Original Articles
Hanan M. El-Laithy, Demiana I.
Abstract
This work describes the formulation of ophthalmic delivery systems of Moxifloxacin (Mox), as a model drug of fourth fluoroquinolone generation. Seven formulations (P1-P7) based on the concept of temperature triggered in situ gelation using pluronic (PL), and nine formulations (C1-C9) based on pH triggered in situ gelation using carbopol 934 (CL), were prepared. The developed formulae were evaluated regarding their gelation temperature (for PL systems), gelling capacity (for CL systems), rheological characteristics, in vitro release behavior and mucoadhesion measurements. Among different formulae tested, P6 and C5 showed optimum gelation temperature of 33.9 °C after dilution with simulated tear fluid (STF) and immediate gellation that remains for few hours respectively. Although the measured mucoadhesion index was higher (7.325 Pa) for C5 compared to (1.947 Pa) for P6, higher amount of Mox was retained in the aqueous humor area over 8 h following instillation of P6 with significant 2.8 fold increase in the Cmax and AUC(0-∞) compared to C5. Therefore, PL in situ gelling system can be used to enhance the ocular bioavailability more readily than CL system.