Biomimetic underwater adhesives with environmentally triggered setting mechanisms.
Biomimetic underwater adhesives with environmentally triggered setting mechanisms.
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DOI：
10.1002/adma.200902380
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发表时间：
2010-02-09
影响因子：
29.4
通讯作者：
Stewart, Russell J.
中科院分区：
文献类型：
--
作者：
Shao, Hui;Stewart, Russell J.
开发用于开放手术潮湿环境的医用粘合剂的挑战类似于生活在陆地和海洋的水界面的海洋生物所解决的粘合问题。这些生物通常在海水中将不同的材料粘合在一起，几乎没有任何表面处理。一种这样的生物是沙堡蠕虫（Phragmatopoma californica）。我们的目标是复制这种海洋蠕虫的水下粘合机制，以创建合成的水性水下医疗粘合剂，反过来，使用合成粘合剂来测试有关天然粘合剂的机械假说。仿生水下胶粘剂配制与聚电解质类似物的天然胶蛋白。共聚物凝聚成复杂的凝聚层-致密的部分水不混溶的粘性流体之间的可溶性聚合物和不溶性聚合物盐。流体凝聚相和固体或凝胶状态之间的边界取决于二价阳离子种类以及pH和温度，这表明这些环境因素可以触发粘合剂固化反应（图1）。研究结果分别为天然pH值触发集假说和模拟医用粘合剂的控制集的实际触发提供了经验支持。沙堡蠕虫生活在保护性管状壳中，它通过将沙子和贝壳碎用蛋白质粘合剂粘合在一起而在水下组装。[1-3]为了建造水下沙堡，沙虫必须解决三个主要问题：第一，它的粘合剂必须与潮湿表面形成强有力的化学键，这样做它必须取代界面水;[4，5]第二，它的水性液体粘合剂在水下分泌时不能溶解到海洋中;第三，粘合剂的凝固必须精确定时。如果凝固太快，胶水就会堵塞蠕虫的粘合剂管道，这是一个明显的问题，而凝固太慢则效率低下。沙堡胶是由带相反电荷的蛋白质，加上钙和镁离子。高比例的带电侧链（磷酸盐和胺）和具有儿茶酚侧链的二羟基苯丙氨酸（多巴）残基帮助粘合剂突破界面水屏障以解决第一个问题。多巴残留物被认为是对湿金属氧化物表面的强粘附的促进剂。[2，6，7]为了解决第二个问题，带相反电荷的蛋白质可以静电结合成致密的粘性流体-复合凝聚层[8，9]-其在水中部分不混溶，但在浸没的表面上扩散并润湿。[3]胶蛋白类似物合成为水溶性丙烯酸酯，含有磷酸盐、胺和儿茶酚侧链，当在正确的条件下混合时，其比例与天然粘附蛋白相似，从而凝聚成复合凝聚层。[10]第三个问题是硬化反应的时间，这可能与分泌颗粒（pH = 5）和海水（pH = 8.2）之间的pH差异有关。[3，11]分泌到海水中
The challenges of developing medical adhesives for the wet environment of open surgery are analogous to the adhesion problems solved by marine organisms living at the watery interface of land and ocean. These organisms routinely bond dissimilar materials together under seawater with little if any surface preparation. One such organism is the sandcastle worm (Phragmatopoma californica). Our goal is to copy this marine worm’s mechanisms of underwater bonding to create synthetic water-borne underwater medical adhesives, and in turn, to use the synthetic adhesives to test mechanistic hypotheses about the natural adhesive. Biomimetic underwater adhesives were formulated with polyelectrolytic analogues of the natural glue proteins. The copolymers condensed into complex coacervates—dense partially water-immiscible cohesive fluids poised between soluble polymers and insoluble polymeric salts. The boundary between fluid coacervate phases and solid or gelled states was dependent on divalent cation species as well as the pH and temperature, which demonstrated that these environmental factors can trigger the adhesive setting reaction (Fig. 1). The results provide, respectively, empirical support for the natural pH-triggered set hypothesis and practical triggers for controlled setting of mimetic medical adhesives.The sandcastle worm lives in protective tubular shells, which it assembles underwater by gluing together sand and seashell hash with a proteinaceous adhesive.[1-3] To build underwater sandcastles, the worm had to solve three major problems: first, its adhesive must form strong chemical bonds with wet surfaces and to do so it must displace interfacial water;[4, 5] second, its water-borne fluid adhesive must not dissolve into the ocean when it is secreted underwater; and third, setting of the adhesive must be accurately timed. If it sets too fast, the glue would plug up the worm’s adhesive ducts, an obvious problem, while setting too slowly would be inefficient. The sandcastle glue is composed of oppositely charged proteins, plus calcium and magnesium ions. A high proportion of charged sidechains (phosphates and amines) and dihydroxyphenyl-alanine (dopa) residues with catechol sidechains help the adhesive breech the interfacial water barrier to solve the first problem. Dopa residues have been implicated as promoters of strong adhesion to wet metal oxide surfaces.[2, 6, 7] To solve the second problem, the oppositely charged proteins may associate electrostatically into a dense cohesive fluid—a complex coacervate [8, 9]—that is partially immiscible in water, yet spreads over and wets submerged surfaces.[3] Glue protein analogues synthesized as water-soluble acrylates containing phosphate, amine, and catechol sidechains in similar proportions as the natural adhesive proteins condensed into complex coacervates when mixed under the right conditions.[10] Timing the hardening reaction, the third problem, is likely coupled to the pH differential between secretory granules (pH≈ 5) and seawater (pH= 8.2).[3, 11] Secretion into seawater
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影响因子：
2.8
作者：
Sun, ChengJun;Fantner, Georg E.;Waite, J. Herbert
通讯作者：
Waite, J. Herbert
影响因子：
4.6
作者：
Shao, Hui;Bachus, Kent N.;Stewart, Russell J.
通讯作者：
Stewart, Russell J.
影响因子：
3.9
作者：
Stevens, Mark J.;Steren, Rebekah E.;Stewart, Russell J.
通讯作者：
Stewart, Russell J.
DOI：
10.1007/bf00695330
发表时间：
1988-01-01
影响因子：
2
作者：
JENSEN, RA;MORSE, DE
通讯作者：
MORSE, DE
影响因子：
4.6
作者：
Gil, ES;Spontak, RJ;Hudson, SM
通讯作者：
Hudson, SM