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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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Boundary potentials of bilayer lipid membranes: methods and interpretationsстатья
- Авторы: Ermakov Yu A., Sokolov V.S.
- Сборник: Planar Lipid Bilayers (BLMs) and their applications
- Серия: Membrane Science and Technology Series
- Том: 7
- Глава в коллективной монографии
- Год издания: 2003
- Место издания: Elsevier
- Первая страница: 109
- Последняя страница: 141
- Аннотация: Many physiologically important processes are accompanied by charge transfer across the membrane and adjacent layers, and the related electrostatic phenomena are commonly recognized as a fundamental aspect of membrane biophysics. Both, charge transfer and binding to the surface depend on the electric field distribution at the membrane boundary, which in most cases is determined by the presence of charged lipid species. These circumstances have stimulated extensive use of planar lipid bilayers (BLM) and liposomes as model systems for studies of electrostatic phenomena at the membrane boundaries induced by inorganic ions and substances of biological interest. It is impossible to present here an exhaustive list of publications related to this subject therefore we simply refer the reader to previous reviews and monographs [1, 2]. This paper focuses on principles and applications of a method of measurement of boundary potentials based on the principle of intramembrane field compensation (IFC). The method was developed and used extensively in our studies. When used in combination with other techniques, such as electrophoresis, or ionophore-induced membrane conductance, IFC reveals the 'electrostatic structure' of the membrane in a greater detail than any of these techniques would achieve separately. Below we present observations of electrostatic effects induced by adsorption of inorganic ions or amphiphilic molecules bearing ionized groups or dipole moment and generally characterized by high affinity to phospholipids. We discuss the problem of positioning the bound substances and probes within the membrane and correlation of the adsorption plane with their structure and hydrophobicity. Finally, we discuss IFC application to studies of the distribution of membrane-permeable substances and the possibility of detection of electrically neutral transport of weak acids or bases across the membrane using this technique.
- Добавил в систему: Соколов Валерий Сергеевич