An amperometric acetylcholine biosensor based on a conducting polymer

• Published in: International journal of biological macromolecules Vol. 59; pp. 111 - 118
• Main Authors: Kanik, Fulya Ekiz, Kolb, Marit, Timur, Suna, Bahadir, Müfit, Toppare, Levent
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.08.2013
• Subjects: Acetylcholine - chemistry; Acetylcholinesterase; Acetylcholinesterase - chemistry; Alcohol Oxidoreductases - chemistry; Biosensing Techniques; Biosensor; Conducting polymer; Electric Conductivity; Electrochemical Techniques; Electrodes; Graphite; Hydrogen-Ion Concentration; Immobilized Proteins - chemistry; Insecticides - analysis; Paraoxon - analogs & derivatives; Paraoxon - analysis; Polymers - chemistry; Thiophenes - chemistry; Water Pollutants - analysis; Conducting polymer; Acetylcholinesterase; Biosensor
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2013.04.028

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−1cm−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 (R2=0.998) was obtained.