Mesoporous Manganese Dioxide Coated Gold Nanorods as a Multiresponsive Nanoplatform for Drug Delivery

Nanomaterials can offer a chance to integrate many excellent physical and chemical performances into a single carrier for smart responsive drug delivery. Herein, gold nanorods/mesoporous manganese dioxide (Au/MnO2) hybrid nanoparticles were prepared to combine the photothermal effect of gold nanorods (AuNRs) with glutathione (GSH)-responsive and pH-responsive performances of MnO2. The near-infrared (NIR) responsive constituent of a Au/MnO2 nanoparticle was AuNRs. Doxorubicin hydrochloride (DOX), a widely used anticancer drug, was loaded into the Au/MnO2 hybrid nanoparticle via electrostatic force, hydrogen bonding, and physical absorption with a drug loading up to 99.1%. The results revealed that the mesoporous MnO2 was degraded in the media with high concentrations of GSH and acid microenvironment. The Au/MnO2 nanoparticles displayed satisfying drug release kinetics (ca. 47% of loaded drug released in 12 h) and showed excellent GSH-responsive, pH-responsive, and NIR-responsive performances. This multiresponsive nanoplatform is expected to have wide biomedical application for cancer therapy such as photothermal therapy, drug delivery, and tumor microenvironment improvement.