Screen-printed biosensor based on the inhibition of the acetylcholinesterase activity for the determination of codeine

• Published in: Talanta (Oxford) 2013-07, Vol.111, p.8-12
• Main Authors: Asturias-Arribas, Laura, Asunción Alonso-Lomillo, M., Domínguez-Renedo, Olga, Julia Arcos-Martínez, M.
• Format: Article
• Language: English
• Subjects: Acetylcholinesterase; Acetylcholinesterase - metabolism; Biosensing Techniques - instrumentation; Biosensing Techniques - methods; Biosensors; Calibration; Carbon; Codeine; Codeine - analysis; Codeine - urine; crosslinking; dimerization; Electrochemical Techniques - instrumentation; Electrochemical Techniques - methods; electrochemistry; Electrodes; Electrolytes; Enzymatic biosensor; enzymatic reactions; Enzyme Assays - methods; Enzymes, Immobilized - metabolism; Humans; Inhibition; Kinetics; metabolites; oxidation; Reproducibility; Reproducibility of Results; Screen-printed electrodes; solutions; Tablets - chemistry; Tetrathiafulvalene; Urine
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2013.03.042

The current paper presents the chronoamperometric determination of codeine using screen-printed carbon electrodes that incorporate tetrathiafulvalene in the matrix of the working electrode, as mediator, and cross-linked acetylcholinesterase. Applying a potential of +250mV, a 1mM solution of acetylthiocholine in electrolyte solution pH 7 gives an oxidation signal due to the dimerization of its metabolite after the reaction with the enzyme. This electrochemical signal is decreased by consecutive additions of a solution of codeine, which allows the performance of curves of calibration for the validation of this electrochemical method, giving a reproducibility of 3.31% (n=6) and a capability of detection of 20µM. This type of inhibition has been studied by means of a Lineweaver–Burk plot. Additionally, the developed biosensor was used for the determination of the quantity of codeine in pharmaceutical commercial tablets and urine samples. •An acetylcholinesterase based biosensor has been developed for codeine determination.•TTF has been screen-printed at the electrode surface and used as mediator.•The enzyme has been cross-linked onto the surface of TTF-SPCEs.•The developed procedure allows working at 250mV, avoiding interferences.•The biosensor has been successfully applied to the analysis of Codeisan® samples.