Preparation and evaluation of oral enteric sustained-release liquid formulations of aspirin

Aim To develop an enteric sustained-release nanoparticle formulations of aspirin for applicability to a broader population.Methods Aspirin-loaded nanoparticles were prepared using poly(lactic-co-glycolic acid) (PLGA) and the enteric polymer Eudragit L100–55 through an optimized oil-in-water emulsification solvent evaporation method. The nanoparticles were subjected to comprehensive physicochemical characterization, including particle size, zeta potential, and morphological analysis. Additionally, their stability, in vitro drug release profile, cytotoxicity, intestinal absorption, and in vivo pharmacokinetics were systematically evaluated.Results The nanoparticles exhibited well-defined spherical morphology, uniform particle size, and favorable surface charge, demonstrating excellent biocompatibility. In the in vitro drug release study, AS-PLGA@NPs exhibited pronounced enterolysis effect. The morphology of the nanoparticles was confirmed by scanning electron microscopy (SEM) at different release stages. In vivo intestinal absorption and pharmacokinetic studies in rats demonstrated that AS-PLGA-EL@NPs enhanced drug absorption, prolonged drug release, and showed higher bioavailability compared to conventional enteric-coated tablets.Conclusion The development and preparation of an oral enteric sustained-release nanoparticle delivery system for aspirin has the potential to serve a broader population, with promising applications in various therapeutic contexts.