Stevens Mark J, Steren Rebekah E, Hlady Vladimir, Stewart Russell J
Department of Bioengineering, University of Utah, Salt Lake City, Utah 84112, USA.
Langmuir. 2007 Apr 24;23(9):5045-9. doi: 10.1021/la063765e. Epub 2007 Mar 30.
Phragmatopoma Californica builds a tubular dwelling by gluing bits of sand and seashell together underwater with a proteinaceous adhesive. In the lab, the animals will build with 0.5 mm glass beads. Two spots of glue with a consistent volume of about 100 pL each are deposited on the glass beads before placement on the end of the tube. The animals wriggled the particles for 20-30 s before letting go, which suggested that the adhesive was sufficiently set within 30 s to support the glass beads. The structure of the adhesive joints was examined at the micro- and nanoscopic length scales using laser scanning confocal and atomic force microscopies. At the microscale, the adhesive was a cellular solid with cell diameters ranging from 0.5 to 6.0 mum, distributed to create a steep porosity gradient that ranged from near zero at the outside edges to about 50% at the center of the adhesive joint. At the nanoscale, the adhesive appeared to be an accretion of trillions of deformable nanospheres, reminiscent of a high-solids-content latex adhesive. The implications of the structure for the functionality of the adhesive is discussed.
加州盘管虫通过用一种蛋白质类粘合剂将沙粒和贝壳碎片在水下粘在一起，构建出一个管状栖息地。在实验室中，这些动物会用0.5毫米的玻璃珠来构建。在将玻璃珠放置在管端之前，在玻璃珠上沉积两个体积约为100皮升的胶水点。这些动物在放开玻璃珠之前会扭动它们20 - 30秒，这表明粘合剂在30秒内充分固化以支撑玻璃珠。使用激光扫描共聚焦显微镜和原子力显微镜在微观和纳米尺度上检查粘合剂接头的结构。在微观尺度上，粘合剂是一种细胞固体，细胞直径在0.5到6.0微米之间，分布形成一个陡峭的孔隙率梯度，从粘合剂接头外边缘的接近零到中心的约50%。在纳米尺度上，粘合剂似乎是数万亿个可变形纳米球的堆积，让人联想到高固含量的乳胶粘合剂。文中讨论了该结构对粘合剂功能的影响。
