Creation and Assessment of an Ocular Film Based on Solid Lipid Nanoparticles of Fluconazole for the Treatment of Fungal Infection

This work focuses on the integration of the lipophilic medication fluconazole into solid lipids, particularly stearic acid, and stabilized with Tween 80. Two approaches, namely the microemulsion method and ultrasonication, were evaluated for producing fluconazole-loaded solid lipid nanoparticles (SLNs). The formulation included Carbopol 934, which facilitates controlled drug release. It was found that higher concentrations of Carbopol 934 enhanced the sustained release of the drug by creating robust matrices due to its cross-linked nature. Particle size analysis revealed that the SLNs maintained an ideal size of less than 400 nm, exhibited a favorable polydispersity index (PDI), and displayed a negative zeta potential, all of which contribute to a longer precorneal residence time. Ultrasound-produced nanoparticles (FUSLN-4) significantly improved drug delivery to the cornea. X-ray diffraction and calorimetry confirmed reduced drug crystallinity within these nanoparticles, leading to enhanced drug release (up to 12 hours) and corneal penetration. Importantly, this method maintained corneal moisture. FUSLN-4 outperformed a microemulsion formulation and showed excellent stability (two years at room temperature), offering a promising solution to the challenges of ophthalmic drug delivery.