Preparation And Pore Structure Control Of The Silk Fibroin/Poly (Lactic Acid-glycolic Acid) Blend Nanofibrous Membranes

Regenerated silk fibroin is a kind of natural polymer material that it has superior biologicalperformance. Based on the application of tissue engineering scaffolds and mechanicalperformance requirements, regenerated silk fibroin (SF)/poly lactic-co-glycolic acid (PLGA)blend nanofibrous membranes were successfully prepared via electrospinning and then it wastreated with Methanol. It was discussed that the different content of PLGA effected on structureand performance of nanofibrous membranes.The results showed that the blend nanofibers membranes had good surface morphology.Thediameters of the fibers were increased with the addition of PLGA. The addition of PLGA hadno influcement on the molecular structure of regenerated silk fibroin. The mechanical propertiesof blend nanofibrous membranes improved significantly and the breaking strength of thematerial was also increased to3.8MPa. Methanol makes regenerated silk fibroin have a βtransition and makes the material do not dissolve in water. After treated with methanol, thebreaking strength of the material was also increased to3.6MPa.In order to be used in tissue engineering scaffold, cells can stand inside. The adjustmentmethods of blend nanofiberous membranes pore diameter and porosity were studied in thisarticle. The diameter is the important factor that influence nanofibrous membrane,s pore size andporosity. In this paper, the electrospinning technique was used to prepare the SF/PLGA blendnanofibers membrane, and the spinning fluid flow rate and the needles were changed forprepared different pore size and porosity of the nanofibrous membrane. Field emission scanningelectron microscopy (FE-SEM), multifunctional stretcher, pore size analyzer were used tocharacterize blend nanofibrous membrane morphology, mechanical properties and pore size andporosity.Results indicated that the improving spinning flow rate or using larger inner diameterneedles could improve the pore size and porosity of nanofibrous membrane. When spinning flowrate was increased to0.06mL/min, the average pore size was increased to1.94μm. Porosity wasincreased to81%. But the tensile strength was dropped0.5MPa. When the needle diameter was increased to1.54mm, the average pore size fiber membrane was increased to3.08μm, porosityreached to85%. But the tensile strength was dropped.Changing the diameters of the fiber can regulate fiber membrane pore structure a little. Tomake a greater degree of fibrous membrane,s pore structure, the fourth chapter in this article waswet electrostatic spinning. The fibres were received in solution instead of the traditional flat.Through the method of freeze-drying, the real spongy3-D structure of the nanofiberousmembranes could be got. The results showed that this kind of structure of nanofibrousmembranes pore size and porosity reached16μm,91%respectively.