ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Comparison of Solid-Phase Extraction Procedures for Isolation of Plant Isoflavones Prior to Liquid Chromatographic Determination

B. Klejdus, J. Třináctý, P. Hrdlička, and V. Kubáň

Department of Chemistry and Biochemistry, Mendel University of Agriculture and Forestry, CZ-613 00 Brno

E-mail: kuban@mendelu.cz

Abstract: Solid-phase extraction (SPE) procedures for isolation of isoflavones using five different SPE cartridges and subsequent RP-HPLC separation and quantitation of daidzein, genistein, formononetin, and biochanin A were compared. Extraction efficiencies were evaluated and recoveries greater than 91-99 % were obtained using the OASIS^TM HLB copolymer cartridges. The isoflavones extracted with a mixture of 80 vol. % ethanol and 2 M-HCl from two varieties of red clover were quantified by diode-array RP-HPLC analysis with limits of detection LODs 10-25 nmol dm(-3) in the concentration ranges from tenths of μmol dm^-3 up to 0.4-0.5 mmol dm^-3. Higher levels (by factor 1.5-2) of all isoflavones were found in tetraploid than in diploid red clover.

Full paper in Portable Document Format: 555a285.pdf

Chemical Papers 55 (5) 285–289 (2001)