Analytical method for the detection and measurement of paracetamol

摘要

Method and electrode for electrolytic analysis/assay of paracetamol in liquids, especially in biological fluids (e.g. blood and serum), using a working metal electrode (especially of platinum) surrounded by two membranes -- an "inner" perm-selective one and an "outer" one of diffusion-limiting microporous material. The inner membrane is preferably a cellulose ester (especially cellulose acetate) or plasticised PVC, and is preferably 0.1 to 1.0 (my)m thick. The outer membrane is a polycarbonate, less than 10 microns thick, with a porosity less than 2 %, and is preferably first treated with a silane to increase its hydrophobic properties. The electrodes can be calibrated by treatment in a buffer solution (preferably isotonic phosphate buffer) before addition of the liquid under assay. Most conveniently, the electrode is set centrally in a polymer and surrounded by a silver ring as a reference electrode. Rapid measurement of paracetamol can be obtained from readings of the rate of current increase with time, shortly after contact with the analyte.