A water soluble donor–acceptor–donor conjugated oligomer as a photosensitizer for mitochondria-targeted photodynamic therapy

Abstract

We designed a water soluble benzotriazole-cored donor–acceptor–donor molecule bearing four triphenylphosphonium moieties for mitochondria targeting. The organic molecule showed strong singlet oxygen sensitizing capability (Φ_Δ 0.64), minimal dark cytotoxicity and high photocytotoxicity. The molecule is efficient in photodynamic killing of tumour cells under normal and hypoxia conditions using a very low light flux, and has potential in near-infrared two-photon imaging and photodynamic therapy.