Peng Henry T, Shek Pang N
Defence Research and Development Canada - Toronto, Toronto, ON, Canada.
J Mater Sci Mater Med. 2009 Aug;20(8):1753-62. doi: 10.1007/s10856-009-3721-5. Epub 2009 Apr 4.
We report the preparation of in situ-forming hydrogels, composed of oxidized dextran (Odex) and amine-containing polymers, for their potential use as a wound dressing to promote blood clotting. Dextran was oxidized by sodium periodate to introduce aldehyde groups to form hydrogels, upon mixing in solution with different polymers containing primary amine groups, including polyallylamine (PAA), oligochitosan and glycol chitosan. A series of experiments were conducted to identify the optimum gelation condition for the Odex-PAA system. The polymer concentration appeared to have a major effect on gelation time and the polymer weight ratio affected the resulting gel content and swelling. Other influencing factors included pH of the buffer used to dissolve each polymer, PAA molecular weight, and the type of individual material. The latter also contributed significantly to gel content and swelling. Thromboelastography was used to examine the effects of the in situ gelation on blood coagulation in vitro, where the Odex-PAA combination was found to be most pro-hemostatic, as indicated by a decrease in clotting time and an increase in clot strength. The results of this study demonstrated that in situ-forming hydrogels could promote clotting in vitro; however, further studies are required to determine if the same hydrogel formulations are effective in controlling hemorrhage in vivo.
我们报道了由氧化葡聚糖（Odex）和含胺聚合物组成的原位形成水凝胶的制备，其有潜力用作促进血液凝固的伤口敷料。葡聚糖用高碘酸钠氧化以引入醛基，在与含伯胺基的不同聚合物（包括聚烯丙胺（PAA）、低聚壳聚糖和乙二醇壳聚糖）在溶液中混合时形成水凝胶。进行了一系列实验以确定Odex - PAA体系的最佳凝胶化条件。聚合物浓度似乎对凝胶化时间有主要影响，聚合物重量比影响所得凝胶含量和溶胀。其他影响因素包括用于溶解每种聚合物的缓冲液的pH值、PAA分子量以及单个材料的类型。后者对凝胶含量和溶胀也有显著贡献。使用血栓弹力图来检查原位凝胶化对体外血液凝固的影响，其中发现Odex - PAA组合最有利于止血，表现为凝血时间缩短和凝块强度增加。本研究结果表明原位形成水凝胶可促进体外凝血；然而，需要进一步研究以确定相同的水凝胶配方在体内控制出血是否有效。
