title: Prolonged intragastric drug delivery mediated by Eudragit® E-carrageenan polyelectrolyte matrix tablets.
abstract: Interpolyelectrolyte (IPE) complexation between carrageenan (CG) and Eudragit E (EE) was studied in 0.1 M HCl and was used to develop floating matrix tablets aimed to prolong gastric-residence time and sustain delivery of the loaded drug. The optimum EE/CG IPE complexation weight ratio (0.6) was determined in 0.1 M HCl using apparent viscosity measurements. The IPE complex was characterized by Fourier transform infrared spectroscopy and differential scanning calorimetry. Metronidazole matrix tablets were prepared by direct compression using EE, CG, or hybrid EE/CG with ratio optimal for IPE complexation. Corresponding effervescent tablets were prepared by including Na bicarbonate as an effervescent agent. Tablets were evaluated for in vitro buoyancy and drug release in 0.1 M HCl. Both CG and EE-CG effervescent matrices (1:2 drug to polymer weight ratio, 60 mg Na bicarbonate) achieved fast and prolonged floating with floating lag times less than 30 s and floating duration of more than 10 h. The corresponding EE effervescent matrices showed delayed floating and rapid drug release, and completely dissolved after 3 h of dissolution. CG matrices showed an initial burst drug release (48.3±5.0% at 1 h) followed by slow drug release over 8 h. EE-CG matrices exhibited sustained drug release in almost zero-order manner for 10 h (68.2±6.6%). The dissolution data of these matrices were fitted to different dissolution models. It was found that drug release followed zero-order kinetics and was controlled by the superposition of the diffusion and erosion.
authors.affiliation: Faculty of Pharmacy, University of Jordan, Amman, Jordan. abjaber@ju.edu.jo
authors.forename: Ahmad
authors.initials: A
authors.lastname: Bani-Jaber
authors.forename: Leena
authors.initials: L
authors.lastname: Al-Aani
authors.forename: Hatim
authors.initials: H
authors.lastname: Alkhatib
authors.forename: Bashar
authors.initials: B
authors.lastname: Al-Khalidi
mesh_terms: D000284:Administration, Oral; D000890:Anti-Infective Agents / Q000008:administration & dosage* / Q000737:chemistry; D002351:Carrageenan / Q000737:chemistry*; D003692:Delayed-Action Preparations; D004058:Diffusion; D004337:Drug Carriers; D004339:Drug Compounding; D016503:Drug Delivery Systems; D005079:Excipients; D006801:Humans; D008795:Metronidazole / Q000008:administration & dosage* / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011109:Polymethacrylic Acids / Q000737:chemistry*; D012995:Solubility; D013270:Stomach / Q000187:drug effects; D013272:Stomach Diseases / Q000188:drug therapy; D014783:Viscosity
chemical_list: D000890:Anti-Infective Agents; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D005079:Excipients; D011108:Polymers; D011109:Polymethacrylic Acids; D008795:Metronidazole; D002351:Carrageenan; C518398:Eudragit E PO