Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan.
Department of Bioengineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan.
J Phys Chem Lett. 2020 Jul 16;11(14):5756-5762. doi: 10.1021/acs.jpclett.0c01084. Epub 2020 Jul 7.
Water inside and between cells with dimensions on the order of 10-10 nm such as synaptic clefts and mitochondria is thought to be important to biological functions, such as signal transmissions and energy production. However, the characterization of water in such spaces has been difficult owing to the small size and complexity of cellular environments. To this end, we proposed and fabricated a biomimetic nanospace exploiting nanofluidic channels with defined dimensions of hundreds of nanometers and controlled environments. A method of modifying a glass nanochannel with a unilamellar lipid bilayer was developed. We revealed that 2.1-5.6 times higher viscosity of water arises in a 200 nm sized biomimetic nanospace by interactions between water molecules and the lipid bilayer surface and significantly affects the molecular/ion transport that is required for the biological functions. The proposed method provides both a technical breakthrough and new findings to the fields of physical chemistry and biology.
细胞内和细胞间具有 10-10nm 量级尺寸的水，如突触间隙和线粒体，被认为对生物功能很重要，如信号传递和能量产生。然而，由于细胞环境的体积小且复杂，对这些空间中的水的特性进行描述一直具有挑战性。为此，我们提出并制造了一种仿生纳米空间，利用具有数百纳米尺寸的纳米流道和可控环境。开发了一种用单层脂质双层修饰玻璃纳米通道的方法。我们揭示了在 200nm 尺寸的仿生纳米空间中，水分子与脂质双层表面之间的相互作用会导致水的粘度增加 2.1-5.6 倍，这会显著影响生物功能所需的分子/离子传输。所提出的方法为物理化学和生物学领域提供了技术突破和新发现。
