Feasibility of an in vitro microbiological model as an alternative to the rabbit eye model

Ocular inserts of gentamicin sulfate with polyvinyl alcohol (PVA) 1.5%, 2.0 %, and 2.5% and a combination of methyl cellulose 2% and Eudragit NE 30D 30 %, 35%, and 40% w/w of methyl cellulose were fabricated by a casting techni que. The inserts were sterilized by gamma radiation at 25 kGy and tested fo r sterility. The microbiological efficacy of the ocular inserts against Sta phylococcus aureus ATCC 6538P and Pseudomonas aeruginosa NCIM 2200 was eval uated by developing an in vitro microbiological model and an in vivo noninv asive rabbit eye model. Parameters of the in vitro microbiological model we re varied, and the results correlated with a noninvasive rabbit eye model. The in vitro model proved to be a viable alternative to the rabbit eye mode l in evaluating the microbiological efficacy of gentamicin sulfate ocular i nserts.