Main Article Content
of drugs, independent of pH and hydrodynamic conditions of gastrointestinal tract (GIT). The present study was
aimed to develop osmotic controlled extended release formulations of verapamil hydrochloride an angiotensin II receptor antagonist with antiâ€‘hypertensive activity. Verapamil hydrochloride matrix tablets were prepared by direct compression process using hydroxypropyl methylcellulose (HPMC) K 15M as polymeric material and mannitol as osmogen at varied concentrations. The matrix tablets were further coated with different compositions of ethylcellulose7cps and polyethylene glycol (PEG)â€‘4000 by pan coating method. Physical parameters such as weight uniformity, drug content, hardness and friability were evaluated for uncoated tablets and were found to be within I. P limits. The coating thickness and percentage
of coating applied for various tablets were also evaluated. The optimized coated tablets were further subjected to micro
drilling on the upper face to get 0.5 Âµm orifice diameter. All the tablets were further subjected to dissolution studies by
using USP apparatus II with 6.8 pH phosphate buffer as medium. These studies indicated that all the tablets were found to release the drug up to 12 hours, while coated tablets with orifice found to release the drug at zero order rate, which was
in good agreement with peppas n > 0.9.
Key words: Controlled release, micro drilling, osmotic pressure, verapamil hydrochloride
This is an Open Access article distributed under the terms of the Attribution-Noncommercial 4.0 International License [CC BY-NC 4.0], which requires that reusers give credit to the creator. It allows reusers to distribute, remix, adapt, and build upon the material in any medium or format, for noncommercial purposes only.
Thakor RS, Majmudar FD, Patel JK, Rajput GC. Osmotic drug delivery
systems current scenario. J Pharm Res 2010;34:771â€‘5.
Panchaxari MD, Navik VK, Anand P, Vinayak SM, Mayank MS. Oral osmotic
drug delivery system: An update. Int J Res Pharm Sci 2011;2:225â€‘36.
Gupta S, Ravindra PS, Rohitashva S, Renu K, Priyanka L. Osmotic pumps:
A review. Int J Clin Pharm 2011;6:1â€‘8.
Wakode R, Amrita B. Once a day osmotic drug delivery system for highly
water soluble Pramipexole. J Chem Pharm Res 2010;2:136â€‘46.
Theeuwes F, Swanson DR, Guittard G, Ayer A, Khanna S. Osmotic
delivery systems for the betaâ€‘adrenoceptor antagonists metoprolol
and oxprenolol: Design and evaluation of systems for onceâ€‘daily
administration. Br J Clin Pharm 1985;19:69â€‘76S.
Sean CS. The complete drug reference. 34th ed. London, England:
Pharmaceutical Press; 2011.
Hardy JG. Release rates from Sustainedâ€‘Release buccal tablets in man.
J Pharm Pharmacol 1982;34:91â€‘5.
Hogan JE. Hydroxy propyl methyl cellulose sustained release technology.
Drug Dev Ind Pharm 1989;15:975â€‘99.
Shah AC. Gelâ€‘matrix systems exhibiting bimodal controlled release for
oral delivery. J Control Release 1989;9:169â€‘75.
Wilson HC, Cuff GW. Sustained release of isomazole from matrix tablets
administered to dogs. J Pharm Sci 1989;78:582â€‘4.
Ozturk AG. Mechanism of release from pellets coated with an ethyl
celluloseâ€‘based film. J Control Release 1990;14:203â€‘13.
Narisawa S. Porosityâ€‘controlled ethyl cellulose film coating. IV.
Evaluation of mechanical strength of porous ethyl cellulose film. Chem
Pharm Bull 1994;42:1491â€‘5.
Debord B. Study of different crystalline forms of mannitol: Comparative
behaviour under compression. Drug Dev Ind Pharm 1987;13:1533â€‘46.
Molokhia AM. Aging of tablets prepared by direct compression of bases
with different moisture content. Drug Dev Ind Pharm 1987;13:1933â€‘46.
Lachman L, Lieberman HA, Kanig JL. The theory and practice of industrial
pharmacy. 3rd ed. Mumbai: Varghese Publishing House; 1987. p. 182â€‘4.
Herbert AL. Pharmaceutical Dosage Forms. Tablets 2005;2:321â€‘9.
Indian Pharmacopoeia. Government of India, Ghaziabad: The Indian