Study On The Preparation And Properties Of Zein/pbs Composite Nanofibrous Membrane Scaffold

In this thesis, the zein/Poly(butylene succinate)(PBS) composite nanofibrous membranescaffold with improved tensile strength were fabricated by the blend and coaxial electrospinning inorder to synchronously enhance the mechanical property of zein, and also obtain zein/PBScomposite tissue engineering scaffolds, which possess a better cytocompatibility depending onbiological evaluation, and finally extend the application field of zein in biomaterials.Zein/PBS blends with different mass ratios were prepared to fabricate composite nanofibrousmembrane scaffold by electrospinning, and the morphology, structure, thermal performance,mechanical properties and hydrophilicity of composite fibers were studied. The results showed theelectrospun spinnability of zein was improved by PBS. The average diameter of zein/PBScomposite fibers increased and the crystallinity of composite nanofibrous membrane scaffoldincreased with the addition of PBS content. The mechanical properties were improved effectively.At the same time hydrophilicity of composite nanofibrous membrane scaffold was greatlyimproved.In order to improve the properties of PBS, Multi-walled carbon nanotubes (MWNTs) wasmixed with PBS solution to prepare electrospun MWNTs/PBS composite nanofibous scaffold fordifferent tissue engineering scaffolds. The performance of PBS fibers with different contentMWNTs was researched. The results showed that MWNTs have been dispersed in PBS fibers, thediameter of the fibers decrease due to the addition of MWNTs, with the increase of MWNTs thethermal stability was enhanced. When the content of MWNTs is1.5%, it disperses well in PBSmatrix and the composite nanofibous membrane scaffold have the best failure strength and failureelongation.Sheath(zein)-core(PBS) composite nanofibrous membrane scaffold were successfully preparedby coaxial electrospinning. The effects of core and sheath concentrations and flow rate of the outerzein fluid on its morphology, structure and mechanical properties were investigated. The resultsrevealed that fixed sheath concentration, however higher or lower one can resist co-electrospinningstability.When the core concentration was6%, the composite nanofiber membrane scaffold had better mechanical properties. The composite fiber diameter increased and mechanical properties ofsheath-core structured composite fibers became more higher with increasing of sheath concentrationunder unchanged core concentration. The composite nanofibers with uniform morphology andintegrated sheath-core structure were obtained when both of the core and sheath spinning rates were0.006ml/min. After adding MWNTs into the core solution, the morphology ultrafine fibrousmembranes was well and the fiber diameter decreased, and the failure strength and thermalproperties became increased.Finally, through in vitro cell culture experiment, the cyto-biological of the five compositenanofibrous membrane scaffolds was investigated. The results showed that the L929mousefibroblasts proliferated well on zein, PBS, zein/PBS, sheath（zein）-core（PBS） and sheath（zein）-core（PBS/MWNTs） composite nanofibrous membrane scaffolds.. The five scaffolds werenon-toxic, and the cytocompatibility were fabourable. MWNTs added to core did not influence cellgrowth and proliferation. The two sheath-core ultrafine composite fibrous scaffolds had morecytocompatibility than zein/PBS composite nanofibrous memberane scaffolds. Their OD values arehigher than that of zein/PBS composite nanofibrous scaffolds, and the mechanical properties werebetter., so they have great application potential in tissue engineering scaffolds.