Effect of D-sorbitol on the thermal gelation of methylcellulose formulations for drug delivery.

The aim of this study was to examine the effect of D-sorbitol on the gelation characteristics of methylcellulose in aqueous solution. The addition of D-sorbitol at concentrations of between 25 and 30% (w/v) to 1.0-2.0% (w/v) methylcellulose solutions reduced the gelation temperature from approximately 53 degrees Celsius to values between ambient and 37 degrees Celsius and increased the strength of the gel. The in vitro release of acetaminophen (paracetamol) from 2.0% (w/v) methylcellulose gels containing 20-30% (w/v) D-sorbitol gel was diffusion-controlled.