Electrochemical biosensor based on multi-walled carbon nanotubes and Au nanoparticles synthesized in chitosan.
A new biosensor is prepared by cross-linking glucose oxidase (GOD) with glutaradehyde at the electrode combining Au nanoparticles (AuNP) with multi-walled carbon nanotubes (MWCNTs). Au nanoparticles-doped chitosan (CS) solution (AuNP-CS) is prepared by treating the CS solution followed by chemical reduction of Au (III) with NaBH4. MWCNTs are then dispersed in AuNP-CS solution. TEM, FT-IR, and UV-Vis show that the AuNP-CS solution is highly dispersed and stable. The synergistic effect between AuNP and CNTs of the AuNP-CNTs-CS material has been investigated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and amperometric methods. The modified glassy carbon electrode (GCE) allows low-potential detection of H2O2 with high sensitivity and fast response time. With the immobilization of GOD, a biosensor has been constructed. In phosphate buffer solutions (PBS, pH 7.0), nearly free interference determination of glucose has been realized at 0.4 V(vs. Ag/AgCl/3.0 M KCI) with a wide linear range from 2.0 x 10(-5) to 1.5 x 10(-2) M and a fast response time within 5s. The biosensor has been used to determine glucose in human serum samples and the results are satisfactory.
Kang
Xinhuang
X
School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China.
Mai
Zhibin
Z
Zou
Xiaoyong
X
Cai
Peixiang
P
Mo
Jinyuan
J
D015374:Biosensing Techniques; D002384:Catalysis; D048271:Chitosan / Q000737:chemistry*; D004563:Electrochemistry / Q000379:methods*; D004566:Electrodes; D005947:Glucose / Q000737:chemistry; D005949:Glucose Oxidase / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D036103:Nanotechnology / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry*; D012680:Sensitivity and Specificity
D037742:Nanotubes, Carbon; D006046:Gold; D048271:Chitosan; D005949:Glucose Oxidase; D005947:Glucose