Surfaces and interfacial water: Evidence that hydrophilic surfaces have long-range impact
Surfaces and interfacial water: Evidence that hydrophilic surfaces have long-range impact
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DOI：
10.1016/j.cis.2006.07.002
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发表时间：
2006-11-23
影响因子：
15.6
通讯作者：
Pollack, Gerald H.
中科院分区：
文献类型：
--
作者：
Zheng, Jian-ming;Chin, Wei-Chun;Pollack, Gerald H.
通常认为，表面对连续水相的影响延伸到不超过几个水分子层的距离。另一方面，较早的研究表明，影响更为广泛。我们在这里报告，胶体和分子溶质悬浮在水溶液中的深刻和广泛的各种亲水表面附近排除。无溶质区的宽度通常为数百微米。在许多类型的表面附近观察到这种大的排除区，包括人工和天然水凝胶、生物组织、亲水性聚合物、单层和离子交换珠以及各种溶质。使用显微镜观察，以及电位和紫外-可见吸收光谱，红外成像，和NMR成像的测量，我们发现，溶质的自由区是一个物理上不同的和较少的移动的水相，可以无限期地共存与连续的含溶质相。这种修饰区的广泛性令人印象深刻，并且在许多领域中对表面-分子相互作用具有广泛的意义，包括细胞识别，生物材料-表面修饰，生物分离技术以及生物学，物理学和化学的其他领域。(c)2006年由Elsevier B.V出版
It is generally thought that the impact of surfaces on the contiguous aqueous phase extends to a distance of no more than a few water-molecule layers. Older studies, on the other hand, suggest a more extensive impact. We report here that colloidal and molecular solutes suspended in aqueous solution are profoundly and extensively excluded from the vicinity of various hydrophilic surfaces. The width of the solute-free zone is typically several hundred microns. Such large exclusion zones were observed in the vicinity of many types of surface including artificial and natural hydrogels, biological tissues, hydrophilic polymers, monolayers, and ion-exchange beads, as well as with a variety of solutes. Using microscopic observations, as well as measurements of electrical potential and UV-Vis absorption-spectra, infrared imaging, and NMR imaging, we find that the solute-free zone is a physically distinct and less mobile phase of water that can co-exist indefinitely with the contiguous solute-containing phase. The extensiveness of this modified zone is impressive, and carries broad implication for surface-molecule interactions in many realms, including cellular recognition, biomaterial-surface antifouling, bioseparation technologies, and other areas of biology, physics and chemistry. (c) 2006 Published by Elsevier B.V