Advancements in Cryogenic Electron and Mass Spectrometry Imaging Enhance Subcellular Chemical Mapping
Recent developments in cryogenic electron and mass spectrometry imaging have significantly advanced the field of subcellular chemical mapping. The integration of cryo-EM-FIB-SIMS (cryo-focused ion beam secondary ion mass spectrometry) with existing correlative light and electron microscopy (CLEM) workflows has enabled researchers to achieve a larger field of view for target identification. This method allows for dual labeling strategies that incorporate both chemical and fluorescent tags, enhancing the ability to visualize and analyze biological specimens at a molecular level. The technique involves the use of gold nanoparticle-tagged bacterial cells and differential fluorescent labeling, which provides detailed spatial and compositional information about subcellular features. The cryo-EM-FIB-SIMS method directly detects secondary ions produced during the interaction between a primary ion beam and the sample, allowing for the detection of elemental, molecular, and isotopic secondary ions. This advancement ... 
