Membrane potentials physical origins

The origin of the frequency dependent membrane capacitance is not well understood, although it is likely to be due to membrane proteins. However, there are a variety of proteinous components in the membrane and most of them are not directly related to ionic channels. Therefore, it is virtually impossible to physically separate the capacitance due to gating proteins from capacitances due to other proteins. However, if the frequency dependent capacitance is related to gate proteins, the capacitance must change with an increase or decrease in the membrane potential. It is known that ionic channels are not tightly closed at the resting state (membrane potential near -60 mV). 

Various methods are available for monitoring electric potential generation in illuminated photosynthetic membranes. These include the use of electrodes, free-flow electrophoresis, distribution or binding of amphiphilic dyes and optical changes of intrinsic or added field-sensitive probes. Some of these events seem to be correlated kinetically but without certainty about their precise mechanism and origin they remain difficult to accomodate in a single physical model. As part of such correlation studies we have determined the temperature dependence of some of these electric events that are thought to reflect thylakoid membrane potentials or interfacial electric potentials. 

Surface potentials at the electrode-solution interface have been described by a number of formalisms. The most successful of these originates from Gouy and Chapman whom suggested that Poisson-Boltzmann approaches best describes the state of affairs at the electrode surface in contact with an aqueous solution (further elaborations are outlined by Bockris Reddy). Within Electrochemistry this proved very successful and analogous formalisms were subsequently applied to physical descriptions of biological surfaces. The resultant Poisson-Boltzmann equation with defined boundary conditions can be solved analytically to yield an expression for the membrane surface potential as follows ... 

Thermotropic liquid crystals hold a dominant position in the field of the LCD however, researchers have also to pay attention to another type of liquid crystals, lyotropic liquid crystals, fi om the aspect of the life science field. Essential properties of cell membranes originate from their liquid crystalline behavior. The point of view of biophysics exists in the liquid crystal discovery time inferred from the monograph of Otto Lehmaim titled The liquid crystal and life flieory . In the experimental research of material science, the development of science cannot be expected without collaboration with a physicist, a physical chemist, and a synthetic chemist, as showing the history of research not only as that of liquid crystals but also of macromolecules and colloid science, among others. Because a considerable portion of a living organism (cell membrane, skin structure, etc.) is composed of liquid crystalline states, participation of researchers from many different fields is necessary for the bio-matter liquid crystal. I would hope to see the development of medical science, pharmacy, and foods by the full utilization of the potential of liquid crystal materials. 

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