A highly selective voltammetric sensor for nanomolar detection of mercury ions using a carbon ionic liquid paste electrode impregnated with novel ion imprinted polymeric nanobeads.

This work reports the preparation of a voltammetric sensor for selective recognition and sensitive determination of mercury ions using a carbon ionic liquid paste electrode (CILE) impregnated with novel Hg(2+)-ion imprinted polymeric nanobeads (IIP) based on dithizone, as a suitable ligand for complex formation with Hg(2+) ions. The differential pulse anodic stripping voltammetric technique was employed to investigate the performance of the prepared IIP-CILE for determination of hazardous mercury ions. The designed modified electrode revealed linear responses in the ranges of 0.5nM-10nM and 0.08μM-2μM with a limit of detection of 0.1nM (S/N=3). It was found that the peak currents of the modified electrode for Hg(2+) ions were at a maximum value in phosphate buffer of pH4.5. The optimized preconcentration potential and accumulation time were to be -0.9V and 35s, respectively. The applicability of the proposed sensor to mercury determination in waste water samples is reported.