A Photoactive Antibacterial Hydrogel Incorporated with Bi2S3 Nanoparticles, Cancer Cell Membrane, and Sorafenib for Localized Photo-chemo-immunotherapy of Cancer

Aim and Background: Bi2S3 nanorods (NRs) are promising photothermal agents for cancer therapy due to their light-to-heat conversion ability to induce apoptosis in tumor cells. Combination of PTT with chemotherapy and immunotherapy has a high potential to increase the chance of cancer eradication without metastasis to other vital organs. In this work, cancer cell-membrane (CCM) and sorafenib (SFN) were loaded into a photoactive injectable hydrogel to render tumor-specific immunotherapeutic function and chemotherapy to the prepared hydrogel. Methods: Bi2S3 NRs were prepared using a simple chemical reaction and coated with hyaluronic acid to form BiH NRs. An injectable hydrogel was prepared via chemical crosslinking and incorporated with BiH NRs, CCM, and SFN. The physicochemical characterization and photothermal performance of the NRs and hydrogels, in vivo toxicity, the antibacterial activity, and its anti-cancer effect were evaluated on a 4T1 tumor-bearing mouse model. Results and discussion: The rod shape nanoparticles, with an average particle size of about 57 nm were successfully loaded into the chemically crosslinked hydrogel, which had good injectability. BiH NRs demonstrated sufficient temperature elevation to kill cancer cells after 10 min of near-infrared (NIR) irradiation. In addition, the BiH-loaded hydrogel showed potent antibacterial activity. The combined intratumoral photo-chemo-immunotherapy demonstrated more anticancer effects than the individual photo-, chemo- or immunotherapy alone. Conclusion: In this study, an injectable hydrogel containing BiH NRs, CCM, and SFN is reported for cancer ablation via a synergistic effect. In addition, the injectable hydrogel had the capability to load drugs for sustained release at the cancer tissues over a long period.