Hollow gold nanoshells-incorporated injectable genetically engineered hydrogel for sustained chemo-photothermal therapy of tumor

Background Combined therapy has demonstrated to be an effective strategy for cancer therapy. Herein, an injectable hydrogel based on the genetically engineered polypeptide and hollow gold nanoshells (HAuNS) has been developed for chemo-photothermal therapy of HepG2 tumor. Methods PC 10 A/DOX/HAuNS nanogel was prepared with layer-by-layer through the adsorption of DOX and PC 10 A successively. DOX with positive charge and PC 10 A with negative charge were coated step by step onto the surface of negatively charged HAuNS. The multifunctional hydrogel PC 10 A/DOX/HAuNS were prepared via dissolving hybrid PC 10 A/DOX/HAuNS nanogel in polypeptide PC 10 A. Chemotherapy drug DOX in the PC 10 A/DOX/HAuNS hydrogel was absorbed on the HAuNS and directly embedded in the PC 10 A hydrogel, which contributes to sequentially release of the drug. Specifically, DOX adsorbed on the HAuNS could be released slowly for sustainable chemotherapy. Results The PC 10 A/DOX/HAuNS hydrogel could pass 26-gauge needle without clogging, indicating that it is injectable. In addition, the PC 10 A/DOX/HAuNS hydrogel possessed outstanding photothermal effect and photothermal stability. In both in vitro cell and in vivo tumor-bearing mice experiments, a remarkably enhance tumor inhibition was observed by the combined therapy of chemo-photothermal therapy compared with photothermal therapy or chemotherapy alone. Conclusions The combined chemotherapy and photothermal therapy of PC 10 A/DOX/HAuNS hydrogels could significantly improve the therapeutic effect. Therefore, the multifunctional hydrogel PC 10 A/DOX/HAuNS is promising to provide a new strategy for sustained chemo-photothermal therapy.