Influence of Dielectric constant on Protonation Equilibria of L-Cysteine and L-Methionine in 1, 4-Dioxane-Water Mixture
نویسنده
چکیده
The solute-solvent interactions of L-Cysteine and L-Methionine have been studied pH metrically in various concentrations (0.060.0% v/v) 1, 4-Dioxane-water mixture maintaining an ionic strength of 0.16 mol L-1 at ambient conditions. The protonation constants have been calculated with the computer program MINIQUAD75 and the best fit chemical models are selected based on statistical parameters. Linear variation of step-wise protonation constants (log K) with reciprocal of dielectric constant of the solvent mixture has been attributed to the dominance of the electrostatic forces. Protonation equilibria and effect of influential parameters on the protonation constants have also been presented. KeywordsProtonation equilibria, L-Cysteine, L-Methionine, 1, 4-Dioxane
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