C. Hidalgo et al., TRACE DETERMINATION OF TRIAZINE HERBICIDES BY MEANS OF COUPLED-COLUMNLIQUID-CHROMATOGRAPHY AND LARGE-VOLUME INJECTION, Analytica chimica acta, 338(3), 1997, pp. 223-229
Coupled-column liquid chromatography (LC-LC) with ultraviolet detectio
n was used for the trace-level determination of simazine, atrazine, te
rbuthylazine and terbutryn in environmental water samples. A sample vo
lume of 2 mi was directly injected in the chromatographic system, usin
g two reversed-phase C-18 coupled columns. The mobile phases consisted
of two mixtures CH3CN/H2O, one with 40% of acetonitrile (M-1) and one
with 70% (M-2). As a result, a rapid procedure with detection Limits
down to 0.1 mu g l(-1) was developed. The method was validated by mean
s of recovery experiments. Drinking and surface water samples were spi
ked at 4 and 0.4 mu g l(-1) yielding average recoveries between 86-104
% (n=5) with coefficients of variation between 1-6%. The overall proce
dure allowed a sample throughput of up to 60 samples per day. Surface
water samples from a wet area of Castellon (Spain) were analyzed by me
ans of the proposed LC-LC procedure, thus simazine, terbuthylazine and
terbutryn were detected at sub-mu g l(-1) levels. Lower detection lim
its, between 0.02-0.05 mu g l(-1) were reached by preconcentration of
100 mi of water samples on C-18 bonded phase solid phase extraction (S
PE) cartridges. Drinking water samples spiked at 0.1 mu g l(-1) were p
reconcentrated and analyzed by LC-LC yielding average recoveries betwe
en 84-103% (n=3) with coefficients of variation between 2-5%.