Gold nanoclusters as a GSH activated mitochondrial targeting photosensitizer for efficient treatment of malignant tumors

Gold nanoclusters (Au NCs), which have the characteristics of small size, near infrared (NIR) absorption and long triplet excited lifetime, have been used as a new type of photosensitizer for deep tissue photodynamic therapy (PDT). However, the therapeutic efficiency of the nano-system based on Au NCs still needs to be improved. Herein, we proposed a strategy using Mito-Au(25)@MnO(2) nanocomposites to achieve enhanced PDT. Au(25)(Capt)(18)(−) nanoclusters were applied as photosensitizers and further modified with peptides to target mitochondrial and MnO(2) nanosheets to consume glutathione (GSH). In the presence of GSH, Mito-Au(25)@MnO(2) dis-integrated and Mito-Au(25) nanoparticles realized accurate mitochondrial targeting. Under the irradiation of 808 nm light, the nanocomposite ensured highly efficient PDT both in vitro and in vivo via oxidation pressure elevation and mitochondrial targeting in cancer cells.