Direct electrochemistry of lactate dehydrogenase immobilized on silica sol-gel modified gold electrode and its application
| Autor: | Huie Zheng, Jingyue Zhuang, Quan Xu, Keyu Wang, Yongbo Sun, Shuping Bi, Jiongjia Cheng, Junwei Di, Xiangyin Mo |
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| Rok vydání: | 2007 |
| Předmět: |
Detection limit
L-Lactate Dehydrogenase Inorganic chemistry Biomedical Engineering Biophysics Enzyme electrode Silica Gel Electrons General Medicine Resorcinol Electrochemistry Enzymes Immobilized Silicon Dioxide Immunoenzyme Techniques chemistry.chemical_compound Electron transfer chemistry Electrode Gold Biosensor Voltammetry Electrodes Gels Biotechnology |
| Zdroj: | Biosensorsbioelectronics. 23(5) |
| ISSN: | 0956-5663 |
| Popis: | The direct electrochemistry of lactate dehydrogenase (LDH) immobilized in silica sol–gel film on gold electrode was investigated, and an obvious cathodic peak at about −200 mV (versus SCE) was found for the first time. The LDH-modified electrode showed a surface controlled irreversible electrode process involving a one electron transfer reaction with the charge-transfer coefficient ( α ) of 0.79 and the apparent heterogeneous electron transfer rate constant ( K s ) of 3.2 s −1 . The activated voltammetric response and decreased charge-transfer resistance of Ru(NH 3 ) 6 2+/3+ on the LDH-modified electrode provided further evidence. The surface morphologies of silica sol–gel and the LDH embedded in silica sol–gel film were characterized by SEM. A potential application of the LDH-modified electrode as a biosensor for determination of lactic acid was also investigated. The calibration range of lactic acid was from 2.0 × 10 −6 to 3.0 × 10 −5 mol L −1 and the detection limit was 8.0 × 10 −7 mol L −1 at a signal-to-noise ratio of 3. Finally, the effect of environmental pollutant resorcinol on the direct electrochemical behavior of LDH was studied. The experimental results of voltammetry indicated that the conformation of LDH molecule was altered by the interaction between LDH and resorcinol. The modified electrode can be applied as a biomarker to study the pollution effect in the environment. |
| Databáze: | OpenAIRE |
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