In-silico optimisation of two-dimensional high performance liquid chromatography for the determination of Australian methamphetamine seizure samples.

In-silico optimisation of a two-dimensional high performance liquid chromatography (2D-HPLC) separation protocol has been developed for the interrogation of methamphetamine samples including model, real world seizure, and laboratory synthesised samples. The protocol used Drylab(®) software to rapidly identify the optimum separation conditions from a library of chromatography columns. The optimum separation space was provided by the Phenomonex Kinetex PFP column (first dimension) and an Agilent Poroshell 120 EC-C18 column (second dimension). To facilitate a rapid 2D-HPLC analysis the particle packed C18 column was replaced with a Phenomenex Onyx Monolithic C18 withought sacrificing separation performance. The Drylab(®) optimised and experimental separations matched very closely, highlighting the robust nature of HPLC simulations. The chemical information gained from an intermediate methamphetamine sample was significant and complimented that generated from a pure seizure sample. The influence of the two-dimensional separation on the analytical figures of merit was also investigated. The limits of detection for key analytes in the second dimension determined for methamphetamine (4.59×10(-4)M), pseudoephedrine (4.03×10(-4)M), caffeine (5.16×10(-4)M), aspirin (9.32×10(-4)M), paracetamol (5.93×10(-4)M) and procaine (2.02×10(-3)M).