title: An acetylcholinesterase biosensor based on platinum nanoparticles-carboxylic graphene-nafion-modified electrode for detection of pesticides.
abstract: A sensitive amperometric acetylcholinesterase (AChE) biosensor based on platinum nanoparticles (Pt NPs), carboxylic graphene (CGR), and nafion (NF)-modified glassy carbon electrode (GCE) has been developed. The Pt NPs-CGR-NF nanocomposites with excellent conductivity, catalysis, and biocompatibility offered an extremely hydrophilic surface for AChE adhesion. Chitosan (CS) was used as cross-linker to immobilize the AChE on Pt-CGR-NF-modified GCE. NF was used as a protective membrane of the AChE biosensors. The AChE biosensor showed favorable affinity to acetylthiocholine chloride (ATCl) and could catalyze the hydrolysis of ATCl with an apparent Michaelis-Menten constant value of 148μM. Under optimum conditions, the biosensor detected methyl parathion in the linear range from 1.0×10(-13) to 1×10(-10)M and from 1.0×10(-10) to 1×10(-8)M with a detection limit of 5×10(-14)M and detected carbofuran in the linear range from 1.0×10(-12) to 1×10(-10)M and from 1.0×10(-10) to 1×10(-8)M with a detection limit of 5×10(-13)M. The biosensor exhibited good sensitivity, acceptable stability, and reproducibility, thus providing a promising tool for analysis of enzyme inhibitors.
authors.affiliation: School of Chemical Science and Engineering, Yunnan University, Kunming 650091, China.
authors.forename: Long
authors.initials: L
authors.lastname: Yang
authors.forename: Guangcan
authors.initials: G
authors.lastname: Wang
authors.forename: Yongjun
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000110:Acetylcholinesterase / Q000737:chemistry / Q000378:metabolism*; D015374:Biosensing Techniques; D004566:Electrodes; D004785:Environmental Pollutants / Q000737:chemistry; D005465:Fluorocarbon Polymers / Q000737:chemistry*; D006108:Graphite / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D010575:Pesticides / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D004785:Environmental Pollutants; D005465:Fluorocarbon Polymers; D010575:Pesticides; C040402:perfluorosulfonic acid; D010984:Platinum; D006108:Graphite; D000110:Acetylcholinesterase