Extended Data Fig. 5: Hematoxylin & eosin staining and mass spectrometry imaging of injection site tissues.
a) Tissue sections from mice that received subcutaneous injections of bortezomib alone or in a hydrogel at 1-, 7-, and 21-days stained with hematoxylin & eosin. Large dark purple sections in K2, nitroCat-K2, and SHA-K2 are the hydrogels in the skin samples. b) Mass spectrometry imaging of the same tissue samples stained with hematoxylin & eosin shows that bortezomib signal does not significantly overlap with that from heme (616.178 m/z), illustrating that the drug observed in the tissue is not in circulation but in the local environment of the injection site.
