QUANTITATIVE-ANALYSIS OF PESTICIDES BY CAPILLARY COLUMN HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY COMBINED WITH SOLID-PHASE EXTRACTION

High performance liquid chromatography (HPLC) combined with solid-phas e extraction was reported on, for simultaneous analysis of pesticides in this work. The separation of 12 pesticides was achieved on a C-18 c apillary column with gradient elution. Sub-microlitre injection volume of the samples and a U-shaped 35 nl flow cell were used to improve th e separation and detection. In addition, the method used C-18 solid-ph ase extraction disks to allow a 250-fold enrichment of the pesticides from fortified water and apple samples. The calculated detection limit s range was 0.15-0.8 mu g/l. Under the optimal extraction conditions, recoveries of 85-107% for most of the pesticides at 1.0-10.0 mu g/l le vel, were obtained. (C) 1998 Elsevier Science B.V.