Effect of the degree of DVB crosslinking on the metal ion specificity of polyacrylamide-supported glycines

Metal ion specificity studies of divinylbenzene (DVB)-crosslinked polyacryl amide-supported glycines in different structural environments were investig ated. The effect of the degree of crosslinking on the specific rebinding of the desorbed metal ion was investigated towards Co(II), Ni(II), Cu(II), an d Zn(II) ions. The metal ion-desorbed resins showed specificity for the des orbed metal ion and the specificity characteristics increases with an incre asing degree of the crosslinking agent. The polymeric ligands and metal com plexes were characterized by IR, UV-visible and EPR spectra, and by SEM ana lysis. The swelling and Solvation characteristics of the crosslinked polyme rs, polymeric ligands and metal complexes, the effect of the pH dependence on metal ion binding and rebinding and the kinetics of metal ion binding an d rebinding were also followed. The complexation resulted in the downfield shift of the carboxylate peak in the IR spectral The EPR parameters are in agreement with a distorted tetragonal geometry. The Cu(II) ion-desorbed res ins selectively rebinds Cu(II) ions from a mixture of Cu(II) and Co(II) and Cu(II) and NI(II) ions. The resin could be regenerated several times witho ut loss of capacity and effective for the specific and selective rebinding of Cu(II) ions.