Synthesis, characterization and application of a novel ion-imprinted polymer based voltammetric sensor for selective extraction and trace determination of cobalt (II) ions

A novel Co2+ selective sensor based on the ionic imprinted polymer (IIP) nanobeads was constructed and applied for differential pulse cathodic stripping voltammetric determination of cobalt ions. The IIP nanobeads was fabricated by polymerization of acryl amide (AAM) as functional monomer, N,N methylenebisacryl amide (NNMBA) as cross linker and ammonium persulphate (APS) as initiator, around the complex of Co2+ − 8-hydroxyquniline linked to the casted magnetic nanoparticles at the surface of glassy carbon electrode. Removal of the Co (II) from the imprinted polymer and creation of cavities for hosting Co (II) was proved by comparison of the response of IIP/MNPs-oxine/GCE to template with that of non-imprinted polymer (NIP/MNPs-oxine/GCE). The effect of various factors on the response behavior of the electrode were investigated and optimized. The introduced sensor showed two linear ranges of 0.5 to 20 and 20 to 500 nM with detection limit of 0.1 nM (S/N = 3). The sensor was successfully applied for low level determination of cobalt in different real samples.