Preparation And Characterization Of Electrospun P(LA-co-GA-co-MMD) Tissue Engineering Scaffolds

Excellent biodegradable materials are desired as temporary scaffolds to support the growth,proliferation,differentiation of cell and disappear gradually with the progress of guided tissue regeneration.Electrospinning technology can prepare nanofibers with high surface area and porosity to mimic the 3-D structure of extracellular matrix(ECM)and has become one efficient method to construct tissue engineering scaffolds.In this paper,we synthesized 3(S)-methyl-morpholine-2,5-dione(MMD)monomer with L-alanine and chloroacetyl chloride.Then,a series of copolymers poly(lactide-co-glycolide-co-3(S)-methyl-morpholine-2,5-dione)[P(LA-co-GA-coMMD)] with different L-lactide(LA),glycolide(GA)and MMD contents were synthesized by ring opening polymerization using stannous octoate as catalyst.The 1H-NMR and FT-IR tests show that the copolymers were synthesized successfully and the MMD contents in three kinds of copolymers were 5.5%,13.0% and 17.4%,respectively.The P(LA-co-GA-co-MMD)nanofibrous scaffolds were prepared by electrospinning technology.The morphology of scaffolds was analyzed by scanning electron microscopy(SEM),and the results showed that the fibers are smooth,regular and randomly oriented with diameter of 700±100 nm.The tensile strength and elongation at break of P(LA-co-GA-co-MMD)nanofibrous scaffolds at wet condition were in the range of 1.89-2.46 MPa and 114%-559%,respectively.The vitro degradation test showed that the weight loss of scaffolds increased significantly with the increasing content of MMD,indicating good biodegradable property of the scaffolds.The cytocompatibility of electrospun nanofibrous scaffolds was tested by human umbilical vein endothelial cells and MTT essay.It is demonstrated that the scaffolds showed low toxicity and good cytocompatibility and the cells could attach and proliferate well on P(LA-co-GA-co-MMD)scaffolds.The P(LA-co-GA-co-MMD)scaffolds benefited to excellent cell infiltration and showed good tissue response after subcutaneous implantation.These results indicated that the P(LA-co-GA-co-MMD)nanofibrous scaffolds showed good biocompatibility and could be potential candidates for vascular tissue engineering.