Cerium ferrite @ molybdenum disulfide nanozyme for intracellular ROS generation and photothermal-based cancer therapy

Two-dimensional (2D) nanomaterial hybrid with metal nanoferrite nanoparticles will enhance their catalytic activity and photothermal therapy (PTT) through their synergistic coupling effects. This strategy also increases the photothermal conversion efficiency (PCE), blood circulation time, biostability, and cellular uptake efficiency of 2D materials. Herein, we first time report a new class of cerium ferrite (CeFe2O4) nanoparticles (NPs) decorated onto branched polyethyleneimine (bPEI) coated flower-like molybdenum disulfide nanoflowers (MoS2 NFs). The CeFe2O4 NPs on the MoS2 NF surface could be designed rationally to improve deficiencies and refine the PCE of MoS2 NFs and tumor ablation effectiveness in the treated MDA-MB-231 breast cells. Importantly, MoS2-bPEI-CeFe2O4 NFs consist of MoS2 in the inner core and CeFe2O4 in the outer shell, designed to generate heat efficiently and enhanced intracellular reactive oxygen species (ROS) generation in the tumor environment. Furthermore, using sheep blood cells, bare MoS2 and MoS2-bPEI-CeFe2O4 NFs showed hemolytic activity levels of 6 and 2.7 %, respectively. Moreover, MoS2-bPEI-CeFe2O4 NFs exhibit 53.6 % of PCE, which effectively induced up to 80 % cytotoxicity and higher levels of ROS generation in the MDA-MB-231 cells when exposed to the 808 nm NIR laser (1.5 W/cm2, 5 min). These findings demonstrate the unique CeFe2O4 NPs with MoS2 NF as a powerful nanozyme for dual-performance cancer therapies (PTT and ROS generation) and reveal a novel PCE refinement strategy for MoS2 NFs. It was successfully established as a new cancer therapeutic platform.