title: Formulation of bi-layer matrix tablets of tramadol hydrochloride: Comparison of rate retarding ability of the incorporated hydrophilic polymers.
abstract: Bi-layer tablets of tramadol hydrochloride were prepared by direct compression technique. Each tablet contains an instant release layer with a sustained release layer. The instant release layer was found to release the initial dose immediately within minutes. The instant release layer was combined with sustained release matrix made of varying quantity of Methocel K4M, Methocel K15MCR and Carbomer 974P. Bi-layer tablets were evaluated for various physical tests including weight variation, thickness and diameter, hardness and percent friability. Drug release from bi-layer tablet was studied in acidic medium and buffer medium for two and six hours respectively. Sustained release of tramadol hydrochloride was observed with a controlled fashion that was characteristic to the type and extent of polymer used. % Drug release from eight-hour dissolution study was fitted with several kinetic models. Mean dissolution time (MDT) and fractional dissolution values (T25%, T50% and T80%) were also calculated as well, to compare the retarding ability of the polymers. Methocel K15MCR was found to be the most effective in rate retardation of freely water-soluble tramadol hydrochloride compared to Methocel K4M and Capbomer 974P, when incorporated at equal ratio in the formulation.
authors.affiliation: Department of Pharmacy, University of Asia Pacific, Dhanmondi, Dhaka, Bangladesh.
authors.forename: Hasanul
authors.initials: H
authors.lastname: Arif
authors.affiliation: Research & Development Formulation Department, Incepta Pharmaceuticals Ltd., Savar, Dhaka, Bangladesh.
authors.forename: Abdullah
authors.initials: A
authors.lastname: Al-Masum
authors.affiliation: Department of Pharmacy, University of Asia Pacific, Dhanmondi, Dhaka, Bangladesh.
authors.forename: Florida
authors.initials: F
authors.lastname: Sharmin
authors.affiliation: Department of Pharmaceutical Technology, Faculty of Pharmacy, University of Dhaka, Dhaka, Bangladesh.
authors.forename: Selim
authors.initials: S
authors.lastname: Reza
authors.affiliation: Department of Pharmacy, University of Asia Pacific, Dhanmondi, Dhaka, Bangladesh.
authors.forename: Sm Ashraful
authors.initials: SA
authors.lastname: Sm Islam
mesh_terms: D000180:Acrylic Resins / Q000493:pharmacokinetics*; D000701:Analgesics, Opioid / Q000493:pharmacokinetics*; D003692:Delayed-Action Preparations / Q000737:chemistry / Q000493:pharmacokinetics; D004339:Drug Compounding; D006244:Hardness; D008747:Methylcellulose / Q000493:pharmacokinetics*; D013607:Tablets / Q000737:chemistry / Q000493:pharmacokinetics*; D014147:Tramadol / Q000493:pharmacokinetics*
chemical_list: D000180:Acrylic Resins; D000701:Analgesics, Opioid; D003692:Delayed-Action Preparations; D013607:Tablets; C479038:carbomer; D014147:Tramadol; D008747:Methylcellulose