文献类型：期刊文献

英文题名：Clay-chitosan-gold nanoparticle nanohybrid: Preparation and application for assembly and direct electrochemistry of myoglobin

作者：Zhao, Xiaojuan[1];Mai, Zhibin[1];Kang, Xinhuang[2];Dai, Zong[1];Zou, Xiaoyong[1]

机构：[1]Sun Yat Sen Univ, Sch Chem & Chem Engn, Guangzhou 510275, Peoples R China;[2]Guangdong Ocean Univ, Coll Sci, Zhanjiang 524088, Peoples R China

年份：2008

卷号：53

期号：14

起止页码：4732

外文期刊名：ELECTROCHIMICA ACTA

收录：SCI-EXPANDED(收录号：WOS:000255604900019)、、EI(收录号：20081311176215)、Scopus(收录号：2-s2.0-41049087197)、WOS

语种：英文

外文关键词：nanohybrid; myoglobin; direct electrochemistry; clay; chitosan-stabilized gold nanoparticles

外文摘要：A biocompatible nanohybrid material (clay/AuCS) based on clay, chitosan and gold nanoparticles was explored. The material could provide a favorable microenvironment for proteins to realize the direct electron transfer on glassy carbon electrodes (GCE). Myoglobin (Mb), as a model protein to investigate the nanohybrid, was immobilized between the clay/AuCS film and another clay layer. Mb in the system exhibited a pair of well-defined and quasi-reversible redox peaks at -0.160 V (vs. saturated Ag/AgCl electrode) in 0.1 M PBS (pH 7.0), corresponding to its heme Fe-III/Fe-II redox couples. UV-vis spectrum suggested that Mb retained its native conformation in the system. Basal plane spacing of clay obtained by X-ray diffraction (XRD) indicated that there was an intercalation-exfoliation-restacking process among Mb, AuCS and clay during the modified film drying. Excellent biocatalytic activity of Mb in the modified system was exemplified by the reduction of hydrogen peroxide and nitrite. The linear range of H2O2 determination was from 3.9 x 10(-5) to 3.0 x 10(-3) M with a detection limit of 7.5 mu M based on the signal to noise ratio of 3. The kinetic parameters such as alpha (charge transfer coefficient), k(s) (electron transfer rate constant) and K-m (Michaelis-Menten constant) were evaluated to be 0.55, 2.66 +/- 0.15 s(-1) and 5.10 mM, respectively. (C) 2008 Elsevier Ltd. All rights reserved.