Laboratory for Fundamental BioPhotonics (LBP), Institute of Bioengineering (IBI), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Institute of Materials Science and Engineering (IMX), School of Engineering (STI), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland.
Nano Lett. 2022 Sep 28;22(18):7394-7400. doi: 10.1021/acs.nanolett.2c02206. Epub 2022 Sep 6.
Water is the liquid of life thanks to its three-dimensional adaptive hydrogen (H)-bond network. Confinement of this network may lead to dramatic structural changes influencing chemical and physical transformations. Although confinement effects occur on a <1 nm length scale, the upper length scale limit is unknown. Here, we investigate 3D-confinement over lengths scales ranging from 58-140 nm. By confining water in zwitterionic liposomes of different sizes and measuring the change in H-bond network conformation using second harmonic scattering (SHS), we determined long-range confinement effects in light and heavy water. DO displays no detectable 3D-confinement effects <58 nm (<3 × 10 DO molecules). HO is distinctly different. The vesicle enclosed inner H-bond network has a different conformation compared to the outside network and the SHS response scales with the volume of the confining space. HO displays confinement effects over distances >100 nm (>2 × 10 HO molecules).
水是生命的液体，这要归功于其三维自适应氢键（H）网络。这种网络的限制可能会导致剧烈的结构变化，影响化学和物理转化。尽管限制效应发生在小于 1nm 的长度尺度上，但长度尺度的上限是未知的。在这里，我们研究了 3D 限制在 58-140nm 的长度尺度范围内的情况。通过在不同大小的两性离子脂质体中限制水，并使用二次谐波散射（SHS）测量氢键网络构象的变化，我们在轻水和重水中确定了长程限制效应。DO 在 <58nm(<3×10 DO 分子)时没有检测到 3D 限制效应。HO 则明显不同。与外部网络相比，囊泡封闭的内部氢键网络具有不同的构象，并且 SHS 响应与限制空间的体积成正比。HO 在 >100nm(>2×10 HO 分子)的距离上显示出限制效应。
