Polyacrylamide-phytic acid-polydopamine conducting porous hydrogel for rapid detection and removal of copper (II) ions.

In this work, a conducting porous polymer hydrogel-based electrochemical sensor has been developed for rapid detection of copper (II) ions (Cu). The polymer (termed as PAAM/PA/PDA) hydrogel is prepared through multi-interactions of the monomers dopamine (DA), acrylamide (AAM) and phytic acid (PA) under mild ambient conditions: the AAM polymerizes through free-radical polymerization, DA occurs poly coupling reaction, and PA crosslinks polydopamine (PDA) and polyacrylamide (PAAM) by hydrogen bonds. The three dimensional (3D) network nanostructured PAAM/PA/PDA hydrogel not only provides a large surface area for increasing the amount of immobilized molecules/ions, but also exhibits a good conductivity. The PAAM/PA/PDA hydrogel-based electrochemical sensor exhibits a low detection limit (1nmolL, S/N=3) and wide linear range (from 1nmolL to 1µmolL) for Cu detection in aqueous samples. Furthermore, the Cu can be sensitively detected by the electrochemical sensor in different sample matrices, indicating that the electrochemical sensor could be used to monitor Cu with reasonable assay performance in practical samples. The PAAM/PA/PDA hydrogel also exhibits a good capacity to remove Cu(231.36±4.70mgg), which is superior to those of other adsorption materials reported in the literature. The facile synthesized PAAM/PA/PDA hydrogel provides a novel and regenerable platform for monitoring and removing Cu in real samples.