Synthesis of imprinted polymer material with palladium ion nanopores and its analytical application

Ion imprinted polymer (IIP) materials with nanopores were prepared by formation of ternary complex of palladium imprint ion with dimethylglyoxime (DMG) and 4-vinylpyridine (VP, functional monomer) and thermally copolymerizing with styrene (crosslinking monomer) and divinylbenzene (cross linker) and 2,2'-azobisisobutyronitrile as initiator. The synthesis was carried out with cyclohexanol as porogen and subsequently leached with 50% (v/v) HCl to obtain leached IIP particles. These leached IIP particles can now pick up palladium ions from dilute aqueous solutions. The optimal acidity for quantitative enrichment was 0.2-0.4N HCl and eluted completely by stirring for 15 min with 2 x 10 ml of 50% (v/v) HCl The palladium ion imprinting polymer gave 100 times higher distribution ratio than ion recognition (blank) polymer (IRP). Further, percent extraction, distribution ratio and selectivity coefficients of palladium and other selected inorganic ions using IRP and IIP particles were determined and compared. Five replicate determinations of 50 mug of palladium in 11 of solution gave a mean absorbance of 0.200 with a relative standard deviation of 2.12%. The detection limit corresponding to three times the standard deviation of the blank was 2.5 mug of palladium/l. (C) 2003 Elsevier B.V. All rights reserved.