Complementary UV-MALDI and IR-MALDESI Imaging Expand Metabolomic Coverage in the 6-OHDA Rat Model of Parkinson’s Disease

In this study, we demonstrate the complementary strengths of FMP-10 (4-(Anthracen-9-yl)-2-fluoro-1-methylpyridin-1-ium iodide) on-tissue derivatization with UV-MALDI MSI and IR-MALDESI MSI without derivatization for small molecule analysis. These MSI approaches were applied to the striatum of rats administered 6-OHDA to induce dopaminergic neurodegeneration, modeling Parkinson's disease. UV-MALDI MSI with FMP-10 derivatization enhanced the detection of dopaminergic and serotonergic metabolites, revealing clear lesion-related effects. IR-MALDESI MSI, in turn, expanded the molecular coverage by detecting several hundred additional small molecules, including neurotransmitters, amino acids, and lipids. The complementary application of these ionization strategies broadened metabolomic coverage, highlighting their potential for broader disease-related studies.