Resumen

MENDIETA, Claudia J.; ORTEGA, Nicole A.; SOLANO-CUEVA, Natalí  y  FIGUEROA, Jorge G.. Development of a method for the quantification of organochlorine pesticides by GC-ECD-MS. Rev Politéc. (Quito) [online]. 2017, vol.40, n.1, pp.21-28. ISSN 2477-8990.

In Ecuador the use of pesticides has been a problem due to the concentrations used are higher than the maximum allowable limits. The agencies that control this type of compounds do not have sophisticated technologies like tandem mass spectrometry or time of flight, and use the same equipment for different analysis. For these reason sometimes two columns are installed simultaneously, which consequently can be a problem with the maximum temperature that can use. The aim of this work was to develop a methodology to quantify 32 organochlorine pesticides by gas chromatography using electron capture detector and mass spectrometry with a low oven temperature. Different conditions of temperature ramp, stationary phase, injector temperature, carrier gas flow, purge flow and injection mode were evaluated. Only injector temperature and carrier gas flow had no effect on the peak area. Using a DB5-ms column and the same temperature ramp, 24 pesticides were separated. Although different oven temperature programs were tested, three pairs of pesticides shared the same elution time, but the identification was achieved using selected ion monitoring mode. The correlation coefficient of the calibration curves was greater than 0,99. The detection limits found were lower than the maximum residue levels allowed.

Palabras clave : Gas chromatography; organochlorine pesticides; validation.

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