Single 808 nm Laser Treatment Comprising Photothermal and Photodynamic Therapies by Using Gold Nanorods Hybrid Upconversion Particles

© 2018 American Chemical Society.Light therapy has become the subject of research on cancer treatment because of its selectivity, low invasive damage, and side effects. Photothermal therapy (PTT) and photodynamic therapy (PDT) are prevalent treatments used to induce cancer cell apoptosis by generating heat and reactive oxygen species (ROS). In this study, mesoporous silica shell-coated gold nanorods (AuNR@mS) are synthesized by seed crystal growth method. AuNR@mS are assembled into nanocomposites through electrostatic adsorption with lanthanide-doped upconversion nanoparticles (UCNP). When controlling the aspect ratio of gold nanorods (AuNRs), the surface plasmon resonance peaks of the short-axis and the long-axis match the maximum absorption cross section at 520 and 660 nm of the fluorescence light released by the UCNPs. The converted fluorescence stimulates AuNRs to generate heat through energy transfer. ROS production is induced by loading the photosensitizer Merocyanine 540 (MC540) in the mesoporous silica layer and is further enhanced through the surface plasma resonance effect of the AuNRs. This novel nanoplatform combines PTT and PDT in a single 808 nm near-infrared synergistic light therapy.