2026-06-29T03:12:47Zhttps://docta.ucm.es/rest/oai/request

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00925njm 22002777a 4500 dc Vizcaya, David author Tirado, Diego F. author Cabañas Poveda, Albertina author Serrano López, Dolores Remedios author Calvo Garrido, María Lourdes author 2026-01 Breaking away from the limitations of conventional solvent evaporation (SE), supercritical fluid extraction of emulsions (SFEE) offers a transformative approach to the production of polymeric nanoparticles. In this study, both SFEE and SE were applied to formulate nanoparticles composed of Eudragit® S100 loaded with 5-aminosalicylic acid (5-ASA), a drug widely used in the treatment of inflammatory bowel disease (IBD). A comparison was made between the two methods in terms of particle size distribution, encapsulation efficiency, residual solvent content, and morphology. Formulation efforts focused on obtaining a stable emulsion. A mixed organic phase was required: acetone to dissolve the polymer and a second solvent to solubilise the drug, underscoring the formulation challenge. Among the solvents evaluated, dimethyl sulfoxide (DMSO) was selected due to its ability to maximise 5-ASA solubility, enhance emulsion stability, and its classification as a low-risk Class 3 solvent. SFEE resulted in larger particle sizes (D50 = 165 nm) and slightly lower encapsulation efficiency (EE = 84 %) compared to SE (D50 = 85 nm, EE = 99 %). Despite the high boiling point of DMSO, SFEE achieved a significant reduction in residual solvent content (< 4 %) versus 21 % in SE particles. Both particles showed similar release profiles, with a rapid release of 5-ASA under acidic conditions despite being formulated with a pH-sensitive polymer. This behaviour was likely attributed to the nanometric size and high surface area of the particles, which favoured rapid drug diffusion. David Vizcaya, Diego F. Tirado, Albertina Cabañas, Dolores R. Serrano, Lourdes Calvo, Preparation of 5-ASA-loaded Eudragit® S100 nanoparticles by emulsion-based methods: Comparison between solvent evaporation and supercritical fluid extraction, The Journal of Supercritical Fluids, Volume 227, 2026, 106753, ISSN 0896-8446 10.1016/j.supflu.2025.106753 https://hdl.handle.net/20.500.14352/133261 https://doi.org/10.1016/j.supflu.2025.106753 Preparation of 5-ASA-loaded Eudragit® S100 nanoparticles by emulsion-based methods: Comparison between solvent evaporation and supercritical fluid extraction