title: Effect of gliclazide immobilization into layered double hydroxide on drug release.
abstract: This paper deals with a new hydrotalcite-like compound used as a matrix to improve dissolution rate of the poorly water-soluble drug gliclazide and to administer at the same time micro- and oligo-elements useful to improve insulin performance. Gliclazide is a second-generation sulfonylurea compound used in the treatment of type II diabetes mellitus. As a consequence of the poor water solubility, its absorption is limited. Thus, a new hydrotalcite-like compound containing Zinc and Chromium, micronutrients directly involved in the physiology of insulin and in the carbohydrate, lipid and protein metabolism, was synthesized. The gliclazide-hydrotalcite-like clay nanohybrid was prepared via ion-exchange in its nitrate form and was characterized by inductively coupled plasma-optical emission spectrometry and thermogravimetric analysis. The drug loading resulted in 42.9% (w/w). As a consequence of the intercalation, the interlayer distance of the host increased from 0.89 nm (interlayer distance of nitrate form) to 1.5 nm. The intercalation product was submitted to solubility measurements and in vitro dissolution test. A remarkable improvement of the apparent solubility and dissolution rate in comparison to the crystalline drug was observed in acid fluids (pH 1.2 and 3). The presence of chromium and zinc cations was also found in the medium. These results showed that the hybrid nanostructure could represent a promising system to improve drug dissolution rate and to release cations involved in the performance of insulin.
authors.affiliation: Department of Pharmaceutical and Chemical Technology, University of Perugia, Perugia 06123, Italy. valeria.ambrogi@unipg.it
authors.forename: V
authors.initials: V
authors.lastname: Ambrogi
authors.forename: L
authors.initials: L
authors.lastname: Perioli
authors.forename: V
authors.initials: V
authors.lastname: Ciarnelli
authors.forename: M
authors.initials: M
authors.lastname: Nocchetti
authors.forename: C
authors.initials: C
authors.lastname: Rossi
mesh_terms: D000536:Aluminum Hydroxide / Q000737:chemistry*; D002626:Chemistry, Pharmaceutical; D002857:Chromium / Q000737:chemistry; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D004339:Drug Compounding; D005240:Feasibility Studies; D005907:Gliclazide / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007004:Hypoglycemic Agents / Q000737:chemistry*; D007700:Kinetics; D008276:Magnesium Hydroxide / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D053758:Nanoparticles; D012995:Solubility; D013054:Spectrophotometry, Atomic; D013818:Thermogravimetry; D015032:Zinc / Q000737:chemistry
chemical_list: D003692:Delayed-Action Preparations; D004337:Drug Carriers; D007004:Hypoglycemic Agents; D002857:Chromium; C010467:hydrotalcite; D000536:Aluminum Hydroxide; D005907:Gliclazide; D015032:Zinc; D008276:Magnesium Hydroxide