title: Covalently immobilized choline oxidase and cholinesterases on a methacrylate copolymer for disposable membrane biosensors.
abstract: Bienzymatic sensors for the determination of esters of choline were prepared by covalent co-immobilization of cholinesterases and choline oxidase on polymer membranes, obtained by radiation-induced copolymerization of 2-hydroxyethyl methacrylate and glycidyl methacrylate at low temperature. Optimization of the covalent attachment of choline oxidase and acetyl- or butyrylcholinesterase to copolymer was explored. The enzyme-modified polymers were applied on platinum electrodes to form amperometric sensors, based on the electrochemical detection of enzymatically developed hydrogen peroxide. Acetyl-, acetylthio-, butyryl-, and butyrylthiocholine contents in standard solutions were measured, and linear calibration curves were determined. Temperature and pH effects on the electrochemical response are described.
authors.affiliation: Ufficio Sicurezza e Prevenzione del CNR, Padova, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Doretti
authors.forename: P
authors.initials: P
authors.lastname: Gattolin
authors.forename: A
authors.initials: A
authors.lastname: Burla
authors.forename: D
authors.initials: D
authors.lastname: Ferrara
authors.forename: S
authors.initials: S
authors.lastname: Lora
authors.forename: G
authors.initials: G
authors.lastname: Palma
mesh_terms: D000429:Alcohol Oxidoreductases; D000818:Animals; D015374:Biosensing Techniques; D002802:Cholinesterases; D004563:Electrochemistry; D004800:Enzymes, Immobilized; D005069:Evaluation Studies as Topic; D006861:Hydrogen Peroxide / Q000032:analysis; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D011109:Polymethacrylic Acids; D013696:Temperature
chemical_list: D004800:Enzymes, Immobilized; D011109:Polymethacrylic Acids; D006861:Hydrogen Peroxide; D000429:Alcohol Oxidoreductases; C019888:choline oxidase; D002802:Cholinesterases