Blind column selection protocol for two-dimensional high performance liquid chromatography

The selection of two orthogonal columns for two-dimensional high performance liquid chromatography (LC x LC) separation of natural product extracts can be a labour intensive and time consuming process and in many cases is an entirely trial-and-error approach. This paper introduces a blind optimisation method for column selection of a black box of constituent components. A data processing pipeline, created in the open source application OpenMS (R), was developed to map the components within the mixture of equal mass across a library of HPLC columns; LC x LC separation space utilisation was compared by measuring the fractional surface coverage, f(coverage). It was found that for a test mixture from an opium poppy (Papaver somniferum) extract, the combination of diphenyl and C18 stationary phases provided a predicted f(coverage) of 0.48 and was matched with an actual usage of 0.43. OpenMS (R), in conjunction with algorithms designed in house, have allowed for a significantly quicker selection of two orthogonal columns, which have been optimised for a LC x LC separation of crude extractions of plant material. (c) 2016 Elsevier B.V. All rights reserved.