title: Robust and versatile pectin-based drug delivery systems.
abstract: Pectin-based resistant, interactive and versatile hydrogel vehicles for oral administration have been prepared. These systems are thought to be versatile enough to allow the inclusion of substances (such as the surfactants tested: Pluronic, Tween, Na Lauryl sulphate) that may contribute to tailor the drug release patterns. Tolbutamide, that shows a discrete and pH-dependent solubility in water, has been employed as a model drug to test the capability of these matrices to overcome such drug-imposed restraints. The incorporation of different surfactants produced pectin-based hydrogels of difficult manipulation. In order to improve this drawback, two different strategies have been developed: blending with agarose or freeze-drying. The presence of agarose yields robust systems that can be handled and tested as prepared, in the fresh state. Freeze-drying not only allows to shape pure pectin and blend systems, but also generates a porous structure whose microstructure, determined by the different components included, influences on the drug release behavior. Tolbutamide release kinetics from freshly prepared matrices can be fitted to the Higuchi model while the freeze-dried ones adjust to the Korsmeyer-Peppas model; hence the hydrogel chains rearrangement processes rule the release during the rehydration process.
authors.affiliation: Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040 Madrid, Spain. Electronic address: tmarrasm@ucm.es.
authors.forename: T
authors.initials: T
authors.lastname: Marras-Marquez
authors.affiliation: Departamento de Química Inorgánica y Bioinorgánica, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040 Madrid, Spain. Electronic address: juanpena@ucm.es.
authors.forename: J
authors.initials: J
authors.lastname: Peña
authors.affiliation: Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza Ramón y Cajal s/n, 28040 Madrid, Spain. Electronic address: mdveiga@ucm.es.
authors.forename: M D
authors.initials: MD
authors.lastname: Veiga-Ochoa
mesh_terms: D002626:Chemistry, Pharmaceutical; D004339:Drug Compounding / Q000379:methods; D016503:Drug Delivery Systems; D065546:Drug Liberation; D005612:Freeze Drying; D020100:Hydrogels; D006863:Hydrogen-Ion Concentration; D010368:Pectins / Q000737:chemistry*; D020442:Poloxamer / Q000737:chemistry; D011136:Polysorbates / Q000737:chemistry; D012685:Sepharose / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D012995:Solubility; D013501:Surface-Active Agents / Q000737:chemistry*; D014044:Tolbutamide / Q000008:administration & dosage* / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D020100:Hydrogels; D011136:Polysorbates; D013501:Surface-Active Agents; D014867:Water; D020442:Poloxamer; D012967:Sodium Dodecyl Sulfate; D010368:Pectins; D012685:Sepharose; D014044:Tolbutamide
keywords: Freeze-drying; Hydrogels; Kinetics; Oral drug delivery; Pore architecture; Surfactants