Formulation and Evaluation of Niosomal In-Situ Gel for Ophthalmic Use

Conventional liquid ophthalmic formulations are most convenient from patient point of view. But these formulation shows low bioavailability because of a constant lachrymal drainage in the eye which leads to frequent dosing. Moreover, the absorption of the drug drained through the nasolacrymal duct may result in undesirable side effects. To overcome these limitation different approaches has been applied such as ointment, gel, cream etc. These ophthalmic formulations also fails to show desired therapeutic responses because of their own disadvantages such as ointment makes blurred vision. So two different systems was combined together as niosomes and in-situ gel by incorporating niosomes in in-situ gel formulation so that it is easy to administered and retain at the site for prolong period of time. The Ofloxacin (OFL), a second generation fluoroquinolone derivative used in eye infections needs frequent dosing in its solution form. Vesicular system reported prolonged and controlled action at corneal surface but it has again limitation of drainage along tear produced.  In this, first niosomes containing ofloxacin were prepared by applying 32 full factorial designs and evaluated for its vesicle size, percent entrapment, in-vitro drug release kinetics and their stability. Also in-situ gel formulation was prepared by dispersing the niosomes in solution of carbopol 940 and Hydroxy Propyl Methyl Cellulose (HPMC) K4M. In-vitro drug release kinetics from niosomal in-situ gel formulation indicates that the minimum inhibitory concentration (MIC) of drug (4 μg/ml) was achieved within 1-2 hrs (batch G1-G9).