Screen-printed electrode based on AChE for the detection of pesticides in presence of organic solvents

• Published in: Talanta (Oxford) Vol. 57; no. 1; pp. 169 - 176
• Main Authors: Andreescu, Silvana, Noguer, Thierry, Magearu, Vasile, Marty, Jean-Louis
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 22-04-2002; Oxford Elsevier
• Subjects: Acetylcholinesterase; Analytical chemistry; Applied sciences; Biological and medical sciences; Biosensors; Biotechnology; Chemistry; Disposable; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General, instrumentation; Global environmental pollution; Inhibition; Methods. Procedures. Technologies; Organic phase biosensor; Pesticide; Pollution; Screen-printed electrodes; Various methods and equipments; Disposable; Inhibition; Pesticide; Acetylcholinesterase; Screen-printed electrodes; Organic phase biosensor; Performance evaluation; Enzyme; Pesticides; Esterases; Chemical sensor; Aminophenols; Carboxylic ester hydrolases; Serigraphy; Electrodes; Organic solvent; Pollution; Biosensor; Detection limit; Hydrolases; Environment; Enzymatic reaction
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/S0039-9140(02)00017-6

A screen-printed biosensor for the detection of pesticides in water miscible organic solvents is described based on the use of
p-aminophenyl acetate as acetylcholinesterase substrate. The oxidation of
p-aminophenol, product of the enzymatic reaction was monitored at 100 mV vs. Ag/AgCl screen-printed reference electrode. Miscible organic solvents as ethanol and acetonitrile were tested. The acetylcholinesterase (AChE) was immobilised on a screen-printed electrode surface by entrapment in a PVA-SbQ polymer and the catalytic activity of immobilised AChE was studied in the presence of different percentages of organic solvents in buffer solution. The sensor shows good characteristics when experiments were performed in concentrations of organic solvents below 10%. No significant differences were observed when working with 1 and 5% acetonitrile in the reaction media. Detection limits as low as 1.91×10
−8 M paraoxon and 1.24×10
−9 M chlorpyrifos ethyl oxon were obtained when experiments are carried out in 5% acetonitrile.