Design and in vitro evaluation of polymer nanoparticle formulations containing norfloxacin for ocular application

Insufficient treatment of ocular infections can result in severe complications, including irreversible vision loss. Bacterial conjunctivitis, a highly prevalent ocular infection globally, is commonly managed with a variety of antibiotic therapies. Among these antibiotics, Norfloxacin (NFX) - a broad-spectrum fluoroquinolone - exhibits potent activity against both Gram-positive and Gram-negative bacterial pathogens, with its efficacy in ocular infections well-documented in the literature. Nonetheless, the therapeutic potential of NFX is significantly limited by its poor aqueous solubility and the anatomical structure and physiological barriers of the eye, leading to limited ocular bioavailability. To overcome these challenges, nanoparticles were formulated for sustained ocular drug delivery using Eudragit® RS 100 (ERS) alone and in combination with Polycaprolactone (PCL). Polymeric nanoparticles were prepared with spray-drying method and physicochemical characterization studies were performed in detail. The release kinetics were evaluated through in vitro dissolution studies, aiming to enhance the ocular bioavailability and therapeutic performance of NFX with the help of polymeric nanoparticles.