Formulation, physicochemical characterizations, and stability profiling of palbociclib-loaded polymeric nanoparticle with antioxidant and anti-inflammatory investigation for breast cancer treatment

Background: Breast cancer is a highly prevalent malignancy worldwide with significant mortality, and conventional chemotherapy is often constrained by poor solubility, non-targeted distribution, and systemic toxicity, necessitating improved therapeutic approaches. Methodology: Palbociclib-loaded nanoparticles were formulated using chitosan, PVA, and sodium tripolyphosphate, characterized physicochemically, and evaluated for compatibility, bioactivity, stability, and MCF-7 cytotoxicity via MTT assay. Results and Discussion: PNs loaded with Palbociclib showed λmax at 342 nm, which was significantly linear between the range of 5−40 µg/ml (R² = 0.997). The particle size was 237.8 ± 1.76 nm, the PDI was 0.221, and the zeta potential was +34.09 ± 3.38 mV. The encapsulation efficiency and drug loading were 81.21 ± 1.80% and 43.0 ± 1.64%, respectively. The release was more sustained at pH 5.4 (93.25 ± 0.95%) than at pH 7.4 (80.78 ± 1.51%) after 24 h (p < 0.0001). The antioxidant activity (DPPH IC₅₀ = 0.52 µg/ml) and anti-inflammatory activity (IC₅₀ = 38.9 µg/ml) were better than free palbociclib (2.041 and 137.87 µg/ml). There was no significant change in the size (240.14 ± 1.91 nm), the PDI 0.283, the zeta potential +30.01 ± 2.68 mV, the loading of the drug (40.1 ± 1.58%), and the entrapment efficiency (79.02 ± 2.69%) after three months. PB-PNs resulted in a more pronounced proliferation inhibition effect in MCF-7 cells (IC₅₀ = 5.85 µg/ml) as compared to the free palbociclib (18.15 µg/ml).Conclusion: The developed PB-PNs constitute a stable, pH-responsive, and enhanced anticancer therapy, meriting further in vivo investigation.