Within the volume of a single cell, lines an extensive amount of information. The current scope of molecular imaging using mass spectrometry typically swamps the cell volume with organic acid matrix just to get observable signals. Herein lies the problem. Putting more matrix that there is analyte (i.e. cellular volume) inherently makes intracellular imaging via organic acids improbable. Therefore, Ionwerks has developed a comprehensive set of instrumentation, and nanoparticulate preparation techniques which combine two dimensional ion-mobility mass spectrometry and nanoparticulate tissue preparation which provide a means to analysis of tissues while preserving their histological attributes. Our research has demonstrated that sub-monolayers of nanoparticulates implanted into various depths within a tissue, provide agreeable signal levels. This means, the particulate to analyte ratio is much less that typical preparations: the chemical information is preserved and observable. The nanoparticulates will also be microfocused to allow for unique molecular secondary ion mass spectrometry (SIMS). Furthermore, we are developing small format oTOF MS detectors which can be combined with leading edge surface imaging techniques to create a one of a kind imaging platform from which surfaces / tissues can be morphologically imaged, and mass spectra of ejected ions can be recorded.
The goal of this project is implant histological prepared tissues with gold nanoparticulates, then to measure the ejected ions using a low profile oTOF-MS system from a microfocused nanoparticulate beam. This project will lay the groundwork for utilizing the helium ion-beam microprobe systems as a combined topographical imaging system, as well as molecular imaging systems.
|Jackson, Shelley N; Barbacci, Damon; Egan, Thomas et al. (2014) MALDI-Ion Mobility Mass Spectrometry of Lipids in Negative Ion Mode. Anal Methods 6:5001-5007|