Exploiting ion-pair formation for the enhancement of electroanalytical determination of pyridoxine (B6) onto polyurethane-graphite electrodes

摘要: Abstract The present study reports some aspects of ion-pair formation between pyridoxine and dodecyl sulphate under suitable conditions pH, its application with analytical purposes. Electrochemical behavior the analite onto a graphite-polyurethane electrode was assessed by both cyclic square-wave voltammetries different (pH from 1.2 to 13.0, without surfactant), aiming mechanisms define best parameters for such determination exploiting association electroanalytical variables formation; besides these, electrochemical impedance spectroscopy also applied evaluate influence on interfacial fenomena. Best were reach voltammetry in pH 4.2 acetate buffer sweeping + 0.7 + 1.2 V ( vs. Ag|AgCl sat ) pulses 50 mV amplitude 10 mV step, frequency 10 Hz. concentration sodium optimized being optimal value constant submicelar 3 mmol L -1 . Under linear dynamic range 2 18 μmol observed, providing faster, more selective sensitive system. Interference studies carried out showing no relevant thiamine, riboflavine nicotinamide over analysis pyridoxine. system successfully commercial parenteral samples containing thiamine as purchased, further treatment.