title: Controlled release formulation of tramadol hydrochloride using hydrophilic and hydrophobic matrix system.
abstract: The effect of concentration of hydrophilic (hydroxypropyl methylcellulose [HPMC]) and hydrophobic polymers (hydrogenated castor oil [HCO], ethylcellulose) on the release rate of tramadol was studied. Hydrophilic matrix tablets were prepared by wet granulation technique, while hydrophobic (wax) matrix tablets were prepared by melt granulation technique and in vitro dissolution studies were performed using United States Pharmacopeia (USP) apparatus type II. Hydrophobic matrix tablets resulted in sustained in vitro drug release (>20 hours) as compared with hydrophilic matrix tablets (<14 hours). The presence of ethylcellulose in either of the matrix systems prolonged the release rate of the drug. Tablets prepared by combination of hydrophilic and hydrophobic polymers failed to prolong the drug release beyond 12 hours. The effect of ethylcellulose coating (Surelease) and the presence of lactose and HPMC in the coating composition on the drug release was also investigated. Hydrophobic matrix tablets prepared using HCO were found to be best suited for modulating the delivery of the highly water-soluble drug, tramadol hydrochloride.
authors: Department of Novel Drug Delivery Systems, Zydus Research Centre, Sarkhej Bavala National Highway No 8A, Moraiya, Ahmedabad- 382 213, Gujarat, India. sandiptiwari@zyduscadila.com
authors: Sandip B
authors: SB
authors: Tiwari
authors: T Krishna
authors: TK
authors: Murthy
authors: M Raveendra
authors: MR
authors: Pai
authors: Pavak R
authors: PR
authors: Mehta
authors: Pasula B
authors: PB
authors: Chowdary
mesh_terms: D002626:Chemistry, Pharmaceutical; D003692:Delayed-Action Preparations / Q000737:chemistry*; D004339:Drug Compounding / Q000379:methods; D016503:Drug Delivery Systems; D004355:Drug Stability; D057927:Hydrophobic and Hydrophilic Interactions; D012995:Solubility; D014147:Tramadol / Q000737:chemistry*
chemical_list: D003692:Delayed-Action Preparations; D014147:Tramadol