Challenge from the simple: some caveats in linearization of the Boyle-van't Hoff and Arrhenius plots.
Some aspects of proper linearization of the Boyle-van't Hoff (BVH) relationship for calculation of the osmotically inactive volume v(b), and Arrhenius plot (AP) for the activation energy E(a) are discussed. It is shown that the commonly used determination of the slope and the intercept (v(b)), which are presumed to be independent from each other, is invalid if the initial intracellular molality m(0) is known. Instead, the linear regression with only one independent parameter (v(b)) or the Least Square Method (LSM) with v(b) as the only fitting LSM parameter must be applied. The slope can then be calculated from the BVH relationship as the function of v(b). In case of unknown m(0) (for example, if cells are preloaded with trehalose, or electroporation caused ion leakage, etc.), it is considered as the second independent statistical parameter to be found. In this (and only) scenario, all three methods give the same results for v(b) and m(0). AP can be linearized only for water hydraulic conductivity (L(p)) and solute mobility (omega(s)) while water and solute permeabilities P(w) identical withL(p)RT and P(s) identical withomega(s)RT cannot be linearized because they have pre-exponential factor (RT) that depends on the temperature T.
Katkov
Igor I
II
CELLTRONIX, San Diego, California, USA. prodvincell@hotmail.com
D001834:Body Water / Q000378:metabolism; D002463:Cell Membrane Permeability / Q000502:physiology; D048429:Cell Size; D008954:Models, Biological; D009994:Osmolar Concentration; D012996:Solutions / Q000378:metabolism; D013816:Thermodynamics
D012996:Solutions