Optimizing levofloxacin delivery using nanoparticles: a strategy for improved bioavailability and targeted release

Nanoparticle-based drug delivery systems have emerged as a powerful strategy to enhance drug bioavailability and ensure targeted therapeutic release. Levofloxacin (LFX), a widely used broad-spectrum fluoroquinolone antibiotic, is limited by poor aqueous solubility, low oral bioavailability, and systemic side effects. This study investigates the formulation, characterization, and evaluation of levofloxacin-loaded nanoparticles aimed at improving its pharmacological performance. Various nanoparticle carriers, including polymeric nanoparticles, lipid-based nanocarriers, and inorganic nanoparticles, were explored for their ability to encapsulate LFX and improve its delivery. Key formulation parameters such as encapsulation efficiency, drug loading, in vitro release profile, and stability at 4°C, 25°C, and 40°C were assessed. The optimized formulations demonstrated acceptable stability and sustained drug release across the tested conditions. Biocompatibility studies revealed no significant cytotoxic effects, as confirmed by high cell viability percentages, indicating the safety of the nanoparticle systems. Furthermore, the nanoparticle-loaded formulations exhibited enhanced dissolution behavior and potent in vitro antimicrobial activity against both Gram-negative and Gram-positive bacteria (p<0.05). Pharmacokinetic studies revealed statistically significant improvements (p<0.05) in maximum plasma concentration (Cmax), elimination half-life (t1/2), and area under the curve (AUC) compared to conventional formulations. In vivo evaluation using an infection model confirmed the superior antimicrobial efficacy of the nanoparticle-based system. The results collectively indicate that nanoparticle-based delivery of LFX substantially improves its bioavailability, pharmacokinetic profile, and therapeutic efficacy. These findings support the potential application of nanotechnology in overcoming the limitations of conventional LFX therapy and enhancing clinical outcomes in bacterial infection treatment. Keywords: Nanoparticle, Levofloxacin, Bioavailability, Encapsulation efficiency, Drug release kinetics