title: Gamma scintigraphic study of the hydrodynamically balanced matrix tablets of Metformin HCl in rabbits.
abstract: The purpose of this study is to evaluate the in vitro and in vivo performance of gastro-retentive matrix tablets having Metformin HCl as model drug and combination of natural polymers. A total of 16 formulations were prepared by a wet granulation method using xanthan, tamarind seed powder, tamarind kernel powder and salep as the gel-forming agents and sodium bicarbonate as a gas-forming agent. All the formulations were evaluated for compendial and non-compendial tests and in vitro study was carried out on a USP-II dissolution apparatus at a paddle speed of 50 rpm. MOX2 formulation, composed of salep and xanthan in the ratio of 4:1 with 96.9% release, was considered as the optimum formulation with more than 90% release in 12 hours and short floating lag time. In vivo study was carried out using gamma scintigraphy in New Zealand White rabbits, optimized formulation was incorporated with 10 mg of (153)Sm for labeling MOX2 formulation. The radioactive samarium oxide was used as the marker to trace transit of the tablets in the gastrointestinal tract. The in vivo data also supported retention of MOX2 formulation in the gastric region for 12 hours and were different from the control formulation without a gas and gel forming agent. It was concluded that the prepared floating gastro-retentive matrix tablets had a sustained-release effect in vitro and in vivo, gamma scintigraphy played an important role in locating the oral transit and the drug-release pattern.
authors.affiliation: Department of Pharmacy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Mahboubeh
authors.initials: M
authors.lastname: Razavi
authors.affiliation: Department of Pharmacy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Hamed
authors.initials: H
authors.lastname: Karimian
authors.affiliation: Department of Biomedical Imaging and University of Malaya Research Imaging Centre, Faculty of Medicine, Kuala Lumpur, Malaysia.
authors.forename: Chai Hong
authors.initials: CH
authors.lastname: Yeong
authors.affiliation: Department of Biomedical Imaging and University of Malaya Research Imaging Centre, Faculty of Medicine, Kuala Lumpur, Malaysia.
authors.forename: Sazilah Ahmad
authors.initials: SA
authors.lastname: Sarji
authors.affiliation: Department of Pharmacy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Lip Yong
authors.initials: LY
authors.lastname: Chung
authors.affiliation: Department of Pharmacy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia ; Department of Chemistry, Centre for Natural Products and Drug Discovery (CENAR), Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Shaik
authors.initials: S
authors.lastname: Nyamathulla
authors.affiliation: Department of Pharmacy, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia ; Department of Chemistry, Centre for Natural Products and Drug Discovery (CENAR), Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
authors.forename: Mohamed Ibrahim
authors.initials: MI
authors.lastname: Noordin
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001682:Biological Availability; D002626:Chemistry, Pharmaceutical; D018360:Crystallography, X-Ray; D003692:Delayed-Action Preparations; D005079:Excipients / Q000737:chemistry*; D041981:Gastrointestinal Tract / Q000000981:diagnostic imaging*; D007004:Hypoglycemic Agents / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics*; D008297:Male; D008687:Metformin / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics*; D064847:Multimodal Imaging; D011108:Polymers / Q000737:chemistry*; D011135:Polysaccharides, Bacterial / Q000737:chemistry; D011817:Rabbits; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D013607:Tablets; D013678:Technology, Pharmaceutical / Q000379:methods*; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
chemical_list: D003692:Delayed-Action Preparations; D005079:Excipients; D007004:Hypoglycemic Agents; D011108:Polymers; D011135:Polysaccharides, Bacterial; D013607:Tablets; D008687:Metformin; C002563:xanthan gum
keywords: gamma scintigraphy; gastro-retentive drug delivery; natural polymer; salep; sustain release formulation; tamarind seed