I am attempting to solubilize uracil for use in yeast growth media. I am encountering conflicting reports as to the best way to solubilize uracil (from Sigma-Aldrich) to make a stock solution. Also, none of these reports allow for a concentration that is suitable for yeast growth media (URA- yeast). Does anyone have a "tried and true" method that they use? What solvent do you use and what is the maximum concentration you can achieve?
I prepare uracil stocks at 2 mg/mL in water, stored at -20*C. It does take a while to dissolve (uracil is not exactly hydrophilic) and you can't prepare it at higher concentrations. I use it at a final concentration of 20 ug/mL for URA- Saccharomyces strains.
I prepared uracil stock at 1.0 g / 100 mL in water by adding a drop of 1N NaOH,