In metabolomics studies, large sample sets have to be analyzed to allow statistical differentiation of sample types. Obviously, repeatability of the whole analytical workflow, including sample preparation, sample introduction, separation and detection, is extremely important in order to achieve such a differentiation. Automating the sample preparation workflow is a very useful first step towards reducing analytical variability.

In a series of articles, we will describe the use of the GERSTEL MPS WorkStation for automated sample preparation applied to metabolomics studies. In this first part, we highlight an automated sample preparation method, which was developed for the extraction of glycosides from plant material using the GERSTEL MPS Dual Head WorkStation. Ultrasonic assisted solvent extraction was performed on the plant material, and the extract was prepared for subsequent LC-MS analysis by two fully automated consecutive filtration steps, combining a first filtration on a 17 μm stainless steel screen filter placed in the sample vial and an additional filtration step using a 0.45 μm syringe filter. The obtained extracts were analyzed by LC-MS with excellent reproducibility.