Effect of methyl cellulose on gelation behavior and drug release from poloxamer based ophthalmic formulations

The effect of weight average molecular weight (M-w) of methyl cellulose (MC) on the gelation behavior of Poloxamer 407 (PM) and in vitro release of Ketorolac Tromethamine (KT) from different ophthalmic formulations based on PM is examined. A drop of gelation temperature of PM is observed using MC of various M-w by test tube tilting method, UV-vis spectroscopy, viscometry and rheometry. It is also observed that the viscosity and gel strength of all the formulations are increased with the increase in M-w of MC. PM with highest M-w of MC provides best drug release property among all the formulations. It is evident from this investigation that there is a distinct effect of M-w of MC on the gelation behavior of PM as well as on the drug release profile of KT from PM-MC based ophthalmic formulations. (C) 2014 Elsevier B.V. All rights reserved.