What’s New in Reversed-Phase Liquid Chromatography Selectivity? An Update from the Perspective of the Hydrophobic Subtraction Model

It has been more than five years since the last update in this column on the evolution of the Hydrophobic Subtraction Model (HSM) of reversed-phase selectivity and characteristics of new stationary phases recently characterized using the model. In this time, nearly 50 new columns have been added to the public HSM database, and new perspectives on the limitations and use of the model have been published. In this installment, I discuss the continuing evolution of the model, and characteristics of the recently added columns, with an eye toward use of this information for troubleshooting and method development.