Therapeutic Nanoparticles Based on Curcumin and Bamboo Charcoal Nanoparticles for Chemo-Photothermal Synergistic Treatment of Cancer and Radioprotection of Normal Cells.

Low water solubility, extensive metabolism, and drug resistance are the existing unavoidable disadvantages of the insoluble drug curcumin in biomedical applications. Herein, we employed d-α-tocopherol polyethylene glycol 1000 succinate (TPGS)-functionalized near-infrared (NIR)-triggered photothermal mesoporous nanocarriers with bamboo charcoal nanoparticles (TPGS-BCNPs) to load and deliver curcumin for improving its bioavailability. This system could considerably increase the accumulation of curcumin in cancer cells for enhanced curcumin bioavailability via simultaneously promoting the cellular internalization of the as-synthesized composite (TPGS-BCNPs@curcumin) by the size effect of NPs and considerably triggering controlled curcumin release from TPGS-BCNPs@curcumin by NIR stimulation and reducing efflux of curcumin by the P-glycoprotein (P-gp) inhibition of TPGS, so as to enhance the therapeutic effect of curcumin and realize a better chemo-photothermal synergetic therapy in vitro and in vivo. Besides cancer therapy, studies indicated that curcumin and some carbon materials could be used as radical scavengers that play an important role in the radioprotection of normal cells. Hence, we also investigated the free-radical-scavenging ability of the TPGS-BCNPs@curcumin composite in vitro to preliminarily evaluate its radioprotection ability for healthy tissues. Therefore, our work provides a multifunctional delivery system for curcumin bioavailability enhancement, chemo-photothermal synergetic therapy of cancer, and radioprotection of healthy tissues.