基于纳米金和硫堇固定酶的过氧化氢生物传感器答辩人：陈.ppt

基于纳米金和硫堇固定酶的过氧化氢生物传感器答辩人：陈.ppt基于纳米金和硫堇固定酶的过氧化氢生物传感器答辩人:陈贤光( 03 应化) 指导老师:童叶翔教授邹小勇教授 广州 Hydrogen Peroxide Biosensor Based on Immobilizing Enzyme by Gold Nanoparticles and Thionine ① CHEN, Xian-Guang ZOU, Xiao-Yong TONG, Ye-Xiang * School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, China ① This paper will submit to Acta Chim. Sinica . 1. Introduction Mechanism of Hydrogen Peroxide Biosensor Guilbault G. G. , et. al . Anal. Chim. Acta. , 1973, 64: 439-445. H 2O 2 H 2O HRP Ox HRP R e - Electrode2H 2O 2 2H 2O+O 2 HRP HRP=HorseradishPeroxidase 1. Introduction Fabrication of hydrogen peroxide biosensor made in our work 1. Introduction Catalytic reaction of H 2O 2 appear in the system HRP Ox HRP R e -Electrode H 2O 2 H 2O BQHQ Thio RThio Ox HQ=Hydroquinone,BQ=Benzoquinone,Thio=Thionine 2. Results and Discussion Prepare GNs by sol-gel method CH 2C H 2CCOONa HOCOONa COONa+4HAuCl 4+5H 2O COONaCOOH 3 +4Au+16HCl Fig. 1 TEM image of GNs. ( d = 20 nm ) 2. Results and Discussion Electrochemical impedance spectrum (EIS) Fig. 2 Nyquist plot of EIS of the electrodes (a) and equivalent circuit (b) of the biosensor. R solR ct C dlW (a) (b) R app : electrode apparent resistance; R sol : solution resistance; R ct : charge transfer resistance. 1724 9326 1179 a 6334 9623 2208 b 7580 5016 d 3780 9882 3536 c R ct / Ω R sol / Ω R app / Ω Electrode Table 1 Electrochemistry parameters 2. Results and Discussion Atomic force microscopy (AFM) images Fig. 3 Three-dimensional AFM images of bare Pt (a), Pt/GNs (b), Pt/GNs/Thio (c) and Pt/GNs/Thio/(HRP-GNs) (d) electrode. 2. Results and Discussion Cyclic voltammgrams (CVs) (b) Fig. 5 CVs of electrocatalysis of the biosensor to H 2O 2 in pH PBS containing 1 × 10 -3 mol/L hydroquinone. (a) Fig. 4 CVs (a) of the biosensor at different scan rates in blank pH PBS and the linear calibration curve between scan rates and cat