Use either 0.1 N HCl or 0.1 N NaOH for dissolving tyrosine to prepare standard curve. Prepare the stock solution is either of these two solutions and then you can make dilutions in water for your standard curve. Good luck.

What kind of methods do you use to quantify Tyrosine? Fluorescence? UV absorbance at 280 nm? or others?

And what kind of the solution is used to dissolve the sample in?

Organic solvents, such as alcohol, acetone, DMSO, will dissolve tyrosine well. But they might not be used for your assay methods.

First take samll amount of ethanol and dissolve the Tyrosine then add DM water as per your requirement.

Water Solubility

479 mg/L (at 25 °C)

SEIDELL,A (1941)

Thank you guys