Determination of explosives in environmental water samples by solid-phase microextraction-liquid chromatography.
When explosives are present in natural aqueous media, their concentration is usually limited to trace levels. A preconcentration step able to remove matrix interferences and to enhance sensitivity is therefore necessary. In the present study, we evaluated solid-phase microextraction (SPME) technique for the recovery of nine explosives from aqueous samples using high-performance liquid chromatography with ultraviolet detection (HPLC-UV). Several parameters, including adsorption and desorption time, coating type, rate of stirring, salt addition, and pH, were optimized to obtain reproducible data with good accuracy. Carbowax coating was the only adsorbent found capable of adsorbing all explosives including nitramines. Method detection limits (MDL) were found to range from 1 to 10 microg/L, depending on the analyte. SPME/HPLC-UV coupling was then applied to the analysis of natural ocean and groundwater samples and compared to conventional solid-phase extraction (SPE/HPLC-UV). Excellent agreement was observed between both techniques, but with an analysis time around five times shorter, SPME/HPLC-UV was considered to be applicable for quantitative analysis of explosives.
Biotechnology Research Institute, National Research Council of Canada, Montreal, Que, H4P 2R2 Canada.
Fanny
F
Monteil-Rivera
Chantale
C
Beaulieu
Stéphane
S
Deschamps
Louise
L
Paquet
Jalal
J
Hawari
D000327:Adsorption; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005107:Explosions; D006863:Hydrogen-Ion Concentration; D015203:Reproducibility of Results; D012492:Salts / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet / Q000379:methods*; D013995:Time; D014867:Water / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D012492:Salts; D014874:Water Pollutants, Chemical; D014867:Water