Laboratory of Chemical Physics, Bldg. 5, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
Phys Chem Chem Phys. 2011 Sep 14;13(34):15403-17. doi: 10.1039/c1cp21086f. Epub 2011 Jul 21.
Water molecules confined to pores with sub-nanometre diameters form single-file hydrogen-bonded chains. In such nanoscale confinement, water has unusual physical properties that are exploited in biology and hold promise for a wide range of biomimetic and nanotechnological applications. The latter can be realized by carbon and boron nitride nanotubes which confine water in a relatively non-specific way and lend themselves to the study of intrinsic properties of single-file water. As a consequence of strong water-water hydrogen bonds, many characteristics of single-file water are conserved in biological and synthetic pores despite differences in their atomistic structures. Charge transport and orientational order in water chains depend sensitively on and are mainly determined by electrostatic effects. Thus, mimicking functions of biological pores with apolar pores and corresponding external fields gives insight into the structure-function relation of biological pores and allows the development of technical applications beyond the molecular devices found in living systems. In this Perspective, we revisit results for single-file water in apolar pores, and examine the similarities and the differences between these simple systems and water in more complex pores.
水分子被限制在亚纳米直径的孔隙中，形成单链氢键。在这种纳米尺度的限制下，水具有不寻常的物理性质，这些性质在生物学中得到了利用，并为广泛的仿生学和纳米技术应用带来了希望。后者可以通过碳和氮化硼纳米管来实现，这些纳米管以相对非特异性的方式限制水，并适合研究单链水的固有性质。由于强的水分子氢键，尽管它们的原子结构不同，单链水中的许多特性在生物和合成孔隙中都得到了保留。水链中的电荷输运和取向有序性对静电效应非常敏感，并主要由其决定。因此，用非极性孔隙和相应的外部场来模拟生物孔隙的功能，可以深入了解生物孔隙的结构-功能关系，并允许开发超越生命系统中发现的分子器件的技术应用。在本观点中，我们重新审视了非极性孔隙中单链水的结果，并比较了这些简单系统与更复杂孔隙中水中的相似性和差异性。
