title: Solubilization of flavopiridol by pH control combined with cosolvents, surfactants, or complexants.
abstract: This study investigates the roles of both ionized and un-ionized species of flavopiridol in solubilization by complexation, micellization, and cosolvency. Control of pH was used in combination with surfactants (polysorbate 20 and polysorbate 80), cosolvents (ethanol and propylene glycol), as well as uncharged and anionic complexing agents [hydroxypropyl beta-cyclodextrin (HPbetaCD) and sulfobutyl ether beta-cyclodextrin (SBEbetaCD)] to solubilize flavopiridol. These combined techniques increase not only the solubility of the un-ionized flavopiridol but also the solubility of the ionized drug. This study confirms that previously developed equations effectively characterize the roles of pH, pK(a), and either complexation constant, micelle partition coefficient, or cosolvent solubilizing power in determining drug total aqueous solubility.
authors.affiliation: Department of Pharmaceutical Sciences, College of Pharmacy, University of Arizona, Tucson, Arizona 85721, USA.
authors.forename: P
authors.initials: P
authors.lastname: Li
authors.forename: S E
authors.initials: SE
authors.lastname: Tabibi
authors.forename: S H
authors.initials: SH
authors.lastname: Yalkowsky
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D005079:Excipients; D005419:Flavonoids / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D010880:Piperidines / Q000737:chemistry*; D012995:Solubility; D012997:Solvents; D013501:Surface-Active Agents
chemical_list: D000970:Antineoplastic Agents; D005079:Excipients; D005419:Flavonoids; D008823:Micelles; D010880:Piperidines; D012997:Solvents; D013501:Surface-Active Agents; C077990:alvocidib