The effects of various solvents and pH on the solubility cbaracteristics of glycine, L-alanine, L-valine, L-phenylalanine, and DL-amino octanoic acid were studied in a series of hydroalcoholic solvent systems. The solubility properties of the amino acids studied were found to be dominated by the a-amino carboxylic acid portion of the molecule but also depended to some extent on the nonpolar portion of the molecule and its interaction with each specific solvent system. These interactions gave rise to a rank order of solubility which was characteristic of the specific amino acid rather than the decreasing polarity of the solvent system. Similar solubility profiles were found throughout the concentration spectrum and were defined by using a polynomial regression analysis. As the percent of alcohol was increased in the solvent systems studied, similar increments of acid or base added to the system produced a proportionally greater increase in the magnitude of total amino acid solubility.
Keyphrases 0 Amino acid solubility-hydroalcoholic solvent systems 0 Hydroalcoholic solvent systems-amino acid solubility 0 a-Amino carboxylic acid group domination-amino acid solubility 0 Dielectric constant effect-amino acid solubility