Application of Mathematical Models in Drug Release Kinetics of Carbidopa and Levodopa ER Tablets

The aim of present work is to determine and analyse the kinetics of drug release from the matrix tablet by employing various mathematical models. A study was done with Carbidopa and Levodopa ER tablets, 50 mg/200 mg by employing wet granulation technique using Hydroxypropyl methylcellulose and Hydroxypropyl cellulose as matrix forming polymer. The in-vitro drug release profile was carried out in 0.1 N HCl (900 mL) using USP dissolution apparatus II (Paddle) at 50 rpm at an extended time period of 0.5, 0.75, 1, 1.5, 2, 2.5, 3 and 4 hours. The drug release data was obtained, quantitatively correlated and interpreted with various mathematical models viz. Zero order model, first order model, Higuchi model, Hixson-Crowell model and Korsmeyer-Peppas model and evaluated to understand the kinetics of drug release. The criterion for the most suitable model was based on the high degree of coefficient of correlation of drug release profile of Carbidopa Levodopa ER Tablet. Hence, finally concluded as the drug release pattern of Carbidopa Levodopa ER Tablets, 50 mg/200 mg was best fitted with Higuchi square root model and follows Higuchi drug release kinetics which is diffusion controlled.