Development of ion-imprinted polymers for the selective extraction of Cu(II) ions in environmental waters

Pengchao Cao; Valérie Pichon; Catherine Dreanno; Kada Boukerma; Nathalie Delaunay

doi:10.1016/j.talanta.2023.124295

Development of ion-imprinted polymers for the selective extraction of Cu(II) ions in environmental waters

Talanta. 2023 May 1:256:124295. doi: 10.1016/j.talanta.2023.124295. Epub 2023 Jan 20.

Authors

Pengchao Cao¹, Valérie Pichon², Catherine Dreanno³, Kada Boukerma³, Nathalie Delaunay⁴

Affiliations

¹ Department of Analytical, Bioanalytical Sciences, and Miniaturization, UMR 8231 Chemistry, Biology and Innovation, ESPCI Paris, PSL Research University, CNRS, 10 rue Vauquelin, 75005 Paris, France; Laboratoire Détection, Capteurs et Mesures, Ifremer, Centre Bretagne, Technopole pointe du diable, 29280 Plouzané, France.
² Department of Analytical, Bioanalytical Sciences, and Miniaturization, UMR 8231 Chemistry, Biology and Innovation, ESPCI Paris, PSL Research University, CNRS, 10 rue Vauquelin, 75005 Paris, France; Sorbonne University, 75005 Paris, France.
³ Laboratoire Détection, Capteurs et Mesures, Ifremer, Centre Bretagne, Technopole pointe du diable, 29280 Plouzané, France.
⁴ Department of Analytical, Bioanalytical Sciences, and Miniaturization, UMR 8231 Chemistry, Biology and Innovation, ESPCI Paris, PSL Research University, CNRS, 10 rue Vauquelin, 75005 Paris, France. Electronic address: nathalie.delaunay@espci.fr.

PMID: 36709709
DOI: 10.1016/j.talanta.2023.124295

Abstract

Several ion-imprinted polymers (IIPs) were synthesized via bulk polymerization with Cu(II) as template ion, methacrylic acid as functional monomer, ethylene glycol dimethacrylate as crosslinking agent, and azobisisobutyronitrile as initiator in acetonitrile or methanol as porogen solvent. Non-imprinted polymers (NIPs) were similarly synthesized but without Cu(II). After grounding and sieving, the template ions were removed from IIPs particles through several cycles of elimination in 3 M HCl. All NIPs were equally subjected to this acid treatment with the exception of one NIP, called unwashed NIP. The resulting IIP/NIP particles were packed in solid phase extraction (SPE) cartridges for characterization. The SPE protocol was designed by optimizing a washing step following the sample percolation to eliminate potential interfering ions prior to the elution of Cu(II), all fractions analyzed by inductively coupled plasma mass spectrometry. The best IIP showed a high specificity (recovery of Cu(II) vs. interfering ions) and a good selectivity (retention on IIP vs. NIP). Its adsorption capacity was determined to be 63 μg g^-1. Then, a volume of 50 mL was percolated with 30 mg of IIP, thus giving rise to an enrichment factor of 24. Finally, applications to real samples (mineral and sea waters) were successfully performed. In addition, Brunauer-Emmett-Teller analyses showed that the surface area of the washed NIP was almost double that of the unwashed one (140.70 vs. 74.49 m² g^-1), demonstrating for the first time that the post-treatment of a NIP after its synthesis may have a significant impact on its porous structure, and thus need to be more precisely detailed by authors in the future papers.

Keywords: Copper; Environmental water; ICP-MS; Ion-imprinted polymer; Solid-phase extraction.