Acta Chimica Sinica ›› 2012, Vol. 70 ›› Issue (21): 2213-2219.DOI: 10.6023/A12060284 Previous Articles     Next Articles



张谦a,b, 吴抒遥a,b, 何茂伟a,b, 张玲c, 刘洋d, 李景虹d, 宋溪明a,b   

  1. a 辽宁大学绿色合成与先进材料制备化学辽宁省重点实验室 沈阳 110036;
    b 辽宁大学化学院 沈阳 110036;
    c 沈阳师范大学化学与生命科学学院 沈阳 110034;
    d 清华大学化学系 北京 100084
  • 投稿日期:2012-06-06 发布日期:2012-09-17
  • 通讯作者: 李景虹, 宋溪明,
  • 基金资助:
    项目受国家自然科学基金(Nos. 21071070, 21005046, 20901035, 51273087, 21235004, 21203126)、辽宁省高等学校创新团队基金(No. LT2011001)、辽宁省自然科学基金(No. 201202088)、2013年辽宁大学青年科研基金和辽宁大学创新人才培养基金资助.

Preparation and Bioelectrochemical Application of Gold Nanoparticles-Chitosan-Graphene Nanomaterials

Zhang Qiana,b, Wu Shuyaoa,b, He Maoweia,b, Zhang Lingc, Liu Yangd, Li Jinghongd, Song Xi-Minga,b   

  1. a Liaoning Provincial Key Laboratory for Green Synthesis and Preparative Chemistry of Advanced Materials, Liaoning University, Shenyang 110036;
    b College of Chemistry, Liaoning University, Shenyang 110036;
    c College of Chemistry and Life Science, Shenyang Normal University, Shenyang 110034;
    d Department of Chemistry, Tsinghua University, Beijing 100084
  • Received:2012-06-06 Published:2012-09-17
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Nos. 21071070, 21005046, 20901035, 51273087, 21235004 and 21203126), the Program for Liaoning Innovative Research Team in University (No. LT2011001), Natural Science Foundation of Liaoning Province (No. 201202088), the Foundation for Young Scholars of Liaoning University (2013) and the Foundation of 211 Project for Innovative Talents Training, Liaoning University.

Based on the covalent modification and in-situ reduction, chitosan and gold nanoparticles were integrated with graphene to form a novel gold nanoparticles/chitosan-graphene (AuNPs/Chit-GP) nanocomposite. The process of the fabrication of AuNPs/Chit-GP nanocomposite consisted of the following steps. Firstly, carboxyl-GP was prepared based on the reduction and modification of graphene oxide (GO). Thereafter, chitosan was covalently functionalized onto graphene nanosheet to fabricate Chit-GP. The AuNPs/Chit-GP nanocomposite was finally synthesized by the in-situ reduction of HAuCl4 in the presence of Chit-GP. Fourier transform infrared (FT-IR) spectra, ultraviolet-visible (UV-vis) absorption spectra, transmission electron microscopy (TEM) and X-ray diffraction (XRD) were utilized to characterize structure and morphology of the as synthesized nanocomposite. Because of the surface functionalization of chitosan, the composite exhibited positive charge. In that case, the negatively charged glucose oxidase (GOD) could further immobilize onto AuNPs/Chit-GP via electrostatic interaction under mild experimental condition. With the advantages of graphene, Au nanoparticles and chitosan, AuNPs/Chit-GP can offer a conductive and favorable microenvironment for the immobilized GOD to achieve direct electrochemistry. The direct electron transfer (DET) reaction of the immoblized GOD was studied by cyclic voltammetry in 0.1 mol/L phosphate buffer solution (PBS, pH 7.4). A pair of well-defined, quasi-reversible redox peaks of GOD were obtained at GOD/AuNPs/Chit-GP/GC modified electrode, with a formal potential (vs. Ag/AgCl) being -0.44 V. Moreover, the as fabricated GOD/AuNPs/Chit-GP/GC modified electrode exhibited excellent catalytic performance towards glucose. The electrocatalytic response of GOD/AuNPs/Chit-GP/GC modified electrode altered linearly with the glucose concentration ranging from 2.1 to 5.7 μmol/L. The detection limit and the sensitivity of the enzyme electrode were 0.7 μmol/L (S/N=3) and 79.71 mA·cm-2·mM-1, respectively. Because of the biocompability of the AuNPs/Chit-GP, GOD/AuNPs/Chit-GP/GC modified electrode also exhibited acceptable reproducibility and excellent stability. Therefore, such a novel nanocomposite composed of metal nanoparticles, biocompatible macromolecules and graphene provides an efficient platform for the development of mediator-free electrochemical biosensors.

Key words: gold nanoparticles, chitosan, graphene, glucose oxidase, direct electrochemistry