Biomedical Technology Wing, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Poojapura, Thiruvananthapuram-695 012, Kerala, India.
J Biomed Mater Res A. 2013 Jul;101(7):1876-87. doi: 10.1002/jbm.a.34490. Epub 2012 Nov 30.
In this work an in vitro degradable poly(ester-urethane)urea (PEUU) was synthesized using polycaprolactone diol, hexamethylene diisocyanate, and calcium salt of p-aminobenzoic acid. The synthesized polymer was characterized by (1) H-NMR and FTIR spectroscopy and viscosity studies. Scaffolds having random micro fibrous structures were fabricated from PEUU by electrospinning process. The thermal properties of the scaffold were evaluated by thermogravimetric analysis and dynamic mechanical analysis. The mechanical property evaluation showed that the scaffold possess sufficiently high tensile strength of 16 MPa. The in vitro degradation studies of the electrospun scaffold were carried out in phosphate buffer saline for 6 months. The average mass loss of the scaffold after 6 months of hydrolytic degradation was 25%. FTIR spectroscopy study confirmed the degradation of the PEUU from decrease in intensity of 1400 cm(-1) peak corresponding to ionic carboxylate group. Presence of amine group and calcium ions in the degradation medium further confirmed the degradation of the hard segment in the hydrolytic medium. The mechanical property evaluation of the scaffold indicated a gradual decrease in tensile strength and modulus whereas percentage elongation of the scaffold increases with time of in vitro degradation. The morphological evaluation of the scaffold after degradation by SEM shows evidence of broken fibers and pores in the scaffold. Preliminary in vitro cytotoxicity test demonstrated that both the material and the degradation products were noncytotoxic in nature and the material showed good proliferation to L-929 cells.
在这项工作中，使用聚己内酯二醇、六亚甲基二异氰酸酯和对氨基苯甲酸钙合成了一种可在体外降解的聚（酯-尿烷）脲（PEUU）。通过 1 H-NMR 和 FTIR 光谱以及粘度研究对合成聚合物进行了表征。通过静电纺丝工艺从 PEUU 制备具有随机微观纤维结构的支架。通过热重分析和动态力学分析评估支架的热性能。力学性能评估表明，支架具有足够高的拉伸强度 16 MPa。对电纺支架的体外降解研究在磷酸盐缓冲液中进行了 6 个月。在水解降解 6 个月后，支架的平均质量损失为 25%。FTIR 光谱研究证实了 PEUU 的降解，这是由于与离子羧酸酯基团对应的 1400 cm(-1)峰的强度降低所致。降解介质中胺基和钙离子的存在进一步证实了硬段在水解介质中的降解。支架的力学性能评估表明，拉伸强度和模量逐渐降低，而支架的伸长率随体外降解时间的增加而增加。降解后支架的 SEM 形态评估表明支架的纤维和孔出现断裂。初步的体外细胞毒性试验表明，该材料及其降解产物均无细胞毒性，并且该材料对 L-929 细胞具有良好的增殖能力。
