Cytocompatibility Evaluation Of A Novel PEG-Imine Derivate Copolymerization With Polylactide

The modified polylactide material is considered as a hot topic in the research oftissue engineering materials, which characters are better than polyactide. It is provedthat the introducted PEG can improve the performance of PLA significantly in a largenumber of papers. We introduced PEG to the polylactide, PAP was prepared through thechemical reaction of ATPEG and PMDA, further reaction PAP-PLA was get finally.Furthermore, the hydrophilicity/hydrophobility of PAP-PLA is characterized by thestatic water contact angle and water absorption; cytocompatibility of PAP and PMA arestudied, so does the PAP-PLA. The osteoblasts morphology, attachment and spreading,proliferation, differentiation and mineralization ability were detected to evaluate thecytocompatibility of PAP-PLA copolymers. Main contents and conclusions of this studyare as follows:①The result of static water contact angle and water absorption show that thehydrophilicity of PAP-PLA copolymer is much better and more appropriate than PLA.The hydrophilicity/hydrophobility of PAP-PLA copolymer could be adjusted throughchanging the proportion of blocks which lay the foundation for the application ofPAP-PLA copolymer in the field of tissue engineering. The structrue and groups ofPAP-PLA copolymer are common, which have a good cytocompatibility. The researchof polyimide in biological field is limited, so the introduction of polyimide block is theinnovation in this paper. But the cytocompatibilities of PAP and PMA in degradationproducts are to be characterized.②The identification experiment of primary osteoblasts shows that the obtainedprimary osteoblasts which have a good morphology, high activility of proliferation anddifferentiation and mineralization ability, is suitable for related cell experiment.③The cytocompatibility of new block PAP get in degradation are characterizedthrough extraction method in this research. The result shows that the osteoblastsmorphology, proliferation, differentiation and mineralization ability of cells is normalwith control groups in different times after being incubating by the extracted liquid fromPAPI, which indicated that the material have a good cytocompatibility.④The cytocompatibility of PMA get in degradation are also characterizedthrough extraction method in this research. PMA is generated from the completedegradation of PAP and two groups PAP-PLA, and PMA is introduced into the medium for incubating the osteoblasts. The differentiation ability of cells dealt with PMA fromPAP is droped lightly compared with the controlled groups, but the trend of proliferationis same. No obvious difference was found between the groups of PAP-PLA andcontrolled groups in morphology, proliferation, differentiation. The above results showthat the block PAPI and PMA get in degradation of PAP-PLA have little cytotoxicityand good cytocompatiability.⑤The results of cell attachment and spreading morphology on the PAP-PLAmembrane show that over hydrophilicity or hydrophobility surface is not suitable forcell adhesion. The hydrophilicity and hydrophobility of PAPD4/20and PAPD4/25aremoderate and suitable for cell adhesion and spreading, but PAPD4/15and PLA are notideal relatively.⑥The result of cell proliferation on the PAP-PLA membrane shows that the rateof cell proliferation is higher when cells are incubated on PAPD4/20and PAPD4/25than on PLA, the situation of cell proliferation is good when cells are incubated onPAP-PLA. The trend of cell proliferation on the all materials is rising.⑦The results of cell differentiation and mineralization show that the PAP-PLAcopolymers are more suitable for cell differentiation, cell mineralization and collagensecretion than PLA.PAP-PLA copolymer has an excellent cytocompatiability, the appropriateintroduction of PAP improve the cytocompatibility of PLA, it is positive for theapplication of modified PLA on the tissue engineering.