Peptide Multifunctionalized Gold Nanorods with Dual pH/NIR Responsive Release of Doxorubicin for High-Efficiency Cancer Treatment

In this study, gold nanorods (GNRs), uniformly coated with polydopamine (PDA), were developed as a multifunctional nanocarrier for targeted, pH, and near infrared (NIR) irradiation dual-stimuli triggered drug delivery. Doxorubicin (DOX), a hydrophobic chemotherapeutic drug, was conveniently and heavily loaded into the nanocarrier through pi -pi stacking and hydrogen bonding interactions. It was further passivated by thiolated poly(ethylene glycol)-tumor homing peptides (NGR and TAT) to improve its cancer tissue penetrating, and accurate targeting ability. The developed NGR/TAT-DOX-PDAOGNRs could not only specifically and effectively deliver therapeutic agents to the tumor sites, but also facilitated controlled release of DOX, triggered via pH and near infrared light dual-stimuli. The studies of tumor cell ablation confirmed that this chemo-photothermal synergistic therapy offered superior therapeutic efficacy, improved chemosensitivity, and enhanced chemotherapeutic efficacy. Therefore, this combination of photothermal therapy and chemotherapy, based on NGR/TAT-DOX-PDAOGNRs, can maximize the therapeutic efficacy, and minimize the dosage-related adverse effects in cancer treatment.