新型改性聚乳酸及其亲/疏水性研究

A New Familyof Modified Poly(D,L)-lactic Acids and Their Hydrophilicity/Hydrophobicity

合成了基于马来酸酐改性聚乳酸 (MPLA)和丁二胺的新型改性聚乳酸 (BM PLA) ,旨在提高聚乳酸的亲水性 ,克服聚乳酸和MPLA在降解过程中的酸性 ,并为进一步引入多肽和胶原等生物信号分子提供活性基团。通过红外光谱测定到了丁二胺已成功引入到MPLA中。利用接触角和吸水率评价了BMPLA的亲 /疏水性变化 ,表明丁二胺改性所得BMPLA的亲水性相对于PDLLA和MPLA已大大改善 ,测定了材料在 12周降解过程中的 pH变化 ,表明丁二胺改性聚乳酸不表现酸致自加速降解特征 ,未出现pH陡降现象 ,已完全克服了聚乳酸和马来酸酐改性聚乳酸降解过程中的酸性。上述研究结果提示 ,丁二胺改性聚乳酸是一族新型的具有优良亲水性和良好降解行为的组织工程材料 ,预示着它可望具有优良的细胞亲和性 ,在组织工程中具有重要的应用潜力。

A new family (BMPLA) of modified PDLLAs based on butanediamine modified MPLA (maleic anhydride modified PDLLA) was synthesized, attempting to improve the hydrophilicity of PDLLAs, overcome their acidity and change their bulk degradation behavior during degradation and provide reactive groups of -NH2 and -COOH for introducing biosignal molecules such as collagen, peptide into PDLLAs to impart biospecficity. IR spectra were used to characterize MPLAs and BMPLAs. The results indicated the successful introduction of butanediamine into MPLA. The hydrophilicity/hydrophobicity of BMPLAs, MPLAs and PDLLAs was investigated through static water contact angles and water uptake. Both static water contact angles and water uptake showed that the hydrophilicity of BMPLA has been greatly improved. Furthermore, BMPLA's pH didn't exhibit such dramatic and sharp decrease as those of PDLLA and MPLA.