In situ growth of nano-hydroxyapatite on multilayered Ti3C2Tx MXene as a drug carrier with superior-performance

Bone defects caused by tumor resection typically require bone repair materials to fill the defect sites. The development of multifunctional bone filling materials with integrated chemotherapy, photohermal therapy, and guided bone regeneration is very necessary and urgently needed. Herein, for the first time, the construction of novel multilayered Ti3C2Tx MXene (m-MXene)/nano-hydroxyaptite (nHAp) composites (m-MXene/nHAp) for bone repair is reported. The in situ growth of nHAp on multilayered Ti3C2Tx MXene is achieved through a facile hydrothermal method without using any organic additives. Due to the synergistic effects of nHAp and m-MXene, the m-MXene/nHAp composites show superior drug carrier performance with ultra-high drug loading capacity and ultra-long drug sustained release time. The molecular dynamics simulation results indicate that both Ti3C2Tx MXene and HAp show many adsorption sites and high binding energy with DOX. Moreover, the m-MXene/nHAp composites possess high photothermal conversion efficiency and excellent photothermal stability. The in situ growth of nano-HAp can significantly improve the biocompatibility of the m-MXene. The as-prepared multifunctional m-MXene/nHAp composites in this work can be used as bone filling powder and have great potential in bone defect reconstruction caused by bone tumor.