A novel glucose biosensor based on immobilization of glucose oxidase in chitosan on a glassy carbon electrode modified with gold-platinum alloy nanoparticles/multiwall carbon nanotubes.
A novel glucose biosensor was constructed, based on the immobilization of glucose oxidase (GOx) with cross-linking in the matrix of biopolymer chitosan (CS) on a glassy carbon electrode (GCE), which was modified with gold-platinum alloy nanoparticles (Au-PtNPs) by electrodeposition on multiwall carbon nanotubes (CNTs) in CS film (CNTs/CS). The properties of Au-PtNPs/CNTs/CS were characterized by scan electron microscopy (SEM), X-ray diffraction (XRD), cyclic voltammetry (CV), and electrochemical impedance spectra (EIS). Primary study indicated that Au-PtNPs/CNTs had a better synergistic electrocatalytic effect on the reduction of hydrogen peroxide than did AuNPs/CNTs or PtNPs/CNTs at a low applied potential window. With GOx as a model enzyme, a new glucose biosensor was fabricated. The biosensor exhibited excellent performances for glucose at a low applied potential (0.1V) with a high sensitivity (8.53 microA mM(-1)), a low detection limit (0.2 microM), a wide linear range (0.001-7.0 mM), a fast response time (<5s), and good reproducibility, stability, and selectivity. In addition, the biosensor was applied in the determination of glucose in human blood and urine samples, and satisfied results were obtained.
Kang
Xinhuang
X
School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, People's Republic of China.
Mai
Zhibin
Z
Zou
Xiaoyong
X
Cai
Peixiang
P
Mo
Jinyuan
J
D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D048271:Chitosan / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism; D005947:Glucose / Q000032:analysis* / Q000737:chemistry; D005949:Glucose Oxidase / Q000737:chemistry* / Q000378:metabolism; D006047:Gold Alloys / Q000737:chemistry; D006861:Hydrogen Peroxide / Q000737:chemistry / Q000378:metabolism; D053768:Metal Nanoparticles / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry; D012680:Sensitivity and Specificity
D004800:Enzymes, Immobilized; D006047:Gold Alloys; D037742:Nanotubes, Carbon; D010984:Platinum; D048271:Chitosan; D006861:Hydrogen Peroxide; D005949:Glucose Oxidase; D005947:Glucose