Abstract
New potentiometricmembrane sensor determination of warfarin sodiumin pharmaceutical samples
Author(s): YehyaKamal, Al-bayati, MaysamAyadHussainSensitive and fast-responding potentiometric sensors are described for the determination of warfarin sodium. They consist of PVC matrix membranes containing the drug- phosphomolybdate ionophore complexes as electroactive materials and Tetrahydrofuran as a solvent mediator used various plasticizers: oleic acid (OA), tri-n-butylphosphate(TBP), Nitrobenzen (NB), Acetophenone (AP) and di-octyl phthalate (DOPH).. Linear dynamic response range between 1 × 10-1 and 1 × 10-5 M with Nernstian slopes of 21.3–31.6 mV/decade concentration and a detection limit of (7×10-6 - 2× 10-5) M are obtained, correlation coefficient of 0.9969 and 0.9998, the lifetime was (7-35) days respectively.Awide range of inorganic anions, amino acid and drag excipients do not interfere. Titration of the drugs with a standard phosphomolybdate solution using various sensors in conjunction with an Ag-AgCl working electrode displays S-shaped titration curves with sharp potential breaks at stoichiometric 16:2 (drug : phosphomolybdate) reaction. The proposed electrodes were successfully applied to the determination of warfarin in various pharmaceutical preparations are presented and compared. Several advantages over the pharmacopoeial methods and other techniques in current use are offered by the proposed technique.
