Computer-assisted method development in liquid chromatography-mass spectrometry: new proposals.

A new approach is proposed for computer-assisted method development in LC-MS. The procedure consists of three stages. Firstly, an accurate retention model is developed for the peaks in the mixture to be separated by use of an iterative approach with isocratic priming data, which is calibrated and validated by means of a few gradient runs. Secondly, a specially developed LC-MS objective function, based on selectivity targets (the selectivity matrix), is calculated and used to evaluate the simulated chromatograms and drive the optimization process. Thirdly, the retention model and the selectivity matrix objective function are used with an evolutionary algorithm in which the concepts of constrained Pareto optimality are applied, to carry out the unattended optimization process. The system was applied to real data for a complex separation and compared with the results provided by a commercial tool for computer-assisted method development.