Chronoamperometric Determination of Sulphite Using Gold- Printed Electrode

A chronoamperometric method for the determination of sulphite ions has been developed using disposable, screen-printed gold electrodes in presence of some mediators. The used mediators include: potassium hexacyanoferrate (III), hydroxymethylferrocene, 4- (methylamino) phenol sulphate. Calibration curves exhibit a linear relationship between the electrode response and the sulphite concentration over the range from 100 M to 3.00 mM. The correlation coefficients for calibration curve was equal to 0.992. The obtained limit of detection (LOD) was 30 M. The relative standard deviations were equal to or better than 6.96 % (n=5). The interferences of various ions were studied. The used sensors are successfully applied for the determination of sulphite in tap water and agriculture drain water. It was found that the used screen-printed electrodes have its initial response after storage in dry state at room temperature up to eight months.