Application of in Situ Gelling Nanofibers for Ocular Drug Delivery Systems

Ocular drug delivery faces significant challenges in passing active substances through biological barriers. Ocular infections, driven by climate and lifestyle factors, are among the most common eye diseases globally. In the Middle East, fungal keratitis is prevalent due to poor air quality, while in developed countries, contact lens use is a major source of infections. A key obstacle in treating these infections is the low bioavailability of drugs, as tear fluid rapidly eliminates most medication within seconds, often leaving no trace in the eye after a few minutes. In situ gelling nanofiber systems offer a promising solution by absorbing eye moisture to form a gel, which increases viscosity and minimizes drug clearance due to eyelid movement. In this study, various nanofibers made of Pullulan and Gellan Gum (GG) are produced employing single-needle electrospinning. The nanofibers were labeled with fluorescein dye to determine drug residence time. Nanofiber morphology was examined via a Zeiss LV-SEM (۰.۵–۱.۰ kV) without sputter coating. Data were analyzed statistically in SPSS (v۲۹.۰.۱.۱). Two-way ANOVA with Tukey post-hoc analysis showed that all nanofiber samples remained stable until the third clearance cycle, while approximately ۸۰% of active drugs cleared with traditional eye drops. Modeling indicated that pure Pullulan nanofibers followed first-order removal kinetics, while Pullulan/GG nanofibers showed zero-order kinetics due to GG’s gelling in tear fluid. These in situ gelling nanofibers may reduce drug dosage and administration frequency.

کلیدواژه ها:

Ocular drug delivery ، in situ gelling nanofibers ، biological barriers ، Pullulan ، Gellan Gum ، eye infections