title: Drug release from E chemistry hypromellose tablets using the Bio-Dis USP type III apparatus: An evaluation of the effect of systematic agitation and ionic strength.
abstract: The aim of the study was to evaluate the effect of systematic agitation, increasing ionic strength and gel strength on drug release from a gel-forming matrix (HPMC E10M, E4M and E50LV) using USP type III Bio-Dis apparatus with theophylline as a model drug. The triboelectric charging; particle sizing, water content, true density and SEM of all the hypromellose grades, theophylline and formulated blends were characterised. The results showed that balanced inter-particulate forces exist between drug particles and the excipient surface and this enabled optimum charge to mass ratio to be measured. Agitation and ionic strength affected drug release from E50LV and E4M tablet matrices in comparison to the E10M tablet matrices. Drug release increased substantially when water was used as the dissolution media relative to media at pH 1.2 (containing 0.4M NaCl). The results showed all f2 values for the E10M tablet matrices were above 50 suggesting the drug release from these tablet matrices to be similar. Rheological data also explained the different drug release behaviour with the stress required to yield/erode being 1Pa, 150Pa, and 320Pa, for the E50LV, E4M and E10M respectively. The stiffness of the gel was also found to be varied from 2.5Pa, 176.2Pa and 408.3Pa for the E50LV, E4M and E10M respectively. The lower G' value can be explained by a softer gel being formed after tablet introduction into the dissolution media thereby indicating faster drug release.
authors.affiliation: Department of Pharmacy, University of Huddersfield, Huddersfield HD1 3DH, UK. Electronic address: k.asare-addo@hud.ac.uk.
authors.forename: Kofi
authors.initials: K
authors.lastname: Asare-Addo
authors.affiliation: Department of Chemical Sciences, University of Huddersfield, Huddersfield HD1 3DH, UK.
authors.forename: Enes
authors.initials: E
authors.lastname: Supuk
authors.affiliation: Department of Pharmacy, University of Huddersfield, Huddersfield HD1 3DH, UK.
authors.forename: Mohammed H
authors.initials: MH
authors.lastname: Mahdi
authors.affiliation: Department of Pharmacy, University of Huddersfield, Huddersfield HD1 3DH, UK.
authors.forename: Adeola O
authors.initials: AO
authors.lastname: Adebisi
authors.affiliation: Department of Pharmaceutics and Pharmaceutical Technology, Faculty of Pharmaceutical Science, University of Jos, PMB 2084, Jos 930001, Nigeria.
authors.forename: Elijah
authors.initials: E
authors.lastname: Nep
authors.affiliation: Department of Pharmacy, University of Huddersfield, Huddersfield HD1 3DH, UK.
authors.forename: Barbara R
authors.initials: BR
authors.lastname: Conway
authors.affiliation: School of Pharmacy, University of Wolverhampton, Faculty of Science and Engineering, Wolverhampton WV1 1LY, UK.
authors.forename: Waseem
authors.initials: W
authors.lastname: Kaialy
authors.affiliation: Chemistry and Drug Delivery group, Medway School of Pharmacy, University of Kent, Chatham, Kent ME4 4TB, UK.
authors.forename: Hiba
authors.initials: H
authors.lastname: Al-Hamidi
authors.affiliation: School of Life Sciences, University of Sussex, JMS Building, Falmer, Brighton, UK; Drug Applied Research Centre and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran.
authors.forename: Ali
authors.initials: A
authors.lastname: Nokhodchi
mesh_terms: D057205:Automation, Laboratory; D004339:Drug Compounding; D065546:Drug Liberation; D005782:Gels; D006863:Hydrogen-Ion Concentration; D065347:Hypromellose Derivatives / Q000737:chemistry*; D007700:Kinetics; D009994:Osmolar Concentration; D012399:Rotation; D013607:Tablets; D013806:Theophylline / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D005782:Gels; D013607:Tablets; D014867:Water; D065347:Hypromellose Derivatives; D013806:Theophylline
keywords: Agitation sequence; HPMC polymeric matrix tablets triboelectrification; Ionic concentration strength; Rheology; USP III apparatus