Fig. 4: Total brain concentrations determined by MALDI-qMSI.

a Representative images showing the relative abundance and distribution of risperidone (left), clozapine (middle), and olanzapine (right) in in vivo and in vitro brain tissue sections. Representative images were measured with a lateral resolution of 40 µm and concentrations are shown using a logarithmic scale, scaled to 0–100% (the scale bar is 1 mm). Data for determination of total concentrations were acquired at 100-µm lateral resolution and normalized against a deuterated drug analogue. b Scatter dot plots of the total drug concentrations (ng g⁻¹) in entire brain sections from in vivo (n = 6 per group) and in vitro (n = 3 per group) experiments. c Scatter dot plots of region-annotated total concentrations obtained from in vivo neuroPK studies, and d in vitro rat brain-slice assays. The steady-state total concentrations achieved in vivo (C_tot,brain,ss) and in vitro (C_{tot,br.slice,ss}) are shown as a reference line with the mean ± the standard deviation from the mean (gray shaded area). cc corpus callosum, ec external capsule, aca anterior commissure, CgCx cingulate cortex, MCx motor cortex, SCx somatosensory cortex, InCx insular cortex, Pir piriform cortex, CPu caudate putamen, NAc nucleus accumbens, LS lateral septum. Only statistically significant differences (P < 0.01) are shown. Note the differences in scale in figures b–d.