General Treatment of pH-Solubility Profiles of Weak Acids and Bases and the Effects of Different Acids on the Solubility of a Weak Base

Carvedilol: Solubilization and Cyclodextrin Complexation: A Technical Note

“…Addition of phosphoric acid had less effect on the solubility than hydrochloric acid. It is known that different pH-adjusting acids can have significant effect on the aqueous solubility of weak base and that the solubility product of the protonated base and the anionic form of the acid can result in significant solubility deviations (22)(23)(24). This could explain why we were observing lower solubility when the pH was adjusted with hydrochloric acid.…”

The Utility of Sulfonate Salts in Drug Development

“…Streng et al 40 reported on the relative solubilities of the lactate, phosphate, hydrochloride, and mesylate salts of terfenadine. They reported significant solubility differences ranging from 0.5 to 5.0 mg/mL.…”

Salt Solubility Products of Diprenorphine Hydrochloride, Codeine and Lidocaine Hydrochlorides and Phosphates – Novel Method of Data Analysis Not Dependent on Explicit Solubility Equations

“…The "anomalies" in the shapes of logS -pH profiles that cannot accurately be predicted by the Henderson-Hasselbalch may be common with sparingly-soluble or practically-insoluble drugs, such as diprenorphine, but are not always easy to recognize unless accurately-determined pK a values are available [28]. Phosphate buffers can dramatically influence the solubility profiles of ionizable drugs, as shown here and elsewhere [16,29]. These and other similar complications may be common, but are not always easy to interpret quantitatively.…”