In situ solidifying liquids for medical application.

液体材料能迅速形成凝胶而不损伤自然组织，在治疗动静脉畸形（AVM）、止血和制备生物人工器官等方面有着广泛的应用前景。我们制备了各种液体材料，并使用动物模型检查其有效性。动静脉畸形：栓塞液通过将聚（甲基丙烯酸2-羟乙酯-co-甲基丙烯酸甲酯）溶解在Iopamiron中并加入少量乙醇来制备。还合成了用于栓塞的异硬脂基-2-氰基丙烯酸酯。这些新的栓塞液体没有细胞毒性，并且容易通过细而长的导管注射到AVM中以有效地闭塞AVM。止血剂：合成了N-羟基琥珀酰亚胺（NHS）活化的聚（L-谷氨酸）（PLGA）。这种NHS活化的PLGA可以在水溶液中与明胶立即形成凝胶。这一发现有力地表明，明胶和NHS-PLGA的这种组合是非常有前途的止血剂和防粘连剂，并可能取代纤维蛋白胶从人血液components.Cell包埋制备：水凝胶是由聚丙烯酰胺衍生物进行巯基合成的丙烯酰胺和N，N '-双丙烯酰胺的自由基共聚，然后通过还原共聚物中的二硫键。该水溶性共聚物用于通过在共聚物上重新形成二硫键来捕获仓鼠胰岛以产生水凝胶。当在体外检查时，从水凝胶中的胰岛的胰岛素释放持续超过1个月。

Liquid materials which can instantly form gels without damaging natural tissue will find many medical applications, such as treatment of arteriovenous malformation (AVM), stopping of bleeding and preparation of bioartificial organs. We prepared various liquid materials and examined their effctiveness using animal models.Arteriovenous malformation : Embolic liquid was prepared by dissolving poly (2-hydroxyethyl methacrylate-co-methyl methacrylate) in Iopamiron with an addition of a small amount of ethyl alcohol. Isostearyl-2-cyanoacrylate was also synthesized for emboliation. These new embolic liquid is not cytotoxic and is easily injected into the AVM through a thin, long catheter to effectively occlude the AVM.Hemostatic agent : The N-hydroxysuccinimide (NHS) activated poly (L-glutamic acid)(PLGA) was synthesized. This NHS activated PLGA could instantly form a gel with gelatin in an aqueous solution. This finding strongly suggest that this combination of gelatin and NHS-PLGA is verypromising as a hemostatic agent and adhesion-prevention agent, and may possibly replace fibrin glues prepared from human blood components.Cell entrapment : The hydrogel was produced from a polyacrylamide derivative carrying thiol groups synthesized by redical copolymerization of acrylamide and N,N'-bis acrylcytamine, followed by reduction of the disulfide bonds in the copolymer. This water-soluble copolymer was used to entrap hamster islets by re-formation of disulfide bonds on the copolymer to produce a hydrogel. Insulin release from the islets in the hydrogel continued for more than 1 month when examined in vitro.