Water activity and osmotic coefficients in solutions of glycine, glutamic acid, histidine and their salts at 298.15 K and 310.15 K

摘要

From vapor pressure osmometry data, the activity of water, osmotic coefficients and mean ionic activity coefficients of glycine (m = 0.006-3.2 mol center dot kg(-1)), L-histidine (in = 0.005-0.23 mol center dot kg(-1)), L-histidine monohydrochloride (m = 0.008-0.63 mol center dot kg(-1)), glutamic acid (m = 0.004-0.05 mol center dot kg(-1)), sodium L-glutamate (m = 0.007-0.6 mol center dot kg(-1)), and calcium L-glutamate (m = 0.008-0.6 mol center dot kg(-1)) have been obtained in aqueous solutions at 298.15 and 310.15 K. The Pitzer equations and the mean spherical approximation (MSA) are used for theoretical modeling. The results are supplied as reference thermodynamic material for the characterization of more complex molecules such as proteins.