Activity‐based probes can also be used for the cellular imaging of MAOs.[37] The group of Yao designed the dual‐purpose activity‐based probe 12, which showed a formidable selectivity for MAO B (Figure 4).[38] Compound 12 was used for the ABPP of MAO B and live cell bioimaging of MAO B activity in cell and tissue models of Parkinson's disease without encountering diffusion problems. Here, MAOB is linked to Parkinson disease.