Novel PVA-Based Microspheres Co-Loaded with Photothermal Transforming Agent and Chemotherapeutic for Colorectal Cancer Treatment

Background: We previously designed an electrospinning chitosan (CS) nanofiber-based carrier, using polyvinyl alcohol (PVA) as an adjuvant to deliver doxorubicin (DOX) and MoS2 nanosheets for postoperative tumor re-occurrence inhibition. However, owing to that the nanofibrous mat is un-injectable, this composite nanofiber is far from being clinically applicable. Materials and Methods: Via modulating the electrospray parameters, polyvinyl alcohol (PVA) beads string doped with DOX and MoS2 (PVA/MoS2/DOX microspheres) were prepared, which were further crosslinked with glutaraldehyde to obtain the water-stability. Results: Under the 808-nm laser irradiation, MoS2 nanosheets rendered the prepared PVA/MoS2/DOX microspheres an excellent light-to-heat conversion performance with η of 23.2%. Besides, the heat generated by near-infrared laser irradiation can improve the effect of chemotherapy by promoting the release rate of DOX. HT29 cell and tumor-bearing nude mice were used to systematically study the combined tumor treatment efficiency of composite nanospheres. Conclusion: PVA/MoS2/DOX nanospheres have excellent photothermal effect and chemotherapy effect, which can completely suppress the tumor recurrence. Therefore, the PVA/MoS2/DOX nanospheres are anticipated to find potential applications in the treatment of local colorectal cancer.