Today’s chromatographers face the same challenges that chromatographers faced 25 years ago—to develop methods that maximize resolution between their analytes of interest. Selection of an appropriate pH for the analytes of interest is critical for ionizable compounds. Once the stationary phase, organic solvent, and pH are selected, vary temperature and gradient time. Then use of a commercially available method optimization software package is recommended. While C18 is a good all-purpose phase for initial method development, the other phases offer alternate selectivities. It is good practice to screen multiple phases to ensure the best possible separation.
