Self-assembly of hydroxyapatite around Ti3C2 MXene/gold nanorods for efficient remotely triggered drug delivery

Ti 3 C 2 MXene/gold nanorods (Ti 3 C 2 @AuNRs) nanosheets , a novel sandwich-like nanohybrids , have attracted extensive attention in the biomedical field due to its synergistically enhanced near-infrared (NIR) responsiveness and strong absorption in NIR region. In this study, hydroxyapatite (HAP) was self-assembled in situ around Ti 3 C 2 @AuNRs core and then combined with polydopamine (PDA) to prepare NIR-/pH- dual responsive Ti 3 C 2 @AuNRs/HAP/PDA nanocomposites. The obtained Ti 3 C 2 @AuNRs/HAP/PDA nanocomposites exhibited prominent photothermal conversion efficiency (38.6%) due to the synergistically enhanced NIR-responsive of Ti 3 C 2 @AuNRs. Ti 3 C 2 @AuNRs/HAP/PDA nanocomposites displayed excellent drug loading capacity (88.3%) for antitumor drug doxorubicin hydrochloride (DOX) because of the electrostatic interaction of negatively charged HAP nanorods and positively charged DOX, along with the distinct adhesiveness of PDA. In addition, the disintegration of HAP under acid medium and the strong NIR absorption of Ti 3 C 2 @AuNRs endowed the Ti 3 C 2 @AuNRs/HAP/PDA nanocomposites with pH-/NIR-dual responsive drug release behavior. In this paper, a feasible method is presented to prepare Ti 3 C 2 -based drug carriers with high drug loading capacity and remarkable multi-responsive drug release properties, which holds great promise in the field of remote controlled drug delivery and photothermal therapy.