title: Formulation and evaluation of delayed-onset extended-release tablets of metoprolol tartrate using hydrophilic-swellable polymers.
abstract: In view of the circadian rhythm of cardiovascular diseases, a delayed-onset extended-release (DOER) formulation of metoprolol tartrate (MT) was prepared. This was achieved through dissolution-guided optimization of the proportion of Methocel K4M and Methocel K15M. Core erosion ratio was greater than 50 %, thereby showing steady release of the drug after the lag time until complete dissolution. Optimized formulation produced a lag phase of 6 h followed by complete release of 98.7 ± 2.1 % in 24 h. Water uptake study revealed that Methocel K15M has lower water uptake (30 ± 1 %) than Methocel K4M (40 ± 2 %) after 24 h. Axial swelling of polymers was higher than swelling in the radial direction. Drug-polymer interaction study precludes any interaction between drug and polymer. Such a drug delivery system may provide a viable alternative for effective management of hypertension and other related disorders. This work also proposes an approach to attain DOER for a hydrophilic drug by using a hydrophilic swellable polymer in press coat.
authors.affiliation: Delhi Institute of Pharmaceutical Sciences and Research, University of Delhi, New Delhi, India.
authors.forename: Subhash Chand
authors.initials: SC
authors.lastname: Dadarwal
authors.forename: Sarika
authors.initials: S
authors.lastname: Madan
authors.forename: Shyam Sunder
authors.initials: SS
authors.lastname: Agrawal
mesh_terms: D000319:Adrenergic beta-Antagonists / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D004339:Drug Compounding; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D008747:Methylcellulose / Q000737:chemistry*; D008790:Metoprolol / Q000737:chemistry*; D012995:Solubility; D013607:Tablets; D013678:Technology, Pharmaceutical / Q000379:methods; D014867:Water / Q000737:chemistry
chemical_list: D000319:Adrenergic beta-Antagonists; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D013607:Tablets; D014867:Water; D008747:Methylcellulose; D008790:Metoprolol