Selective Solid-Phase Extraction of Trace Copper Ions in Aqueous Solution with a Cu(II)-Imprinted Interpenetrating Polymer Network Gel Prepared by Ionic Imprinted Polymer (IIP)Technique

摘要

An Cu(II)-imprinted interpenetrating polymer network (IPN)gel of epoxy-diethylenetriamine and methacrylic acid-acrylamide-N,N'-methylene-bis-(acrylamide)was synthesized by the ionic imprint polymer (IIP)technique.The first polymer network is formed by epoxy gelation with diethylenetriamine.The other is formed by copper methacrylate co-polymerization with acrylamide and cross-linker N.N'-methylene-bis-(acrylamide).The adsorption-de-sorption characteristics of the IPN gel as a highly selective solid-phase extraction (SPE)and preconcentration adsorbent for Cu~(2+)from aqueous solution were investigated.The experimental results show that trace Cu~(2+)ions can be quantitatively enriched at pH 5 with recovery >95%.The maximum static adsorption capacity of the ion-imprinted functionalized gel adsorbent was 76mgg~(-1).Comparing with non-imprinted IPN gel,the imprinted IPN gel has higher adsorption capacity and selectivity for Cu~(2+)by the static adsorption-desorption experiment.Simultaneously,the times of adsorption equilibration and complete desorption were remarkably short.The precision (RSD)for 11 replicate adsorbent extractions of 20ngmL~(-1)Cu~(2+)was 3.4%.The established procedure was applied to two real water samples with satisfactory results.The prepared ion-imprinted IPN gel adsorbent was shown to be promising for solid-phase extraction coupled with atomic absorption spectrometry (AAS)for the determination of trace copper in real samples.In addition,the coordination interaction of Cu~(2+)and functional groups of the IPN gel adsorbent was primarily discussed by FT-IR spectra.