Construction of polyethylene glycol-cloaked mesoporous polydopamine nanomaterials co-loaded with anticancer drugs for photo/chemotherapy of lung cancer cells and elucidation of the cell death mechanism

Lung cancer is one of the leading causes of cancer-related deaths worldwide. The mortality rate can be reduced through the development of novel therapeutic drugs for lung cancer. In this study, we developed nanoparticles (NPs) consisting of polyethylene glycol (PEG)-cloaked mesoporous polydopamine (MP) loaded with indocyanine green (IG) and talazoparib (TZ), designed to combine therapies for lung cancer. MP NPs were synthesized and surface-capped with methoxypolyethylene glycol amine. PEG2K-MP and PEG5K-MP NPs were analyzed using dynamic light scattering, scanning electron microscopy, and transmission electron microscopy. PEG2K-MP@IG&TZ and PEG5K-MP@IG&TZ NPs were developed using the solvent diffusion technique to co-load IG and TZ. The reduction in drug-feeding ratios led to a decrease in the amount of drug loaded and an increase in the encapsulation efficiency. PEG2K-MP@IG&TZ and PEG5K-MP@IG&TZ NPs, which showed excellent drug loading efficiency (IG: 9.9 ± 0.4% and 9.1 ± 0.2%; TZ: 6.8 ± 0.3% and 6.5 ± 0.2%), were chosen for further investigation. The hydrodynamic sizes ranged from 200 to 300 nm. These nanoparticles exhibited improved stability of IG in water, near-infrared laser-stimulated release of TZ, effective photothermal activity, excellent biocompatibility, and increased cellular uptake. These two nanoparticles demonstrated a stronger anticancer effect on lung cancer A549 cells than the combination of IG and TZ when irradiated with 808 nm light in vitro. Fluorescence microscopy revealed that PEG5K-MP@IG&TZ NPs efficiently triggered apoptosis in A549 cells. This study presents an innovative and efficient method for combination therapy against lung cancer cells.