title: An amperometric acetylcholine biosensor based on a conducting polymer.
abstract: An amperometric acetylcholine biosensor was prepared by the generation of the conducting polymer poly(4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)benzenamine) (poly(SNS-NH2)) on graphite electrodes. For pesticide detection, the enzymes acetylcholinesterase (AChE) and choline oxidase (ChO) were co-immobilized onto the conducting polymer poly(SNS-NH2) films using covalent binding technique. Electrochemical polymerization was carried out using a three-electrode cell configuration via cyclic voltammetry. Characterization of resulting acetylcholine biosensor was done in terms of optimum pH, enzyme loading, range of linear response and shelf-life. Linear range was 0.12-10mM and shelf-life 4 weeks. Sensitivity was calculated as 2.19μAmM(-1)cm(-2). The designed biosensor was tested for the determination of paraoxon-ethyl in spiked tap water samples. The results were compared with a conventional quantification method using HPLC-DAD. Linear correlation of the quantification results with both methods (R(2)=0.998) was obtained.
authors.affiliation: Department of Biotechnology, Middle East Technical University, Ankara 06800, Turkey. fulyaekiz@gmail.com
authors.forename: Fulya Ekiz
authors.initials: FE
authors.lastname: Kanik
authors.forename: Marit
authors.initials: M
authors.lastname: Kolb
authors.forename: Suna
authors.initials: S
authors.lastname: Timur
authors.forename: Müfit
authors.initials: M
authors.lastname: Bahadir
authors.forename: Levent
authors.initials: L
authors.lastname: Toppare
mesh_terms: D000109:Acetylcholine / Q000737:chemistry; D000110:Acetylcholinesterase / Q000737:chemistry; D000429:Alcohol Oxidoreductases / Q000737:chemistry; D015374:Biosensing Techniques; D004553:Electric Conductivity; D055664:Electrochemical Techniques; D004566:Electrodes; D006108:Graphite; D006863:Hydrogen-Ion Concentration; D055767:Immobilized Proteins / Q000737:chemistry; D007306:Insecticides / Q000032:analysis*; D010261:Paraoxon / Q000031:analogs & derivatives* / Q000032:analysis; D011108:Polymers / Q000737:chemistry*; D013876:Thiophenes / Q000737:chemistry*; D014873:Water Pollutants / Q000032:analysis*
chemical_list: D055767:Immobilized Proteins; D007306:Insecticides; D011108:Polymers; D013876:Thiophenes; D014873:Water Pollutants; C121104:ethylparaoxon; D006108:Graphite; D000429:Alcohol Oxidoreductases; C019888:choline oxidase; D000110:Acetylcholinesterase; D000109:Acetylcholine; D010261:Paraoxon