【摘要】 传统的水凝胶支架面临伤口创伤、感染以及对缺损部位不适应等问题,从而导致支架的失效。可注射温敏水凝胶在注射前为流动的液体,通过注射器注入皮下组织或肌肉组织后,可在注射部位原位凝胶化,具有微创易治疗、可修复深层组织损伤、不破坏修复区供血等优点。通常血管内皮生长因子(VEGF)和基质细胞衍生因子-1(SDF-1)的半衰期较短,若将其装载到纳米颗粒复合凝胶中则可起缓释效果。因此实验制备了壳聚糖基水凝胶,保持壳聚糖和明胶体积比不变,通过加入不同体积的β-甘油磷酸钠,制备出不同组分的壳聚糖基温敏水凝胶体系,研究了不同凝胶的成胶时间、孔隙率以及细胞毒性;并制备了壳聚糖和岩藻聚糖的纳米颗粒,对VEGF和SDF-1进行了装载,并对纳米颗粒的粒径、电位及因子释放做了检测。结果表明壳聚糖基水凝胶具有温敏性且增加β-甘油磷酸钠的量会降低凝胶时间,凝胶电镜观察呈三维网络状,无细胞毒性;纳米颗粒粒径分布较均匀且稳定,在凝胶中有缓释效果。因此,制备安全可靠、有合适响应速度的壳聚糖基纳米复合水凝胶是提高材料性能的一种有效方式,将为今后满足不同需求的医用生物材料提供新的研究方向。更多还原

【Abstract】 The traditional hydrogel scaffolds are facing the problem of wound trauma,infection and inadaptation of the recipient site,which could lead to scaffold implantation failure.Injectable thermosensitive hydrogels will change their condition from liquid flow to gelation when the hydrogels are injected in the subcutaneous tissue or muscle tissue.They can reach the deep tissues and complete filling of the defect area in minimally invasive surgical procedures without damaging the repair area’s blood supplies.Generally,vascular endothelial growth factor(VEGF)and stromal cell derived factor-1(SDF-1)have a short half-life.The nanocomposite hydrogels will have good effects on their extended releasing,if the factors are loaded into the nanocomposite hydrogels.In this study,different components chitosan-based injectablehydrogels system wereprepared,and the gel time,the porosity and cytotoxicity of different hydrogels were studied.At the same time,chitosan/fucoidan nanoparticlesloading VEGF and SDF-1 were prepared.The size,zeta potential and the factor release of the nanoparticles were tested.The results showed that the chitosan-based injectable hydrogels are temperature-sensitive and increasing the volume ofβ-glycerphosphate will reduce the gel times.The SEM micrographs of formed hydrogels showed three-dimensional networks,and the hydrogels showed no cytotoxicity.The particle size distribution of nanoparticlesis uniform and stable,and the results showed a sustained releaseeffect of the nanoparticles in the hydrogels.Thus,itis an effective way to manufacture a safe,reliable and thermosensitive hydrogels,which will be a promising research direction for the future to meet the different needs of biomedical materials.更多还原