Chromatography Forum

Hi,
Does anyone know of a quick way of dissolving amino acids in water as I having difficulty with some of them, particularly cystine and aspartic acid.
I know I will probably have to adjust them with acid/base but I was wondering if someone had a quick solution that they applied before.
It's just that I'm under pressure for time....
Any help would be grateful.
Thanks

Heat, sonicate, or both, use more H2O.

Cystine just has poor solubility, and so does tyrosine, but they are more soluble in base than acid. As a general rule amino acids are less soluble near their isoelectric points. For most amino acids, I usually use 0.1 M HCl to make the stock solutions around 20 mM then dilute that to a working concentration in something more agreeable with the chromatography. For the few that have solubility problems, I just make the stocks less concentrated and use more in the dilution.