Ion-Imprinted Polymer-Based Receptors for Sensitive and Selective Detection of Mercury Ions in Aqueous Environment

Maimoona Yasinzai,Nazia Asghar,Usman Latif,Ghulam Mustafa,Muhammad Zahid,Dongxue Han,Peter A Lieberzeit,Ikram Ullah

doi:10.1155/2018/8972549

Abstract

Interdigital electrodes (IDE) coated with ion-imprinted polymers (IIP) as recognition materials have been tested for screening and ion quantification. For screening of receptors, three polymer systems based on styrene (Sty), N-vinylpyrrolidone (NVP), and Sty-co-NVP were examined to identify an efficient recognition system for mercury ions in an aqueous environment. Results showed that all these polymeric systems can detect analyte even in very low concentration, that is, 10 ppm. Ion-imprinted polystyrene system proved to be an ideal receptor for detecting mercury ions in solution with a detection limit of 2 ppm. The sensitivity of ion-imprinted copolymeric system was further enhanced by making its composite with graphene oxide, and estimated detection limit of composite system was around 1 ppm. Ion- imprinted Sty-co-NVP graphene composite-based sensor system exhibits 2 to 5 times higher sensor response towards templated analyte in comparison to other polymer-based sensor systems. Moreover, the composite-based sensor shows very low or negligible response to competing metal ions with similar or different oxidation states such as Zn, Mg, Na, and As metal ions.

Highlights

Heavy metals are widely distributed pollutants in aqueous environment, and these are highly toxic to humans and animals even at trace levels [1]
NVP-based Hg2+-imprinted receptor system was synthesized by using ethylene glycol dimethacrylate (EGDMA) as crosslinker
Hg(II)-imprinted polymeric- and compositebased sensor systems were fabricated by following molecular imprinting approach

Summary

Introduction

Heavy metals are widely distributed pollutants in aqueous environment, and these are highly toxic to humans and animals even at trace levels [1]. Numerous analytical methods and techniques, such as cold vapor atomic absorption spectrometry, atomic fluorescence spectrometry, and inductively coupled plasma mass spectrometry, have been intensively developed for its quantification [8,9,10]. These techniques are expensive and require trained personnel, and certain complicated processes are involved prior to final analysis. The polymerization process can be performed by reversible covalent and noncovalent interactions between monomers and imprinting molecules

Methods

Results

Conclusion