ABSTRACT
A method is described for the simultaneous determination of sixteen organochlorine pesticides in drinking water using automated solid-phase extraction followed by high-volume (80 microliters) capillary column gas chromatography using electron capture detection. The fully automated extraction method followed by high-volume injection permits rapid sample analysis compared to previously described procedures since no further pre-concentration of the analytes is necessary after they have been eluted from the octadecyl solid-phase extraction cartridge. The lowest detectable concentrations of the pesticides are between 1-5 ng l(-1), relative recoveries range from 92-105% in tap water spiked at 100 ng l(-1) and the relative standard deviations are in the range 5-12%.
Subject(s)
Autoanalysis , Chromatography, Gas/methods , Hydrocarbons, Chlorinated , Insecticides/analysis , Water Pollutants/analysis , Water/analysis , Microchemistry , Reproducibility of ResultsABSTRACT
Supercritical fluid extraction (SFE) followed by packed column supercritical fluid chromatography with ultraviolet detection was evaluated as a quantitative method for determining 4 antifungals (fluconazole, tioconazole, hexaconazole, and UK-47,265) in rodent diet. Chromatography was achieved with a cyano-bonded silica column, UV detection at 210 nm, and methanol-modified supercritical carbon dioxide as mobile phase. The effects of modifier concentration, temperature, and column pressure on antifungal retention time was studied. Off-line SFE was optimized at 2 spike levels, ranging from 0.5 to 10 g/kg, for each of the 4 antifungals. Average recoveries ranged from 79.0% for UK-47,265 to 96.5% for hexaconazole. Overall, the procedure provides a suitable method for analyzing antifungals in spiked rodent diet.