Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9743907 | Analytica Chimica Acta | 2005 | 7 Pages |
Abstract
Amperometric enzyme biosensors for the determination of acetylcholine (ACh) and choline (Ch) have been described. For the fabrication of the biosensors, N-acetylaniline (nAN) was first electropolymerized on a Pt electrode surface to be served as a permselective layer to reject interferences. Bovine serum albumin (BSA) and choline oxidase (CHOD) were co-immobilized in a zinc oxide (ZnO) sol-gel membrane on the above modified Pt electrode for a Ch sensor, or CHOD, acetylcholinesterase (AChE) and BSA immobilized together for an ACh/Ch sensor. The poly (N-acetylaniline) (pnAN) film was the first time used for an ACh/Ch sensor and found to have excellent anti-interference ability, and the BSA in the sol-gel can improve the stability and activity of the enzymes. Amperometric detection of ACh and Ch were realized at an applied potential of +0.6Â V versus SCE. The resulting sensors were characterized by fast response, expanded linear range and low interference from endogenous electroactive species. Temperature and pH dependence and stability of the sensor were investigated. The optimal ACh/Ch sensor gave a linear response range of 1.0Â ÃÂ 10â6 to 1.5Â ÃÂ 10â3Â M to ACh with a detection limit (S/NÂ =Â 3) of 6.0Â ÃÂ 10â7Â M and a linear response range up to 1.6Â ÃÂ 10â3Â M to Ch with a detection limit of 5.0Â ÃÂ 10â7Â M. The biosensor demonstrated a 95% response within less than 10Â s.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Minghui Yang, Yunhui Yang, Yu Yang, Guoli Shen, Ruqin Yu,