Lysosome Specific Platinum(II) Catecholates with Photoactive BODIPY for Imaging and Photodynamic Therapy in Near‐IR Light

Platinum(II)‐BODIPY (boron‐dipyrromethene) complexes of 1,2‐diaminocyclohexane (dach), [Pt(dach)(ML)] ( MP ) and [Pt(dach)(IML)] ( IMP ), where H 2 ML is morpholine‐appended O,O‐donor mono‐styryl BODIPY‐appended catecholate and H 2 IML is di‐iodinated morpholine‐conjugated O,O‐donor mono‐styryl BODIPY linked catecholate, were prepared for photodynamic therapy in near‐IR light (600–720 nm) by targeting lysosomes. Complex MP exhibited a band at 596 nm ( ϵ =2.9×10 4  M −1  cm −1 ) and IMP at 710 nm ( ϵ =2.6×10 4  M −1  cm −1 ) within PDT window in dimethyl sulfoxide (10 %)/Dulbecco's Modified Eagle's Medium (DMSO/DMEM, pH 7.2). Complexes MP and IMP showed red emission ( λ em ) at 615 nm ( λ ex =580 nm, Φ F =0.04) and 718 nm ( λ ex =685 nm) ( Φ F , fluorescence quantum yield) in DMSO (10 %)‐DMEM (pH 7.2). Emissive complex MP showed lysosome‐specific localization in cellular imaging study. Complex IMP showed photocytotoxicity in near‐IR light of 600–720 nm (IC 50 : 0.86–1.2  μ M) with apoptotic cell death forming singlet oxygen in a type‐II pathway.