Amperometric choline biosensors prepared by layer-by-layer deposition of choline oxidase on the Prussian blue-modified platinum electrode |
| |
Authors: | Shi Haibin Yang Yu Huang Jiadong Zhao Zixia Xu Xinhua Anzai Jun-Ichi Osa Tetsuo Chen Qiang |
| |
Institution: | a College of Life Science, Nankai University, Tianjin 300071, China b School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China c Graduate School of Pharmaceutical Sciences, Tohoku University, Aramaki, Aoba-ku, Sendai 980-8578, Japan |
| |
Abstract: | An amperometric choline biosensor was developed by immobilizing choline oxidase (ChOx) in a layer-by-layer (LBL) multilayer film on a platinum (Pt) electrode modified with Prussian blue (PB). 6-O-Ethoxytrimethylammoniochitosan chloride (EACC) was used to prepare the ChOx LBL films. The choline biosensor was used at 0.0 V versus Ag/AgCl to detect choline and exhibited good characteristics such as relative low detection limit (5 × 10−7 M), short response time (within 10 s), high sensitivity (88.6 μA mM−1 cm−2) and a good selectivity. The results were explained based on the ultrathin nature of the LBL films and the low operating potential that could be due to the efficient catalytic reduction of H2O2 by PB. In addition, the effects of pH, temperature and applied potential on the amperometric response of choline biosensor were evaluated. The apparent Michaelis-Menten constant was found to be (0.083 ± 0.001) ×10−3 M. The biosensor showed excellent long-term storage stability, which originates from a strong adsorption of ChOx in the EACC multilayer film. When the present choline biosensor was applied to the analysis of phosphatidylcholine in serum samples, the measurement values agreed satisfactorily with those by a hospital method. |
| |
Keywords: | Choline oxidase Amperometric biosensor Layer-by-layer Prussian blue 6-O-Ethoxytrimethylammoniochitosan chloride |
本文献已被 ScienceDirect PubMed 等数据库收录! |
|