For fluorescence imaging and PDT of early melanoma,Yoon et al.developed a novel endogenous tyrosinase-activated cyclometalated Pt(II)complex (136-tyro), by connecting a 3-hydroxybenzyloxymoiety (as the tyrosinase recognition unit) to the phenyl pendentof a C∧N ligand of a cyclometalated Pt(II) complex(as the PSs core).409 As depicted in Figure 74, after reactingwith tyrosinase, 136-tyro was converted into 136-OH through rapid rearrangement and elimination, leading to an obviousfluorescence off-on response at 530 nm. This evidence concerns the gene TYR and melanoma.