Dithiocarbamate Induced Catalytic Hydrogen Wave for the determination of Iron (II) in Waters and Leafy Vegetables: Experimental and Computational Approach

摘要

A simple, sensitive, selective and robust catalytic hydrogen wave method was developed by noveldithiocarbamates (ammonium 2,6-dimethyl morpholine dithiocarbamate and ammonium 3-methylpiperidine dithiocarbamate) using DC polarography. This method was based on the interaction ofIron(II) with dithiocarbamates in the presence of buffer (NH4Cl-NH4OH) at pH 6.6/6.4 to producecatalytic hydrogen currents at -1.39/-1.32V vs SCE respectively. The optimized experimentalconditions were established by investigating the pH effect, supporting electrolyte (NH4Cl-NH4OH),and concentration of ligand. Thereafter, adverse ions effect on wave height was evaluated to enhancethe selectivity of the present method. Additionally, the density functional theory calculations ofammonium 3-methyl piperidine dithiocarbamate revealed a smaller HOMO-LUMO energy gap thanammonium 2,6-dimethyl morpholine dithiocarbamates, suggesting that ammonium 3-methylpiperidine dithiocarbamates have a superior propensity to act as an electron donor to Iron(II). Thereported analytical method was successfully applied for the detection of Iron (II) in different water andleafy vegetable samples with recoveries ranging from 97-99 %.