The graft polymerization of acrylonitrile on crosslinked polyvinyl alcohol (CPVA) microspheres was performed by using cerium ammonium sulfate as initiator

and grafted microspheres CPVA-g-PAN were prepared.Subsequently

the grafted PAN was converted into poly(amidoxime) (PAO) via amidoximation reaction with hydroxylamine hydrochloride as reagent

resulting in the functional microspheres CPVA-g-PAO.The chemical structure and physicochemistry characters of CPVA-g-PAO microspheres were adequately characterized by infrared spectrum (FTIR)

scanning electron microscope (SEM) and determining zeta potential.The effects of main factors on the amidoximation transform reaction of the grafted PAN were studied with emphasis

and the adsorption property of the functional microspheres CPVA-g-PAO for some biomolecules was examined preliminarily with uric acid as a model biomolecule.The experimental results show that in the a midoximation transform reaction of nitrile groups

medium pH and reaction temperature are two main factors.For this system

the adequate pH value and temperature are 6～7 and 70℃.Under the fitting conditions

the conversion ratio of the nitrile group of the grafted PAN reaches 72% for 4 h.In a wider pH range

the zeta potential of the microspheres CPVA-g-PAO is a greater positive value.They exhibit strong adsorption ability for uric acid

a toxic endogenrsis molecule

and the adsorption capacity can get up to 95 mg/g.