Identification and quantification of natural isoxazolinone compounds by capillary zone electrophoresis

A capillary zone electrophoresis (CZE) method that is specific, simple, rap id and also cheap was developed to analyse some natural UV-absorbing isoxaz olinone compounds with toxic potential present in legume seedlings. The six most common natural isoxazolinone compounds were separated within 10 min w ith 25 mM potassium phosphate (pH 7.5) containing 8% 1-propanol as running buffer. A 60 cm coated fused-silica capillary (52.6 cm effective lengthX75 mum I.D.), with an electric field of 375 V/cm at 30 degreesC was used. The limit of detection ranged from 0.01 mM (3.0 mug/ml) to 0.03 mM (7.7 mug/ml) . Linearity between peak areas and concentrations ranging from 0.05 mM to 1 .75 mM were determined for each isoxazolinone. The correlation coefficient was 0.9954 or greater. Both relative migration time and peak area were repr oducible. The RSD of relative migration time is between 0.44 and 1.94% and RSD of peak area is between 1.26 and 6.86%. The concentrations of isoxazoli nones in Lathyrus odoratus and L. sativus seedlings obtained by CZE were in agreement with the previous results from HPLC. (C) 2001 Elsevier Science B .V. All rights reserved.