Mitochondria-targeted biotin-conjugated BODIPYs for cancer imaging and therapy†

Two BODIPY–biotin conjugates KDP1 and KDP2 are designed and synthesized for targeted PDT applications. Both have good absorption with a high molar absorption coefficient and decent singlet oxygen generation quantum yields. The photosensitizers KDP1 and KDP2 were found to be localized in the mitochondria with excellent photocytotoxicity of up to 18.7 nM in MDA-MB-231 breast cancer cells. The cell death predominantly proceeded through the apoptosis pathway via ROS production.