Gold Nanorods@Mesoporous SiO₂@Hyaluronic Acid Core–Shell Nanoparticles for Controlled Drug Delivery

To improve the therapeutic efficacy of breast cancer (BC), an intelligent tri-responsive vehicle based on core–shell structured gold nanorods (GNR)@mesoporous SiO2 (MS)@hyaluronic acid (HA) is proposed for controlled delivery of methotrexate (MTX). The characterization of the resultant GNR@MS@HA is systematically investigated. GNR is used for photothermal conversion under near-infrared light (NIR) irradiation, and the produced hyperthermia can lead to the ablation of cancer cells. MTX can be encapsulated in the mesopores of MS with the aid of HA, which is grafted to the surface of aminated MS (MS-NH2) through amidation reaction. The proposed vehicle can be used for MTX release in the tri-response of pH, NIR, and hyaluronidase (HAase) and integrates photothermal therapy and chemotherapy so as to improve the inhibition rate of cancer cells. The results of cell viability experiments demonstrate that the developed tri-responsive vehicle displays excellent biocompatibility to L929 mouse fibroblasts while exhibiting high chemo-photothermal synergistic therapy efficiency against murine BC cells (4T1).