| 18371787 |
Du D, Ding J, Cai J, Zhang J, Liu L: In situ electrodeposited nanoparticles for facilitating electron transfer across self-assembled monolayers in biosensor design. Talanta. 2008 Feb 15;74(5):1337-43. Epub 2007 Sep 14.
Gold nanoparticles (AuNPs) were synthesized in situ and electrodeposited onto Au substrate. The AuNPs modified interface facilitates electron transfer across self-assembled monolayers (SAMs) of 11-mercaptoundecanoic acid (MUA). After activation of surface carboxyl groups with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide, the interface displayed good stability for immobilization of biomolecules. These modification processes were characterized by contact angle measurement, cyclic voltammetry and electrochemical impedance spectra. The immobilized acetylcholinesterase (AChE), as a model, showed excellent activity to its substrate, leading to a stable AChE biosensor. Under the optimal experimental conditions, the inhibition of malathion on AChE biosensor was proportional to its concentration in two ranges, from 0.001 to 0.1 microg mL (-1) and from 0.1 to 25 microg mL (-1), with detection limit of 0.001 microg mL (-1). The simple method showed good reproducibility and acceptable stability, which had potential application in biosensor design. |
82(1,1,1,2) |