Advances in solvent-free sample preparation methods for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) of polymers and biomolecules

Matrix assisted laser desorption ionization mass spectrometry (MALDI-MS) is an essential analytical technique for the molecular characterization of biomolecules and synthetic polymers. Its ability to provide comprehensive compositional information not afforded by other techniques, with high sensitivity and selectivity, is highly influenced by the sample preparation of the material prior to analysis. This review discusses MALDI-MS sample preparation protocols that do not utilize solvents. Such methods provide alternative routes for analyzing insoluble polymeric materials and may also reveal information that is not attainable with solvent-based sample preparation techniques. Additionally, this review will present relevant surface analysis and imaging results only achievable with solvent-free sample preparation methodologies.