Cck 8 proliferation kit

The CCK-8 proliferation kit (Dojindo, Kumamoto, Japan) was used for cell proliferation detection. The cells were treated with 0.25% trypsin, followed by the addition of Dulbecco’s modified eagle’s medium (DMEM) to the triturate into individual cells. Following after, the cells were resuspended in stem cell medium for subsequent use. After the cell density was adjusted, the cells were seeded into a 96-well plate with 1000 cells per well in 100 μL culture medium, and the plate was gently rotated to achieve uniform dispersion. The cells were then cultured in an incubator under stable conditions of 37 °C with 5% CO₂ with saturated humidity. A total of 10 μL CCK-8 reagent was added at 0 h, 12 h, 24 h, 48 h and 72 h, respectively, shaken gently, and mixed evenly. After incubation at 37 °C for 2 h, the optical density (OD) of each well was measured using an enzyme-linked immunosorbent assay (450 nm measuring wave). Each group experiment was performed in quintuplicate with a minimum of three independent experiments.

Cardiomyocytes were seeded in 96-well plates at a density of 1 × 10⁴ cells/well and cultured for 24 h. PCM-MSN@LA was added into the cells in triplicate at various concentrations of 0.05, 0.1, 0.2, 0.4, 0.6, 0.8, and 1 mg mL⁻¹, respectively. After incubating for 24 h, the cells were collected and stained with a CCK-8 proliferation kit (Dojindo, CK04) The absorbance was measured at 450 nm.