Gold nanoshell-based betulinic acid liposomes for synergistic chemo-photothermal therapy

Abstract A novel synthesis approach is first developed to fabricate a multifunctional smart nanodrug delivery system: gold nanoshell-coated betulinic acid liposomes (AuNS-BA-Lips) mediated by a glutathione. The AuNS-BA-Lips exhibited good size distribution (149.4 ± 2.4 nm), preferable photothermal conversion ability and synergistic chemo-photothermal therapy. Additionally, the absorption wavelength of AuNS-BA-Lips showed a significantly red-shifted to near infrared (NIR) region, which can strongly absorbed NIR laser and efficiently convert it into localized heat, thus providing controlled drug release and antitumor thermotherapy. Moreover, the nanocarriers excited by NIR light significantly promoted cell uptake compared to those without irradiation, resulting in an enhanced intracellular drug accumulation. Upon NIR irradiation, the AuNS-BA-Lips showed highly efficient antitumor effects on tumor-bearing mice with an inhibition rate of 83.02%, thus demonstrating a remarkable synergistic therapeutic effect of chemotherapy and thermotherapy. Therefore, this work provides new insight into developing a multifunctional antitumor drug.