Live dead kit

CCK8 assay: Cells were plated in 96-well plates (2000 cells/well in 100 µL), cultured overnight, and incubated with 0, 0.99, 2.96, 8.89, 26.67 and 80 μg mL⁻¹ NPs for 24 h. Then, 10 µL of cell counting kit-8 (CCK-8, Dojindo, Japan) was added, and the cells were incubated at 37 °C in the dark for 4 h. The optical density at 450 nm was determined with a microplate reader. Live/dead, EdU, and ROS measurements: OCM1a cells were pretreated for 24 h with PBS, 15 µg mL⁻¹ ICG-MOF-PR, ICG-OP@MOF-PR, ICG-Cis@MOF-PR and ICG-COP@MOF-PR. Cell survival (calcein AM staining) and death (PI staining) were assessed using a live/dead kit (Beyotime, China) according to recommended procedures. Cell proliferation was studied using a Cell-Light EdU Apollo488 In Vitro Kit (RiboBio, China) following the manufacturer’s instructions. The ROS levels were assessed using a DCFH-DA assay (Beyotime, China) according to recommended procedures. Images were taken with a fluorescence microscope (Nikon).

Rat Schwann cells (RSCs) were provided by the Chinese Academy of Sciences (Shanghai, China). The MXene-PCL and PCL film were soaked in 75% alcohol and rinsed repeatedly with PBS at least three times. Then, they were placed in a sterile Petri dish, dried in a fume hood, and irradiated on the front and back sides for 2 h separately to achieve sterilization by an ultraviolet lamp. We seeded the cells on the PCL side of MXene-PCL scaffolds, PCL scaffolds, and TCP at a density of 2 × 10⁴ cm⁻². After incubation for 24 h, a LIVE/DEAD kit (Beyotime, China) was used for cell viability analysis according to the standard protocols. Finally, cells in each group were photographed under a fluorescence microscope.

Tumor spheroids with a diameter of approximately 400 μm were coincubated with different formulations for 48 h (Enz: 50 µg·mL^− 1, miR26a: 1 µg·mL^− 1). The cytotoxicity was evaluated by a Live/Dead Kit (Beyotime), and all images were captured by CLSM.