RESUMO
Nitrogen chemiluminescence detector (NCD) is a nitrogen-specific detector that responds to ammonia, hydrazine, hydrogen cyanide and nitrogen oxide. A method to analyze the herbicide prometryn in plant and water samples was developed using gas chromatograph (GC) coupled with NCD. Extracts from plant (vetiver grass) and water matrices were analyzed for prometryn using an Agilent 7890A GC coupled with an Agilent 255 NCD in a split injection mode with a ratio of 2 : 1. Separation was carried out at 200°C and combustion at 1,018°C with H2 and O2 following optimized method development conditions. The percent recovery of prometryn in the two different matrices tested ranged from 81 to 107%, with relative standard deviations varying from 0.10 to 3.30% for spiked samples. Detection limit of the proposed method was 0.02 µg mL(-1) and the limit of quantification was 0.06 µg mL(-1). The proposed GC-NCD method was successfully applied to determine prometryn extracted from plant and water samples without potential interference of S-triazine, a pesticide from the same group.
