烯量子点(GQD)的还原性,在无需外加保护剂的条件下,采用一步法成功制备了稳定性高、分散性好的石墨烯量子点功能化的金纳米粒子(GQD@AuNPs).所制备的GQD@AuNPs有优良的过氧化物模拟酶催化活性,能够有效地催化H2O2氧化3,3’,5,5’-四甲基联苯胺(TMB)产生显色反应.以TMB为模型底物,研究了催化条件(温度和pH)对催化活性的影响.电子自旋共振光谱(ESR)结果表明,GQD@AuNPs与辣根过氧化物酶(HRP)类似,能有效地催化H2O2分解成羟基自由基(·OH).基于此,结合葡萄糖在葡萄糖氧化酶(GOx)作用下产生H2O2的原理,建立了可视化检测血清中葡萄糖含量的简便方法.在优化条件下,本方法的检测范围为2.0×l0-6~4.0×l0-5 mol·L-1,检出限为3.0×l0-7 mol·L-1,并对实际样品进行测定,测定结果与临床结果一致.

关键词: 石墨烯量子点, 纳米金, 过氧化物模拟酶, 葡萄糖

Based on the reducing property of graphene dots, we developed a facile strategy to synthesize well-stable graphene dots functionalized Au nanoparticles (denoted as GQD@AuNP) by one-step process at low temperature without added protecting agent.The prepared GQD@AuNP were characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV-vis absorption spectra.It was found that the as-prepared GQD@AuNP are spherical and monodisperse with an average diameter of ca.10 nm.Graphene dots not only act as a mild reductant to reduce HAuCl4, but also as a capping agent to endow the GQD@AuNP with good stability in aqueous solvent and monodispersity and restrains the Au crystal growth, making the particles have narrow size distribution.Furthermore, the as-prepared GQD@AuNP showed an excellent intrinsic peroxidese-like activity, which could catalyze oxidization of 3,3',5,5'-tetramethylbiphenyl (TMB) by H2O2 to produce a colour variation.Using TMB as substrate, we systematically studied the effect of a series of conditions, such as temperature and pH, on the catalytic activity of the as-prepared GQD@AuNP.Results of electron paramagnetic resonance (ESR) suggest that the catalyse-mimic activity of the GQD@AuNP like HRP and effectively catalyzed the decomposition of H2O2 into ·OH radicals.On this basis, a highly sensitive and rapid colorimetric and visualization method was developed for glucose in blood samples, when combined with glucose oxidase (GOx).Under optimum conditions, the proposed method allowed the detection of glucose in the range of 2.0×l0-6 to 4.0×l0-5 mol·L-1 with detectable glucose as low as 3.0×l0-7 mol·L-1.Furthermore, another three sugars existing in the human serum, including maltose, fructose and lactose were detected by this method, which indicated the little disturbance by maltose and fructose, while no remarkable signals were observed for the lactose.This proposed method has been successfully applied to detect glucose in serum samples with good accuracy and precision.

Key words: graphene dots, Au nanoparticles, peroxidase mimetics, glucose