<i>In situ</i> fast gelling formulation of methyl cellulose for <i>in vitro</i> ophthalmic controlled delivery of ketorolac tromethamine

Abstract

Abstract The development of an in‐situ fast gelling vehicle for ophthalmic drug delivery based on methylcellulose (MC) was studied. The gelation temperature of 1 % MC was 59°C. Additives such as fructose and sodium citrate tribasic dihydrate (SC) were added in different proportions to reduce the gelation temperature of MC from 59°C to the physiological temperature i.e. 37°C. With the variation of fructose concentration from 2 to 10% at constant 1% MC concentration, the gel temperature was reduced from 59 to 54°C. To reduce the gelation temperature of MC further, SC was added in the system where the concentration of MC (1%) and fructose (10%) were kept constant. It was observed that with the variation of SC concentration from 1 to 5%, the sol–gel transition temperature was further lowered from 54 to 32°C. The gel temperature of all the combinations was measured by test tube tilting method and followed by UV–vis spectroscopy. The developed formulation corresponding to gelation temperature 32°C provided sustained release of Ketorolac Tromethamine (KT) over a 9 h period. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009