Mass spectrometry imaging: the future is now

Since its introduction, mass spectrometry (MS) imaging (MSI or IMS) has revolutionized all areas of the scientific domain that have found applications for this rapidly developing analytical method. MSI combines the specificity of MS with the spatial power of histology to create chemical images of analytes of interest in complex biological tissue sections. Currently, the most popular MSI methods are matrix-assisted laser desorption ionization (MALDI) and the ambient desorption electrospray ionization (DESI), both of which have their own advantages and disadvantages, with secondary ion mass spectrometry (SIMS) gaining popularity for selected applications. MALDI-MSI has by far been the most successful imaging modality with applications within multiple areas of bioanalysis including drug distribution, pharmacokinetics, pharmacodynamics, noncommunicable and infectious disease by measuring exogenous and endogenous small molecules, lipids, proteins, and peptides in various tissue types.