ToF-SIMS imaging mass spectrometry of microbial systems

Organic biomarkers may greatly aid in the interpretation of geobiological systems, but their significance is often restricted by the loss of spatial information during conventional sample work-up (solvent extraction). Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) is a quasi-non-destructive technique that simultaneously detects inorganic and organic molecules on solid surfaces, without the need to extract the sample in question (Fig. 1). Moreover, ToF-SIMS is capable of generating images displaying the intensities of any ion detected on a microscopic scale, thus exceeding by far the resolution achievable with the extract-based techniques routinely used in biomarker studies.