Non-aqueous capillary electrophoresis with diode array and electrospray mass spectrometric detection for the analysis of selected steroidal alkaloidsin plant extracts
S. Cherkaoui et al., Non-aqueous capillary electrophoresis with diode array and electrospray mass spectrometric detection for the analysis of selected steroidal alkaloidsin plant extracts, J CHROMAT A, 922(1-2), 2001, pp. 321-328
Nonaqueous capillary electrophoresis coupled to UV detection is described f
or the separation and determination of steroidal alkaloids. After optimizat
ion of electrophoretic parameters, including the electrolyte nature and the
organic solvent composition, a reliable separation of solasodine and solan
idine was achieved in a methanol-acetonitrile (20:80, v/v) mixture containi
ng 25 mM ammonium acetate and 1 M acetic acid. For quantitative purposes, a
fused-silica capillary with a bubble cell was used and detection was perfo
rmed at low wavelength (195 nm). Method performances, including migration t
ime and peak area reproducibility, Linearity, sensitivity and accuracy, wer
e also evaluated. The method was applied to determine solasodine in Solanum
elaeagnifolium berries and Solanum sodomaeum leaves and seeds. To further
improve sensitivity in the analysis of solasodine-related compounds, solani
dine, demissidine and tomatidine, the developed method was interfaced with
electrospray ionization mass spectrometry. In the case of solasodine, the d
etection limit was estimated at 3 mug/ml for NACE-UV and at 0.05 mug/ml for
NACE-MS, in the selected ion-monitoring mode. (C) 2001 Elsevier Science B.
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