Figure 4. DESI/PI-MSI of polyacetylenes and sesquiterpenes selected from rhizome section of JAR. (A) The optimal images of rhizome cross sections of JAR (selected trapezoid patch is marked with red dash line). (B-F) MS images of selected ions (m/z) obtained by DESI/PI. MS images were recorded with a scanning step size of 200 μm.