Mawad Damia, Martens Penny J, Odell Ross A, Poole-Warren Laura A
Graduate School of Biomedical Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia.
Biomaterials. 2007 Feb;28(6):947-55. doi: 10.1016/j.biomaterials.2006.10.007. Epub 2006 Nov 3.
Biocompatible, degradable hydrogel systems that can cure in situ following injection as a liquid are useful as a base for tissue engineering and drug delivery. In this study, poly (vinyl alcohol) (PVA) polymers were modified with degradable crosslinkers and formulated for either ultraviolet (UV) light initiation or chemical initiation using an oxidation/reduction (redox) curing method. A major objective was to compare the properties of degradable PVA hydrogels formed via two routes of curing. The effect of macromer concentration, degree of hydrolysis and functional group density on the degradation profiles was investigated. Also, since the hydrogels have been designed to be injected as a liquid for in situ curing, the effect of modified macromer solutions and degradation products on cell growth was investigated. Total degradation times ranged from approximately 20 days up to 120 days and increased in direct proportion with percent macromer. Initiation method (UV or redox) did not significantly impact on time for total degradation. While aqueous solutions of the modified macromer induced some cell growth inhibition, mainly associated with oxidative solutions, degradation products showed relatively low cell growth inhibition. Degradable PVA hydrogels tailored to produce networks with various degradation profiles can be cured by redox initiation and have potential as injectable polymers for soft-tissue engineering and drug delivery.
具有生物相容性、可降解的水凝胶体系在注射时可作为液体原位固化，可用作组织工程和药物递送的基础材料。在本研究中，用可降解交联剂对聚乙烯醇（PVA）聚合物进行改性，并采用氧化/还原（氧化还原）固化方法，通过紫外线（UV）光引发或化学引发进行配方设计。一个主要目的是比较通过两种固化途径形成的可降解PVA水凝胶的性能。研究了大分子单体浓度、水解度和官能团密度对降解曲线的影响。此外，由于水凝胶被设计为作为液体注射进行原位固化，因此研究了改性大分子单体溶液和降解产物对细胞生长的影响。总降解时间约为20天至120天，并与大分子单体百分比成正比增加。引发方法（UV或氧化还原）对总降解时间没有显著影响。虽然改性大分子单体的水溶液会引起一些细胞生长抑制，主要与氧化溶液有关，但降解产物显示出相对较低的细胞生长抑制。通过氧化还原引发可固化定制的具有各种降解曲线网络的可降解PVA水凝胶，具有作为软组织工程和药物递送的可注射聚合物的潜力。
