Prepare Novel Biomaterials By Coaxial Electrospinning

1.Core-sheath Fe3O4-cellulose/heparin fibers were prepared by coaxial electrospinning from a nonvolatile,nonflammable ionic liquid(IL)solvent,1-methyl-3-methylimidazolium acetate([EMIM][Ac]).The iron was isolated to the core of the fiber to prevent iron toxicity.This iron core allows the fibers and fiber mats to be magnetically manipulated in either their wet or dry states.The heparin/cellulose in a non-leachable polymer blend and does not require the use of chemical cross-linking for stabilization.The heparin is externally accessible and biologically active.These anticoagulant,magnetically manipulatable biocompatible fibers and mesh have a potential application for the construction of ex vivo and in vivo medical devices.2.Core-shell fibers of PCL(shell)and PGS(core)were prepared using wet-wet coaxial electrospinning.Then the heparin was immobilized on the surface of PCL/PGS scaffold.Fabricated scaffolds were evaluated for their chemical,mechanical and biological properties.The core shell structure of PCL with PGS allow controlled degradation of the scaffold and also with tunable mechanical properties.Slowly degrading PCL will provide structural integrity and mechanical support while the fast degrading PGS component will increase the elasticity,maintaining the mechanical properties of the tissue engineered construct.The PGS–PCL scaffolds showed tunable mechanical properties that young’s modulus changed from 5.6MPa to 15.7MPa,ultimate tensile stress changed from 2.0MPa to 2.9MPa,and elongation changed from 291.4% to 906.8%.The addition of PGS and the grafted of heparin improved cell attachment and proliferation of human umbilical vein endothelial cells(HUVECs).The scaffolds provide the potential applications in tissue-engineering.