Use of optimization software to determine rugged analysis conditions in high-performance liquid chromatography

The ruggedness evaluation of an analytical method is now generally required for further validation. By considering ruggedness at an early stage of method development, major disappointments and amount of work could be avoided. This work shows that the optimization software OSIRIS can be helpful for the chromatographer during a method development, as it takes into account the method ruggedness. The ruggedness of the analysis conditions is then evaluated all along the selectivity optimization procedure. This optimization software belongs to the interpretive methods that consist of predicting the optimum conditions by modeling first the solute retention over the parameter space using a minimum number of preliminary runs. The choice of a response function is studied. This response function must be able to take into account several individual criteria: analysis time, minimal resolution and ruggedness of each parameter. Some optimum separations, determined using a ruggedness criteria or not, are given and compared in terms of long term repeatability.