AZDA SCIENCE PHOTO OF THE MONTH JANUARY 2019
SAL scientists validate a new testing method to determine if it can reliably extract the residue of a pesticide of interest. The dark substance in the bottom of the test tubes above is soil and the clear fluid (supernatant) above the soil is a solvent containing the pesticide residue. Further clean up steps follow before analytical instrument analysis is performed to determine the identity and amount of the pesticide present in the original sample.
This particular test is a variant of the QuEChERS method. QuEChERS is a solid phase extraction procedure which can be quickly adapted for many of today's pesticides. QuEChERS is a portmanteau word for "quick, easy, cheap, effective, rugged, and safe".