title: Supercritical fluid extraction of isoflavones from biological samples with ultra-fast high-performance liquid chromatography/mass spectrometry.
abstract: An efficient method of modifier addition for supercritical fluid extraction (SFE) of polar isoflavones was developed and yielded extraordinarily high recoveries. To find the optimal extraction conditions, a temperature and pressure optimization and modifier impact study was performed in naturally contaminated and spiked samples. Ultra-fast high-performance liquid chromatography/mass spectrometry (HPLC/MS) was used for the determination of isoflavones on an Atlantis dC18 high-speed reversed phase chromatographic column (20 x 2.1 mm, 3 microm particle size). A newly elaborated supercritical fluid extraction (SFE) procedure allowed more accurate (< 5%) and precise (< 4-7%) determination of isoflavones in biological materials. The HPLC/MS method significantly reduced analysis time with simultaneous improvement of sensitivity and detection limits. The on-column limits of detection LOD (S/N = 3) for isoflavone glycosides (daidzin, genistin, glycitin, ononin, and sissotrin) were 1.3-3.6 fmol and 0.2-1.0 fmol for aglycones (daidzein, glycitein, genistein, formononetin, and biochanin A), respectively.
authors.affiliation: Department of Chemistry and Biochemistry, Mendel University of Agriculture and Forestry, Brno, Czech Republic.
authors.forename: Borivoj
authors.initials: B
authors.lastname: Klejdus
authors.forename: Lea
authors.initials: L
authors.lastname: Lojková
authors.forename: Oldrich
authors.initials: O
authors.lastname: Lapcík
authors.forename: Radka
authors.initials: R
authors.lastname: Koblovská
authors.forename: Jitka
authors.initials: J
authors.lastname: Moravcová
authors.forename: Vlastimil
authors.initials: V
authors.lastname: Kubán
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005504:Food Analysis / Q000379:methods; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification; D007529:Isoflavones / Q000737:chemistry / Q000302:isolation & purification*; D013058:Mass Spectrometry / Q000379:methods*; D013025:Glycine max / Q000737:chemistry; D029921:Trifolium / Q000737:chemistry
chemical_list: D006027:Glycosides; D007529:Isoflavones