Synthesis of cationic gel-coated hydroxyapatite composites for pH- and thermo-responsive drug delivery in tumor microenvironments

Nanomedicine has gained a significant attention in biomedical science and engineering. It involves design and applications of engineered composites for targeted delivery, diagnostics, imaging, and therapeutic efficacy assessment. Herein, multi-stimuli responsive doxorubicin (DOX) loaded composites were prepared and used for controlled anticancer drug release for antitumor efficacy. In this study, we synthesized the HAp@PP composites by coating Pluronic® P123 and branched polyethylenimine (PP nanogel) on hydroxyapatite (HAp) particles. In-vitro cytotoxicity tests emphasized that HAp@PP composites presented a cell viability of more than 80 % before DOX loading. The fabricated HAp@PP–DOX composites indicated a pH-/thermo-reliant DOX release under tumor microenvironment conditions. Furthermore, the Korsmeyer-Peppas kinetic model yielded the best fit for the release of DOX under the conditions studied. The in-vitro assessment revealed that HAp@PP–DOX had a higher effect that free DOX, with a cell viability less than 25 % and 15 %, respectively, at a DOX concentration of 50 μg/mL. In the context of cancer treatment, the composites have the potential to be more effective than traditional chemotherapy by delivering drugs efficiently.