Posted by The main aim of this study was to improve the solubility of dexamethason (DXM) with a CD derivative and increase the residence time by formulating an in situ gelling drug delivery system based on P407 in combination with other polymers.
The further aim was to evaluate the effect of the combination of hydroxypropyl-β-cyclodextrin (HPBCD), in situ gelling formulations, and other mucoadhesive polymers, i.e., hydroxypropyl methylcellulose (HPMC) and zinc-hyaluronate (ZnHA), on permeation by applying in vitro and ex vivo ophthalmic permeation models. Additionally, gelling properties, in vitro drug release, and mucoadhesion were measured to determine the impact of these factors on permeation and ultimately on bioavailability. The results showed that GEL1 and GEL2 had an optimal gelling temperature, 36.3 ℃ and 34.6 ℃, respectively. Moreover, the combination of Poloxamer 407 (P407) with other polymers improved the mucoadhesion (GEL1: 1333.7 mN) compared with formulations containing only P407 (P12: 721.8 mN). Both HPBCD and the gel matrix had a considerable influence on the drug release and permeability of DXM, and the combination could facilitate the permeation into the aqueous humor. After 30 min of treatment, the DXM concentration in the aqueous humor was 1.16–1.37 µg∕mL in case of the gels, whereas DXM could not be detected when treated with the DXM suspension.
Boglárka Szalai, Mária Budai-Szűcs, Anita Kovács, Szilvia Berkó, Ilona Gróf, Mária A. Deli, Gábor Katona, György T. Balogh, Orsolya Jójárt-Laczkovich (2024) The effect of mucoadhesive polymers on ocular permeation of thermoresponsive in situ gel containing dexamethasone–cyclodextrin complex. International Journal of Pharmaceutics 667, Part A, 124848. https://doi.org/10.1016/j.ijpharm.2024.124848.