EAPSI: New insights into the effects of chemical composition and surface structure on spider silk adhesion and prey retention

附着力是施工和维修中的重要考虑因素。生物进化出不同的粘合剂，以便在地球上几乎每一种环境中生存。在化学粘附中，化学键的形成和电子的共享在表面之间产生吸引力。例如，蜘蛛利用一种粘性的聚合物胶水将猎物困在它们的网中。这个项目将测试如何粘合强度的骨料胶水变化的基础上表面粗糙度，亲水性和化学成分。与东京大学的Tadashi Miyashita博士合作-之前唯一研究过蜘蛛Cytarachne的丝的研究人员-该研究将确定哪些表面特征作为进化压力，导致最佳的胶水粘合力。将对胶滴的化学成分进行鉴定。通过对蜘蛛的研究，可以利用和模仿聚集体胶的化学成分，从而生产出基质特异性的合成粘合剂产品。聚集体丝由糖蛋白核心和盐的水性液滴组成。盐和糖蛋白的结合共同作用，在丝线和猎物之间形成了一个键。蜘蛛属Cyrtarachne是专门的蛾狩猎球织，只有在亚洲和日本更常见。这些蜘蛛已经进化到通过利用带有异常大的粘性胶滴的缩小的圆网来捕食飞蛾。成功捕获猎物主要依赖于胶水和外骨骼之间的长期粘附。不同的表面结构和化学成分可能会与糖蛋白和吸湿盐发生不同的反应，从而导致Cyrtarachne聚集胶低于或超过性能的情况。将通过拉脱法进行粘附试验。将获得关于它们含有什么化学物质以及它们何时最强的信息。这个NSF EAPSI奖是与日本科学促进协会合作资助的。

Adhesion is an important consideration in construction and repair. Organisms have evolved different adhesives for survival in nearly every environment on earth. In chemical adhesion the formation of chemical bonds and sharing of electrons create attractive forces between surfaces. For example, spiders utilize a sticky aggregate glue to keep their prey ensnared in their webs. This project will test how adhesion strength of aggregate glue varies based on surface roughness, hydrophilicity, and chemical composition. In collaboration with Dr. Tadashi Miyashita at the Unversity of Tokyo - the only researcher to have previously studied the silk of the spider Cytarachne - the research will be determined which surface characteristics have served as evolutionary pressures, leading to optimal glue adhesion. Identification of the chemical composition of glue droplets will be conducted. By studying spiders, it can lead to the utilization and mimicking of aggregate glue chemical compounds leading to substrate specific synthetic adhesive products.Aggregate silk is composed of a glycoprotein core and an aqueous droplet of salts. The combination of salts and the glycoproteins act together to form a bond between the silk threads and prey. Spiders from the genus Cyrtarachne are specialized moth-hunting orb-weavers, only found within Asia and more commonly in Japan. These spiders have evolved to prey on moths by utilizing reduced orb webs with unusually large, viscous droplets of glue. Successful prey capture relies primarily on the prolonged adhesion between the glue and exoskeleton. Varying surface structures and chemical compositions may react with glycoproteins and hydroscopic salts differently resulting in scenarios in which Cyrtarachne aggregate glue under or over performs. Adhesion tests will be conducted by the pull-off method. Information will be gained on what chemicals they contain, and when they are strongest. This NSF EAPSI award is funded in collaboration with the Japan Society for the Promotion of Science.