a–j, ToF-SIMS positive and negative ion images of a cholesterol fragment at C7H11+, m/z 95.07 (a), myristic acid at C14H27O2−, m/z 227.22 (b), palmitoleic acid at C16H29O2−, m/z 253.23 (c), linoleic acid at C18H31O2−, m/z 279.25 (d), phosphocholine fragment at C5H13NPO3+, m/z 166.05 (e), phosphocholine at C5H15NPO4+, m/z 184.04 (f), H3O+ at m/z 19.02 (g), OH− at m/z 17.00 (h), Na+ at m/z 22.99 (i), and K+ at m/z 38.96 (j). Additional secondary ion images for Fig. 1 are provided here for extra information. Scale bar, 100 μm (a–j). Results presented are obtained from a single experiment.