title: Analysis of rare flavonoid C-glycosides in Celtis australis L. by micellar electrokinetic chromatography.
abstract: This manuscript reports on the first analytical procedure for the determination of flavonoids in Celtis australis. The capillary electrophoretic separation of 8 compounds, most of them flavone C-glycosides, was possible using a borax buffer with pH 9.0, which contained 25mM SDS as detergent and 7.5% of n-butanol as organic modifier. Method validation revealed that the developed assay is repeatable (sigma(rel)<or=4.0%), precise (inter-day sigma(rel)<or=6.7%, intra-day sigma(rel)</=3.9%), accurate (recovery rates from 96.8 to 102.3%), sensitive (LOD: 2.2-1.6microg/ml) and linear (R(2)>or=0.9996) within the tested concentration range. The quantitative analysis of several C. australis samples showed that isovitexin is the most abundant representative (0.06-0.09%), at a rather uniform content of total flavonoids of approx. 0.3% in all specimens.
authors.affiliation: Institute of Pharmacy, Pharmacognosy, University of Innsbruck, Innrain 52, 6020 Innsbruck, Austria.
authors.forename: Nina
authors.initials: N
authors.lastname: Zehrmann
authors.forename: Christian
authors.initials: C
authors.lastname: Zidorn
authors.forename: Markus
authors.initials: M
authors.lastname: Ganzera
mesh_terms: D002021:Buffers; D020374:Chromatography, Micellar Electrokinetic Capillary; D005419:Flavonoids / Q000032:analysis*; D006027:Glycosides; D006863:Hydrogen-Ion Concentration; D009005:Monosaccharides / Q000032:analysis*; D018515:Plant Leaves; D015203:Reproducibility of Results; D034401:Ulmaceae / Q000737:chemistry*
chemical_list: D002021:Buffers; C438934:C-glycoside; D005419:Flavonoids; D006027:Glycosides; D009005:Monosaccharides