Amino Acid Modification Of Micro-nanofibers And Its Adsorption Performance Of Bilirubin

Bilirubin is an endogenous toxin.High concentration of bilirubin in plasma can result in biliary cirrhosis and may cause permanent brain injury or death.Therefore,it is very important to effectively remove bilirubin.Affinity membrane separation is a new bioseparation technology,which combines the advantages of membrane separation and affinity chromatography,and is widely used in the process of bioseparation.To improve the flux and adsorption capacity of affinity membrane,a novel affinity adsorption material based on micro-nanofiber nonwoven was designed and developed,which provides a new way for the adsorption separation of bilirubin.Three kinds of micro-nanofibers were designed and fabricated in this paper.(1)The PET/PA6 segmented pie bicomponent spunbonded nonwoven(PET/PA6 SBSNW)possessed large flux and was formed by staggered arrangement of microfibers.There are a large number of pore channels between the fibers.The bilirubin adsorption capacity of PET/PA6 SBSNW reached 388.69 mg/g through surface modification of ethylenediamine and glutaraldehyde,and amino acids immobilization.(2)The PVDF nanofibers membrane(PVDFNM)was fabricated by solution blowing and was composed of three-dimensional crimped' fiber,and' its porosity reached 92.8%,which aimed to develop smaller diameter and higher specific surface area of adsorbent.The PVDFNM exhibited adsorption performance and its bilirubin adsorption capacity reached 393.95 mg/g by surface modification of the hydroxyethyl cellulose and epichlorohydrin,and coupling lysine.(3)PEI/PVDF shell-core nanofibers membrane(PEI/PVDF)was prepared by coaxial solution blowing based on the PEI containing multi-amino and membrane properties of PVDF,and its porosity can reach 85.6%.To simplify the subsequent modification,the multifunctional polymer can be directly spun to obtain the desired adsorbent material.After PEI/PVDF crosslinked by glutaraldehyde,the bilirubin adsorption capacity reached 372.87mg/g.To further increase the adsorption capacity,lysine affinity ligand was immobilized on the membrane surface and its bilirubin adsorption capacity reached 387.69mg/g.The paper provides a certain theoretical basis for the micro-nanofibers affinity materials applying to adsorption of bilirubin,and it is great significance for the study and development of novel affinity adsorbent that possesses high-porosity,high flux,low pressure drop,high adsorption efficiency and adsorption capacity.