ZnO nanorods, with the c-axis orientation used for transparent conductors, solar cells, sensors especially the functionalized ZnO nanorods with some kinds of enzymes have been used for biosensor. In this work, we desc...ZnO nanorods, with the c-axis orientation used for transparent conductors, solar cells, sensors especially the functionalized ZnO nanorods with some kinds of enzymes have been used for biosensor. In this work, we describe the process immobilization of galactose oxidase on ZnO nanorods surface with glutaraldehyde as a cross-linker molecule to make the working electrode in electrochemical biosensor. ZnO nanorods were grown on FTO （Fluorine-doped tin oxide） substrate by solution method at low temperature. The crystalline phase and orientation of ZnO nanorods were identified using X-ray diffraction. The efficiency of the immobilization was calculated by Braford method showed that about 36% enzyme content was immobilized on ZnO nanorods surface. The working electrode based on the immobilized ZnO nanorods was tested in galactose solution by CV （cyclic voltammetry） method indicated the value of current intensity is about 0.14 μA. These results clearly demonstrate the potential of galactose sensor based on ZnO nanorod.展开更多
Based on the layer-by-layer self-assembly of positively charged cetyltrimethylammonium bromide （CTAB） wrapped gold na- norods （AuNRs） and negatively charged superoxide dismutase （SOD） from their aqueous solution...Based on the layer-by-layer self-assembly of positively charged cetyltrimethylammonium bromide （CTAB） wrapped gold na- norods （AuNRs） and negatively charged superoxide dismutase （SOD） from their aqueous solutions on cysteine modified gold electrode （Cys/Au）, a third generation electrochemical biosensor （（SOD/AuNRs）2/Cys/Au） for superoxide anion （02＂-） was developed. The two layers assembly of SOD/AuNRs can significantly enhance the direct electron transfer between SOD and the electrode. The functional enzymatic activities of the SOD offer an electrochemical approach to the determination of 02＂-. In the reductive regions, the proposed sensor exhibits excellent analytical performances, such as wide linear range （200 nM to 0.2 mM O2-）, low detection limit （100 nM O2-）, high sensitivity （22.11 nA cm-2 μM-1）, short response time （less than 5 s）, good stability and reproducibility, while no obvious interferences are caused by commonly met interfering species including hydrogen peroxide （H202）, uric acid （UA） and ascorbic acid （AA）.展开更多
文摘ZnO nanorods, with the c-axis orientation used for transparent conductors, solar cells, sensors especially the functionalized ZnO nanorods with some kinds of enzymes have been used for biosensor. In this work, we describe the process immobilization of galactose oxidase on ZnO nanorods surface with glutaraldehyde as a cross-linker molecule to make the working electrode in electrochemical biosensor. ZnO nanorods were grown on FTO （Fluorine-doped tin oxide） substrate by solution method at low temperature. The crystalline phase and orientation of ZnO nanorods were identified using X-ray diffraction. The efficiency of the immobilization was calculated by Braford method showed that about 36% enzyme content was immobilized on ZnO nanorods surface. The working electrode based on the immobilized ZnO nanorods was tested in galactose solution by CV （cyclic voltammetry） method indicated the value of current intensity is about 0.14 μA. These results clearly demonstrate the potential of galactose sensor based on ZnO nanorod.
基金supported by the National Natural Science Foundation of China (20805013, 20905024&21075031)the National Basic Research Program of China (2009CB421601 & 2011CB911002)the Natural Science Foundation of Hunan Province (09JJ4006 & 09JJ4007)
文摘Based on the layer-by-layer self-assembly of positively charged cetyltrimethylammonium bromide （CTAB） wrapped gold na- norods （AuNRs） and negatively charged superoxide dismutase （SOD） from their aqueous solutions on cysteine modified gold electrode （Cys/Au）, a third generation electrochemical biosensor （（SOD/AuNRs）2/Cys/Au） for superoxide anion （02＂-） was developed. The two layers assembly of SOD/AuNRs can significantly enhance the direct electron transfer between SOD and the electrode. The functional enzymatic activities of the SOD offer an electrochemical approach to the determination of 02＂-. In the reductive regions, the proposed sensor exhibits excellent analytical performances, such as wide linear range （200 nM to 0.2 mM O2-）, low detection limit （100 nM O2-）, high sensitivity （22.11 nA cm-2 μM-1）, short response time （less than 5 s）, good stability and reproducibility, while no obvious interferences are caused by commonly met interfering species including hydrogen peroxide （H202）, uric acid （UA） and ascorbic acid （AA）.
