Research In The Preparation Of Core-shell PLCL-SF Fiber By Coaxial Electrospinning Technology

Nano-micron fiber scaffolds which is made from electrospinning technology havethe feature of small fiber diameter, high specific surface area and high porosity, whichare very helpful to promote cell adhesion and proliferation, has been considered as idealtissue engineering scaffolds. In recent years, the coaxial electrospinning technologydevelops fast because of core-shell fibers which made from it have unique materialproperty. SF and PLCL were used as the shell materials and core materials and in thispaper, for the preparation of ultrafine electrospinning membrane of core-shell structure(referred to as C-SF/PLCL); this not only can use the good biocompatibility of SF, butalso can use the PLCL’s good mechanical property.Using scanning electron microscope (SEM) observed that the good morphology ofultrafine fiber through coaxial electrospinning technology, transmission electronmicroscope (TEM) showed that the ultrafine fiber which is made through coaxialelectrospinning technology has core-shell structure. By electronic excitation energyspectrum analysis and the relevant calculation， It is showed that there is a higherproportion of core-shell structure in the C-SF/PLCL electrospinning membrane. Whenthe solvent to HFIP of silk fibroin as a shell, using HFIP: CH2Cl2=8:2as the core layerPLCL solvent, shell/core layer viscosity ratio of2.5/2.7, the flow ratio of1.8/0.6,spinning distance is12cm, under the condition of8-12kV electric field, it can formstable Taylor cone to successfully produce fiber membrane with core-shell structure.Results of X-ray diffraction and infrared spectroscopy showed that SF componentwhich in electrospinning membrane has a certain amount of silk1structure, its sizeshrinks after dealing with ethanol, and the condensed structure obviously changestowards silk II structure; PLCL component before and after alcohol dealing withoutobvious changes. After ethanol SF and the PLCL electrospinning fiber membranes areinsoluble in water. C-SF/PLCL fiber membrane which is made through coaxialelectrospinning technology has stronger breaking strength and breaking elongation than SF, which can significantly improve the mechanical property of electrospinning silkfibroin fiber membrane.By cell cultures in vitro, the growth status of cell EA.hy926under differentelectrospinning membranes is studied. The results of MTT analysis showed thatcytoactive between C-SF/PLCL electrospinning membrane and SF electrospinningmembrane is similar, slightly higher than in the SF/PLCL blend electrospinningmembrane, but obviously above the PLCL electrospinning membrane. Through resultsof scanning electron microscope (SEM), laser scanning confocal microscope (LSCM)observation show EA.hy926cells can closely adhere on the surface of four kinds of SF,PLCL, B-SF/PLCL, and C-SF/PLCL electrospinning membranes, they are fullyextended, normal, closely linked to each other, and cell number which is graduallyincreasing with time. Due to SF component having good biocompatibility, C-SF/PLCLelectrospinning membrane relative to the other three electrospinning membrane, celladhesion, spreading, growth and proliferation on the C-SF/PLCL electrospinningmembrane are similar to SF, B-SF/PLCL electrospinning membrane, but much betterthan the PLCL electrospinning membrane.Such a good property for the two-component fiber, which consisting ofthree-dimension material in blood vessel and nerve tissue repair bracket provides thepotential for applications such as possible and has value of exploration and develop.