Adsorption Property of Novel Composite Material PEI/SiO_2 for Bilirubin

Polyethylenimine(PEI) was grafted on silica gel particle surface with γ-chloropropyltrimethoxysilane as the coupling agent,and novel composite adsorption material PEI/SiO2 for biomedical application was prepared.The effect of pH,ionic strength of the medium and the bound amount of PEI on PEI/SiO2 on the adsorption quantity of PEI/SiO2 for bilirubin was examined.The static adsorption experiment results show that PEI/SiO2 has a strong adsorption ability for Bilirubin.The PEI macromolecules on silica particles can produce a strong adsorption effect for bilirubin by means of electrostatic interaction.The isothermal adsorption obeyed the Freundlich equation,and the equilibrium adsorption amount reached 13.17 mg/g as the preliminary concentration of bilirubin was 0.590 g/L.The pH value of the aqueous solution has a great effect on the adsorption property of PEI/SiO2.In a near neutral solution(pH=6),there was a maximum adsorption amount,and in acidic and basic solutions,the adsorption actions were all weak.