A simple approach for reversed phase column comparisons via the Tanaka test

The Tanaka test is a classical characterization scheme designed in 1989 for highlighting the main reversed phase attributes of C18 columns: hydrophobicity, shape/steric selectivity, hydrogen bonding, ion exchange (pH < 7 and pH > 7 environments). In this short communication, we present it in a simplified manner that requires basic HPLC and spreadsheet operations; encouraging analysts of all levels of expertise to begin capturing an in-house library of column comparison knowledge based on their laboratory's unique set of phases and previously developed separations. This approach does not compete, nor replace existing techniques such as quantitative structure-retention relationship (QSSR) models to aid column selection. It is simply an alternative or additional aid to support column selection decisions that is easily accessible and implementable.