title: Pineal hormone melatonin: solubilization studies in model aqueous gastrointestinal environments.
abstract: In view of the variable oral absorption, short biological half-life and extensive first pass metabolism of the pineal hormone melatonin, an investigation of its solubilization profile in modified aqueous media is described. Four readily available surfactants were examined with respect to their ability to enhance the solubility of melatonin under simulated physiological conditions. The most effective surfactant was found to be the sodium salt of dioctyl sulfosuccinate (DSS), which augmented the aqueous solubility of the hormone by 23%. This is attributed to a favourable stereoelectronic interaction between DSS and the nucleus of melatonin, which seems to be independent of the pH of the dissolution medium. A noteworthy synergistic effect in the aqueous solubilization of the hormone occurs when a 1:2 DSS-sodium dodecyl sulphate mixture is used.
authors.affiliation: Faculty of Pharmacy, Department of Pharmaceutical Technology, University of Athens, Panepistimioupoli-Zografou, 157 71 Athens, Greece. vlachou@pharm.uoa.gr
authors.forename: Marilena
authors.initials: M
authors.lastname: Vlachou
authors.forename: Aphrodite
authors.initials: A
authors.lastname: Eikosipentaki
authors.forename: Vassilios
authors.initials: V
authors.lastname: Xenogiorgis
mesh_terms: D002021:Buffers; D004143:Dioctyl Sulfosuccinic Acid / Q000737:chemistry; D041981:Gastrointestinal Tract / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008550:Melatonin / Q000737:chemistry*; D011136:Polysorbates / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D012995:Solubility; D013501:Surface-Active Agents / Q000737:chemistry; D013656:Taurocholic Acid / Q000737:chemistry; D014867:Water / Q000737:chemistry*
chemical_list: D002021:Buffers; D011136:Polysorbates; D013501:Surface-Active Agents; D014867:Water; D004143:Dioctyl Sulfosuccinic Acid; D012967:Sodium Dodecyl Sulfate; D013656:Taurocholic Acid; D008550:Melatonin