Curcumin loaded Ag-TiO 2 -halloysite nanotubes platform for combined chemo-photodynamic therapy treatment of cancer cells.

The use of naturally occurring anticancer materials in combination with doped metal oxide has emerged as one of the most promising ways for improving anticancer treatment efficacy. In this study, the anticancer potential of curcumin-loaded Ag-TiO 2 -halloysite nanotubes (curcumin-loaded Ag-TiO 2 -HNTs) was examined. Ag-TiO 2 -HNTs with different wt% of Ag-TiO 2 were synthesized and characterized using XRD, TGA, FT-IR, UV-Vis spectroscopy, and SEM-EDX. The XRD results revealed the presence of crystalline TiO 2 . However, the presence of Ag was detected through the SEM-EDX analysis. Cyclic voltammetry measurements suggested the enhancement of the release of ROS from TiO 2 upon deposition with Ag. FT-IR and TGA analysis confirmed the successful loading of curcumin inside the nanotubes of the halloysite. In vitro drug released studies revealed the release of approximately 80-99% curcumin within 48 hours. Kinetic model studies revealed that the release of curcumin from HNT and Ag-TiO 2 -HNT followed the first-order and Higuchi models, respectively. The light irradiated curcumin-loaded Ag-TiO 2 -HNTs samples exhibited considerable anticancer potential as compared to the free curcumin, irradiated Ag-TiO 2 NPs samples, and unirradiated curcumin loaded Ag-TiO 2 -HNTs samples. The obtained results revealed that combined chemo- and photodynamic therapy using curcumin-loaded Ag-TiO 2 -HNTs nanomaterial has the potential as an effective anticancer treatment method.