Delivering an effective drug load to the posterior section of the ocular tissues, while using a\nnon-invasive technique, has always been a challenge. In this regard, the goal of the present study was\nto develop sustained release triamcinolone acetonide (TA) loaded polymeric matrix films for ocular\ndelivery. The TA-films were prepared in two different polymer matrices, with drug loadings of 10%\nand 20% w/w, and they were evaluated for ocular distribution in vivo in a conscious rabbit model.\nA 4%w/v TA suspension (TA-C) was used as a control for in vitro and in vivo studies. The TA-films,\nprepared with melt-cast technology, used polyethylene oxide (PEO) and Soluplus® as the polymer\nmatrix. The films were evaluated with respect to assay, content uniformity, excipient interaction, and\npermeability across isolated rabbit sclera. The distribution of TA in the ocular tissues, post topical\nadministration, was determined in New Zealand male albino rabbits as a function of dose, and was\ncompared against TA-C. The assay of the 10% and 20% w/w film was in the range from 70â??79% and\n92â??94% for the Soluplus® and PEO films, respectively, and content uniformity was in the range of\n95â??103% for both the films. The assay of the TA from Soluplus® films was less compared with the\nPEO films and showed an interaction with TA, as revealed by Differential Scanning Calorimetry\n(DSC). Hence, Soluplus® films were not selected for further studies. No interaction was observed\nbetween the drug and PEO polymer matrix. The enhancement of trans-scleral flux and permeability\nof TA was about 1.16 and 1.33-folds, respectively, from the 10% w/w PEO and 3.5 and 2.12-folds,\nrespectively, from the 20% w/w PEO films, as compared with TA-C formulations. The in vivo studies\ndemonstrate that significantly higher TA levels were observed in the anterior and posterior segments\nof the eye at the end of 6h with the PEO films. Therefore, the PEO based polymeric films were able to\ndeliver TA into the back of the eye efficiently and for prolonged periods.
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