Lecithin-Coated PLGA Nanoparticles for Pulmonary Targeting of Naringin: Formulation, Optimization and In Vitro Characterization.

Chronic obstructive pulmonary disease (COPD) is a progressive respiratory disorder characterized by persistent airflow limitation and chronic airway inflammation. Current therapeutic strategies primarily offer symptomatic relief and are often limited by systemic side effects, inadequate lung deposition, and poor patient compliance. Naringin (NAR), a natural flavonoid with strong antioxidant, anti-inflammatory, and anti-fibrotic activities, has demonstrated potential in mitigating COPD-associated pathophysiology. However, its therapeutic application is restricted by poor water solubility, low bioavailability, and rapid metabolism. Nanotechnology-based drug delivery systems, particularly poly(lactic-co-glycolic acid) (PLGA) nanoparticles, provide an effective approach for lung-targeted therapy. Their nanoscale size promotes deep lung deposition, enhanced cellular uptake, reduced lung clearance, improved therapeutic efficacy, and reduced systemic side effects. The present study aimed to develop NAR-loaded PLGA nanoparticles (NAR PLGA NP) for enhanced cell-targeting in inflammatory lung conditions. NAR PLGA NP were prepared using the emulsion solvent evaporation method, with PLGA in the organic phase and soya lecithin (SL) with poly(vinyl alcohol) (PVA) as surfactants in the aqueous phase. A face-centered central composite design was employed to optimize the formulation. The optimized nanoparticles were characterized for size distribution by dynamic light scattering, entrapment efficiency, Transmission Electron Microscopy (TEM), Fourier Transform Infrared (FTIR), Differential Scanning Calorimetry (DSC), X-Ray Diffraction (XRD), and in vitro drug release. The safety of PLGA and lecithin-coated PLGA nanoparticles (LC PLGA NP) was assessed using an MTT assay on lung epithelial cells, followed by cellular uptake studies, angiogenesis by chick Yolk Sac Membrane (YSM) assay, and in vitro evaluation of reactive oxidative stress (ROS) and anti-inflammatory activity. The optimized PLGA formulation showed a hydrodynamic diameter of 201 ± 1 nm with PDI 0.20 ± 0.03 and EE of 76.11 ± 2.1%, and 81.7 ± 4.9% drug release at 72 h, whereas LC PLGA NP showed a hydrodynamic diameter of 308 ± 3 nm, PDI of 0.21 ± 0.05, entrapment efficiency of 82.45 ± 4.8%, and 71.4 ± 3.2% drug release at 72 h. Both PLGA NP and LC PLGA NP demonstrated good cytocompatibility with lung epithelial cells, efficient cellular uptake, and a significant reduction in intracellular reactive oxygen species (ROS) levels (****