“章鱼触角”膨润土/高分子快速高效止血材料的可控制备及止血机制

Developing a rapidly and efficiently hemorrhage material(REHM) is one of the common concerned hot topics in chemistry, medicine and materials fields. Based on the bentonite, a special resource in GuangXi province, we have synthesized a modified bentonite which has many functional branched chains on its surface. Similar to the octopus' suckers, those branched chains could catch the sodium polyacrylate (SPA) molecules chains firmly onto the sheets of bentonite when it was compounded with SPA. As a result, the significantly enhanced interfacial interaction could endow the hydrid gel excellent mechanical properties and water-uptake/water-handling abilities. We called this functional bentonite as “bentonite with octopus' suckers”(BtOS). Then “bentonite with octopus' tetancles”(BtOT) was prepared when “a long rope” was grafted between the bentonite and sucker. The performance of hybrid gel was further improved because the re-aggregation of bentonite was reduced owing to "tentacles" and the physical entangling exited in"tentacles" and molecular chains. Additionally, it is easy to tune the species of the suckers/tentacles and length of tentacles on the Bt to satisfy the requirements in various polymer composite systems. In this project, from the view of the conception that one plus one is greater than two, we will design and prepare a REHM based on BtOS, chitosan，SPA (if necessary, dopa or gelatin may be added). The influences of phase structure, interfacial properties and other microstructure on the hemostasis, antibiosis and other macroscopic performances will be studied, as well as the mechanism of hemostasis. We will apply for certification of CFDA on the REHM . This project will help to introduce the bentonite industry into a new filed in GuangXi province, and provide the experimental and theoretical basis for inorganic-organic hybrids.

开发快速高效止血材料是化学、医药等领域关注的研究热点。项目前期以广西特色资源膨润土为原料，设计合成出“章鱼吸盘”膨润土（BtOS），其在与聚丙烯酸钠（SPA）聚合时将SPA分子链抓住并牢牢吸在膨润土片层上，提高了杂化凝胶的界面结合力，赋予其优异的机械性能及吸水锁水性能，将“吸盘”与Bt间接上“长绳子”合成“章鱼触角”膨润土（BtOT）后，“触角”抑制膨润土再团聚，且与分子链物理缠绕使杂化凝胶性能进一步提高。基于此，本项目拟设计多功能BtOT、壳聚糖、SPA体系，控制合成出多位一体的杂化止血材料，研究其相结构、界面性能等微观结构对材料止血、抗菌等宏观性能的影响规律，探索材料止血的机理。项目的顺利实施，开发出适用于大出血的快速高效止血材料将申请CFDA认证，有望将广西的膨润土产业扩展到一个新的领域，为无机-有机多位一体材料杂化提供实验依据和理论基础。

本项目以广西特色资源膨润土为原料，设计合成出双键型的“章鱼吸盘”膨润土（BtOS），引发双键吸盘使其与丙烯酸钠（SA）原位聚合杂化，将SPA分子链牢牢吸在膨润土片层上，成功合成了类“章鱼触角”结构的杂化止血凝胶，该杂化凝胶的界面结合力得到显著提高，数量众多长的“触角”结构高效抑制膨润土再团聚，且与分子链产生氢键或/和物理缠绕使体系高度杂化形成超网络结构，赋予其优异的机械性能、吸水锁水性能、止血性能。与传统方法制备的复合材料参考组数据相比，其拉伸能量耗散、压缩强度、拉伸强度、韧性、Gʹ的储能模量分别是其14.6、14.1、7.7、4.1、3.6倍；最高吸水率可达1045g/g，体外促凝时间最短为48s，最佳体外凝血指数（BCI）为18，与同等条件下合成出的PAA（吸水率为338g/g，体外促凝时间为113s，BCI为86）相比，其吸水率增加为309%，体外促凝时间为原来的42%，BCI为21%，与纯的粉状的膨润土凝血数据接近, 满足止血材料的要求。并往体系中引入壳聚糖、姜黄素，赋予材料一定的自愈合性及更佳的抗菌性，进一步促进这种高效止血材料的临床应用。探明了相结构、界面性能等微观结构对材料止血、抗菌等宏观性能的影响规律，也初步探索出材料止血的机理。在Polymer, Composites Science and Technology、Industrial & Engineering Chemistry Research、Carbohydrate Polymers、Composites Part A：Applied Science & Manufacturing等期刊发表了7篇与项目相关的研究成果，其中4篇评为当年高被引论文。该杂化凝胶因吸水率高、机械性能好、具有自愈合性、抗菌性，可适用于大出血、关节出血的高效止血场景，为广西的膨润土产业在医用材料领域的应用开辟了新的方向，也为无机-有机多位一体材料杂化提供实验依据与理论基础。