Development of celecoxib eye drop solution and microsuspension: A comparative investigation of binary and ternary cyclodextrin complexes.

The very low aqueous solubility of celecoxib (CCB) hampers its ocular bioavailability. Thus, the aim of this study was to develop topical eye drop formulations containing cyclodextrin (CD) and a biocompatible polymer in an aqueous microsuspension. Aqueous CCB eye drop formulations containing biocompatible carbohydrate nano- and microparticles were prepared and their physicochemical and mucoadhesive properties evaluated. In vitro and ex-vivo permeation studies were performed as well as retinal cell viability tests. The appearance of the eye drop formulations and their pH, osmolality and viscosity were within acceptable range. The formulations containing hyaluronic acid (HA), a natural polysaccharide found in the eye, displayed excellent mucoadhesive properties. An increasing CCB content of the eye drops, obtained by heating method (sonication at the temperature of 70 °C for 1 h) to form ternary CCB/CD/polymer complex, resulted in higher drug permeation through a semipermeable membrane, simulated artificial vitreous humor and scleral tissues, especially from the formulation containing randomly methylated βCD and HA (0.5% w/v). The CCB eye drops demonstrated no cytotoxicity in a human retina cell line.