Article ID Journal Published Year Pages File Type
7682272 Talanta 2013 5 Pages PDF
Abstract
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 +250 mV, a 1 mM 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 20 µM. 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.
Related Topics
Physical Sciences and Engineering Chemistry Analytical Chemistry
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