Microscopic potential. It represents the smallest electrokinetic potential difference that can be detected between the surface of a biological object and the solution in which it is immersed. This value is denoted by the symbol Δμ (Δμ' for salt solutions), i.e. ∆μ=Δμ'. The potential of microscopic electrochemical equilibrium depends only on the concentration of charged particles on both sides of the cell membrane (See Potency). In this case, the total charge in the solution is zero, and the system comes to equilibrium in the same way as it happens in dilute solutions of electrolytes.
Using microelectrodes, the values of both membrane and microscopic potentials are determined. The membrane or critical potential refers to the maximum potential that is achieved when the microelectrode approaches the membrane, and the polarization jump that occurs in this case characterizes the permeability of the membrane. The Ioffe field setup for studying the action of potentials on a cell allows one to observe the cell from all sides, rotating it around any