Curcumin encapsulated PLGA-chitosan nanocarrier: Fabrication, characterization, and in vitro differentiation evaluation on PC12 cells

Curcumin, a polyphenolic compound, demonstrates neuroprotective potential through its antioxidant, anti-inflammatory, and anti-amyloid activities. To enhance its delivery, we fabricated poly(lactic-co-glycolic acid) (PLGA) nanoparticles encapsulating curcumin and stabilized them with chitosan. Successful formulation was confirmed by FTIR, XRD, and SEM analyses. Zeta potential measurement confirmed a surface charge reversal from -28.1 mV (uncoated PLGA) to + 14.7 mV after chitosan coating. The nanoparticles exhibited favorable drug loading (4.09 ± 0.02 % to 5.67 ± 0.01 %) and encapsulation efficiency (14.33 ± 0.08 % to 19.85 ± 0.04 %), and provided a sustained release profile (>24 h) enhanced by chitosan. The curcumin encapsulated PLGA-chitosan nanocarriers demonstrated potent antioxidant activity (>80 % DPPH scavenging at 0.75 mg/mL) and no significant cytotoxicity against PC12 cells at concentrations up to 80 μg/mL. In HCT116 cells, the chitosan coating enhanced cellular uptake and cytoplasmic distribution. Crucially, the nanocarriers promoted PC12 cells differentiation, resulting in a high proportion of neurite-bearing cells. These findings indicate that the designed chitosan-coated PLGA nanoparticles are a promising delivery system for promoting neuronal differentiation.