(A) MALDI-MSI analysis of distributions of cassette- and discrete-dosed drugs (moxifloxacin, olanzapine, erlotinib, and terfenadine) in rat kidney sections (14 μm) at 2 and 6 h post dose. Moxifloxacin and olanzapine distributions are comparable at the two time points validating the cassette dosing approach. Printed with permission from [110]. Copyright 2022, ACS. (B) MALDI-MSI ion map of selected ions including imatinib (green), endogenous phospholipid PC (34:1) (blue), and PC (32:0) (red) in kidney section at 35 μm resolution. Adapted with permission from [111]. Copyright 2022, Springer. (C) Overlay MSI image of selected ions including imatinib (green), endogenous phospholipid PC (38:5) (blue), and heme (red) in kidney section at 10 μm resolution. Adapted with permission from [111]. Copyright 2022, Springer.