Iodate Sensing Electrodes Based on Phosphotungstate-Doped-Glutaraldehyde-Cross-Linked Poly-L-lysine Coatings

Glassy carbon electrode modified with phosphotungstate-doped-glutaraldehyde-cross-linked poly-L-lysine (PLL-GA-PW) film was employed for iodate determination. The PLL-GA-PW film electrode shows excellent electrocatalytic activity towards iodate reduction with significant reduction of overpotential. Under optimized experimental conditions, a linear range from 5 x 10(-8) to 2.27 x 10(-2) M with a sensitivity of 61.75 mu A mM(-1) was obtained. Possible interfering species, in iodate determination, were evaluated and the applicability of proposed sensor for iodate estimation in table salt was also demonstrated. The PLL-GA-PW film electrode shows fast response, wider linear range, and good selectivity and stability.