Optimizing the performance of tin dioxide microspheres for phosphopeptide enrichment Original Research Article

Phosphopeptide enrichment based on metal oxide affinity chromatography is one of the most powerful tools for studying protein phosphorylation on a large scale. To complement existing metal oxide sorbents, we have recently introduced tin dioxide as a promising alternative. The preparation of SnO2 microspheres by the nanocasting technique, using silica of different morphology as a template, offers a strategy to prepare materials that vary in their particle size and their porosity. Here, we demonstrate how such stannia materials can be successfully generated and their properties fine-tuned in order to obtain an optimized phosphopeptide enrichment material. We combined data from liquid chromatography–mass spectrometry experiments and physicochemical characterization, including nitrogen physisorption and energy-dispersive X-ray spectroscopy (EDX), to explain the influence of the various experimental parameters.