Retention of Ionizable Compounds on HPLC. pH Scale in Methanol−Water and the pK and pH Values of Buffers

摘要: Several properties of methanol−water mixtures (molar volume, molar refractivity, Debye−Huckel parameters, pH scale, HPLC-useful range, dissociation constants acids) are studied. Some macroscopic used to calculate the extent interaction. Solute properties, such as pKa values, depend on preferential solvation solute by three solvents that coexist in mixture (methanol, water, aggregrates). Based this and interaction, equations relate values acids with solvent composition derived. The applied several widely prepare HPLC buffers. an acid a buffered solution at any can be easily calculated from proposed equations. chromatographic retention thus related real value mobile phase used. This procedure is more rigorous should give better re...