Determination of Acid Herbicides via Direct Injection LC/MS/MS

New Organic Monitoring Techniques - Session 2
Oral Presentation

Prepared by N. Rasnake, L. Loftis
Pace Analytical, 12065 Lebanon Road, Mt Juliet, Tennessee, 37122, United States

Contact Information: [email protected]; 615-773-5947


A direct method with LC/MS/MS using triple quadrupole technology coupled with a simplified hydrolysis extraction was developed for low ppb detection of herbicides in both soil and water matrices. The method utilizes an Agilent 1290 Infinity II liquid chromatography system coupled to an Agilent 6470 LC/TQ mass spectrometer. Both soil and water samples were hydrolyzed using a simplified extraction process. The developed method is significantly faster than EPA method 8151, both in extraction and analysis, and achieves a Limit of Detection (LOD) of 1.5 μg/L for all target analytes. Analytes are determined under direct injection conditions between a range of 2 to 50 μg/L. The MS/MS acquisition method utilizes dynamic Multiple Reaction Monitoring (dMRM), which provides increased sensitivity and confidence in identification of target analytes. Method validation was done in both matrices with a 2 μg/L method Limit of Quantitation (LOQ) achieved.