UPLC-MS/MS Determination of Atrazine and Carbofuran in Water

Atrazine and carbofuran in water sample were separated and enriched by passing through C18 SPE column. The SPE column was dried by N2-blowing and eluted with dichloromethane to desorb the analytes. The eluate was evaporated to dryness by N2-blowing and the residue was dissolved with 1 mL of the solvent mixture of methanol and dil. formic acid (0.1+99.9) mixed in the ratio of 40 to 60. The solution obtained was used for UPLC-MS/MS analysis. The waters BEH C18 chromatographic column and mobile phase of methanol and dil. formic acid (0.1+99.9) were used for separation by gradient elution. The determination by the MS/MS was performed under the conditions of electrospray ionization source, positive ion scanning and multireaction monitoring. Linear relationship between values of peak area and mass concentration of either of the pesticides was found in the same range of 0.10-10.00 μg·L-1, with same value of detection limits (3S/N) of 0.15 ng·L-1. Tests for recovery were performed by addition of the pesticide standards at 3 concentration levels (i.e. 0.10, 0.50 and 5.00 μg·L-1) for 5 parallel determinations each, results of average recovery found were in the range of 77.0%-102.2% with RSD′s (n=5) ranged from 2.9% to 7.6%.