Ambient mass spectrometry imaging of banana (Musa spp.) tissue with infrared laser-based selected reaction monitoring mass spectrometry imaging

Abstract

In this study, for the first time we present the application of an infrared (IR) laser ablation-remote-electrospray ionization (LARESI) platform coupled to a tandem mass spectrometer (MS/MS) operated in selected reaction monitoring (SRM) or multiple reaction monitoring (MRM) modes for targeted metabolite imaging in intact plant tissues. The primary objective of this study was to investigate the spatial distribution of specific metabolites in banana tissue sections from two commercially available banana varieties: Red Dacca and Cavendish banana (Musa acuminata from AAA banana cultivar group). To support MSI results, an extensive analysis of banana tissue extracts was conducted using ultra-high-performance liquid chromatography and ultra-high-resolution mass spectrometry (UHPLC-UHRMS). In the Cavendish banana, 12 metabolites were successfully identified, while Red Dacca Bananas were found to contain 16 amino acids. The spatial distribution of some of these compounds found in bananas was presented for the first time. The results highlight the potential of the LARESI MSI technique as a highly sensitive and rapid method for targeted imaging of plant tissues. Importantly, this approach eliminates the need for high vacuum conditions and the pretreatment of biological materials, making it an efficient and promising tool for studying metabolites in plant tissues.