Development and Validation of a Simple and Efficient Method for the Determination of Pendimethalin and Its Metabolite M455H001 in Soil by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS).

A new analytical method has been developed and described for the rapid determination of pendimethalin and its major metabolite M455H001 in soil by liquid chromatography coupled with ion-spray tandem mass spectrometry (LC-MS/MS) after a single acidic solvent extraction. The chromatographic separation of the analytes was achieved using a Zorbax C18 reversed phase column and water/0.1% formic acid and methanol as the mobile phase at a flow rate of 0.2 mL min⁻¹. The recoveries of the method ranged from 78.8% to 119.8% for pendimethalin and from 73.7% to 108.8% for M455H001, and the relative standard deviation was lower than 16% for both analytes. The validated limit of quantification was 0.01 µg g⁻¹ soil dry weight for both compounds. The matrix effects were evaluated and were less than 20% for both substances in the examined soil samples. It is concluded that the method is easy, with reasonable consumption of reagents, characterized by reliability and sensitivity, and therefore, it is suitable for monitoring the levels of pendimethalin and its major metabolite M455H001 in soils. [ABSTRACT FROM AUTHOR]