MALDI imaging mass spectrometry

Abstract

Matrix assisted laser desorption/ionization imaging mass spectrometry (MALDI IMS) is a powerful tool for the in situ analysis of endogenous biomolecules and exogenous pharmaceutical compounds in thin tissue sections. Hundreds to thousands of analytes can be detected and mapped in a single imaging experiment without a priori knowledge of the exact molecules present in the section. Advances in sample preparation and in instrumentation have allowed for MALDI IMS to become a high throughput technique allowing for statistical analysis and diagnostic classification of clinically important specimens. This review discusses the current state of the technology with regards to advances in sample preparation techniques and instrumentation. These include the expansion of the technique to the analysis of formalin-fixed, paraffin embedded tissues as well as the ability to acquire IMS data at the single cell level. Applications to skin cancer, infectious disease, diabetes, and age-related macular degeneration are highlighted.