THE OPTIMIZATION OF STEP-GRADIENT ELUTION CONDITIONS IN LIQUID-CHROMATOGRAPHY - APPLICATION TO PESTICIDE-RESIDUE ANALYSIS USING COUPLED-COLUMN REVERSED-PHASE LC
Sm. Gort et al., THE OPTIMIZATION OF STEP-GRADIENT ELUTION CONDITIONS IN LIQUID-CHROMATOGRAPHY - APPLICATION TO PESTICIDE-RESIDUE ANALYSIS USING COUPLED-COLUMN REVERSED-PHASE LC, Chromatographia, 42(1-2), 1996, pp. 17-24
Citations number
20
Categorie Soggetti
Chemistry Analytical","Biochemical Research Methods
A computer spreadsheet application has been developed for the optimiza
tion of step-gradient elution conditions as applied in coupled-column
RPLC for online clean-up and separation in the analysis of pesticide r
esidues. The procedure is based on the experimentally determined reten
tion behaviour of the analytes as a function of mobile phase compositi
on. Retention and peak volumes of the analytes eluting under isocratic
and one- and/or two-step gradient conditions can be calculated. For a
given set of analytes, the spreadsheet systematically calculates the
resolution of the least efficiently separated pair of peaks in the spa
ce defined by the eluotropic strengths of the mobile phases and the ti
me at which the step-gradient takes place. The performance of the prop
osed procedure was tested and evaluated for the analysis of nine polar
pesticides for which in a previous study adequate conditions had been
found by computer-aided chromatogram simulation. The optimum conditio
ns predicted by the procedure were in good agreement with those establ
ished experimentally and by simulation. The simultaneous production of
data on retention, peak volume and resolution for a group of analytes
under selected one- and/or two step-gradient elution conditions makes
the calculation procedure highly productive and flexible in searching
for and/or adjusting appropriate separation conditions.