A new approach to study benzodiazepine separation and the differences between a methanol/water and acetonitrile/water mixture on column efficiency in liquid chromatography

A chemometric methodology was used to study column efficiency and the separation of 10 benzodiazepines in reversed phase liquid chromatography. New simple mathematical models and the organic modifier (OM) organization of ACN in the water, explained differences on column efficiency observed when ACN is chosen instead of CH3OH. A new response function, which takes into account the separation quality and the analysis time, was proposed for the separation optimization. The result, a mobile phase ACN/water (60/40)(V/V), with a flow rate = 1.00 mL/min and a column temperature = 47 degrees C were optimum values for a rapid chromatographic separation.