Mesoporous Polydopamine Nano-Bowls Demonstrate a High Entrapment Efficiency and pH-Responsive Release of Paclitaxel for Suppressing A549 Lung Cancer Cell Proliferation In Vitro.

The effectiveness of paclitaxel (PTX) in treating non-small-cell lung carcinoma (NSCLC) is restricted by its poor pharmacokinetic profile and side effects. This limitation stems from the lack of a suitable delivery vector to efficiently target cancer cells. Therefore, there is a critical need to develop an efficient carrier for the optimised delivery of PTX in NSCLC therapy. The present study describes the fabrication of mesoporous polydopamine (mPDA) nano-bowls via an emulsion-induced interfacial anisotropic assembly method, designed for efficient entrapment of PTX and pH-responsive release behaviour. The nano-bowls depicted a typical bowl-like shape, with connecting mesoporous channels and a central hollow cavity, allowing optimal loading of PTX. The fabricated nanocarrier system, mPDA-PTX-nb, had a mean hydrodynamic bowl diameter of 200.4 ± 5.2 nm and a surface charge of -39.2 ± 1.3 mV. The entrapment efficiency of PTX within the nano-bowls was found to be 95.7%, with a corresponding release of 85.1% achieved at the acidic pH 5.9 (simulated tumour microenvironment) at 48 h. Drug release was best fitted to the Peppas-Sahlin model, indicating the involvement of both diffusion and relaxation mechanisms. Treatment with mPDA-PTX-nb significantly suppressed A549 lung cancer cell proliferation at 48 and 72 h, resulting in cell viability of 14.0% and 9.3%, respectively, at the highest concentration (100 µg/mL). These results highlight the potential of mPDA-PTX-nb as an effective nanocarrier for PTX, promoting enhanced anti-proliferative effects in NSCLC therapy.