Formulation Development and Evaluation of Bilayer Tablets Containing Paracetamol SR and Tizanidine
Journal of Applied Pharmacy
In the present study Paracetamol and Tizanidine were considered as the model drugs for development of bilayer tablets. Paracetamol with the dose 600mg/tablet was considered under the matrix layer and Tizanidine with the dose 2mg/tablet was considered under immediate release layer. The polymers like HPMC (Hydroxy propyl methyl cellulose) K100 & K4 grades, guar gum are used for development of matrix layer. The calibration curve for Paracetamol was plotted by using UV spectroscope at an absorbance
... pe at an absorbance of 280 nm as per the method developed by glenmak pharmaceutical ltd. The calibration curve for Tizanidine was plotted by using HPLC at an absorbance of 230nm. The physicochemical parameters of both the matrix tablets of Paracetamol as well as bilayer tablets were carried out. The formulation of sustained release layer was optimized with respect to their dissolution parameters. The dissolution of the bilayer tablets were carried out in 0.1N HCl. The optimized batches showing a release rate more than 90% were considered for development of bilayer tablets. The pharmacokinetic parameters for both the matrix layer formulations of Paracetamol as well as bilayer tablets were conducted with zero order, first order, higuchi and korsemeyer patterns. The optimized formulations were found to be following zero order release kinetics. The accelerated stability study of the optimized formulations (matrix layer and bilayer tablets) were conducted for three months at the conditions of 40 o c/75%RH and found to be stable. The FTIR study was conducted for determining drug polymer interaction.