Fig. 4.

3D-surface MALDI MS imaging of A. curassavica leaf that was wounded proximal and distal after vein-cutting. a Optical microscopic image of the leaf surface before the measurement. Area of exuded latex on the leaf surface is marked. b Topographic image of the leaf surface showing height differences up to 700 μm at the primary leaf vein. c, d RGB overlay of ion images showing the spatial distribution of c uscharin (m/z 626.2189, [M + K]⁺, red), d pheophytin a (m/z 909.5291, [M + K]⁺, red), c, d malonylgenistin (m/z 557.0692, [M + K]⁺, green) and a background signal of the MALDI target c, d at m/z 771.4869 (blue). MS images were generated with 157 × 171 pixels; 40 μm pixel size; m/z bin width: Δ(m/z)/m/z = ± 5 ppm. The scale bars are 1 mm