Plasmonic liposomes for synergistic photodynamic and photothermal therapy

In the present study, plasmonic liposomes (PLs) loaded with photosensitizers were developed for synergistic photodynamic and photothermal therapy. These PLs were prepared by incorporating a photosensitizer, ZnPc, into the liposomal membrane for photodynamic therapy (PDT) and coating a gold nanofilm onto the surface for photothermal therapy (PTT). The gold coating was optimized to efficiently absorb the wavelength of light at which ZnPc is activated for PDT. The photosensitizing effect of ZnPc was synergistically enhanced upon single light irradiation due to local photothermal heating and the surface plasmon resonance of the gold nanostructure. Furthermore, combined photodynamic and photothermal therapy using ZnPc-PLs exhibited a remarkably enhanced therapeutic efficacy on cancer cells in vitro compared to PDT or PTT alone. Therefore, we believe that this dual photoactive nanodevice with a synergistic therapeutic index has great potential to improve the current phototherapy of cancer.