title: Selective reversed-phase liquid chromatography method for the kinetic investigation of 3-hydroxyflavone photostability.
abstract: This paper reports a fast and accurate RP-HPLC chromatographic method for the simultaneous determination of 3-hydroxyflavone (3-OH F) and its photodegradation products. Solutions (5 x 10(-5) M) in acetonitrile (ACN) of the molecule were subjected to forced degradation by exposure to artificial UV-A light source (black-light, lambda(max) 354 nm) and the changes appearing in chromatograms were monitored at selected irradiation times. A multistep gradient was optimised to achieve complete elution of all photoproducts in the shortest analysis time. UV spectra recorded by the diode array detector system (285 and 340 nm) clearly showed the structural changes in the new species formed, with respect to the parent compound. The analytical method was subjected to a validation procedure in which linearity and range, as well as specificity, precision and accuracy were determined according to ICH guidelines. Quantitative evaluation of the photochemical process was performed on the basis of the calculated kinetic parameters: photodegradation rate constant k, half-life time t(0.5), time degradation of 10% of the drug t(0.1).
authors.affiliation: Pharmaco-Chemical Department, Faculty of Pharmacy, University of Messina, Viale Annunziata, 98168 Messina, Italy.
authors.forename: M L
authors.initials: ML
authors.lastname: Calabrò
authors.forename: S
authors.initials: S
authors.lastname: Tommasini
authors.forename: D
authors.initials: D
authors.lastname: Raneri
authors.forename: P
authors.initials: P
authors.lastname: Donato
authors.forename: P
authors.initials: P
authors.lastname: Ficarra
authors.forename: R
authors.initials: R
authors.lastname: Ficarra
mesh_terms: D000465:Algorithms; D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D005419:Flavonoids / Q000737:chemistry*; D044948:Flavonols / Q000737:chemistry; D005456:Fluorescent Dyes / Q000737:chemistry*; D006207:Half-Life; D006860:Hydrogen Bonding; D007700:Kinetics; D008956:Models, Chemical; D010777:Photochemistry; D015203:Reproducibility of Results; D013056:Spectrophotometry, Ultraviolet; D014466:Ultraviolet Rays
chemical_list: D005419:Flavonoids; D044948:Flavonols; D005456:Fluorescent Dyes; C041477:3-hydroxyflavone