- The Concentration Of The Pesticide Metribuzin Must Be Determined In A Sample With Potatoes First 15 00 Grams Of The Po 1 (131.88 KiB) Viewed 36 times
The concentration of the pesticide Metribuzin must be determined in a sample with potatoes. First, 15.00 grams of the potatoes are homogenized. It homogenized sample is then added 15 ml of acetonitrile and 150 avl of an internal standard solution containing 20 ng/ul with isotope-labeled Metribuzin (d - 3 Metribuzin). After centrifugation, the acetonitrile phase is transferred to a new one test tubes. The acetonitrile phase then undergoes a QuECHERS purification, and finally, some of the acetonitrile extract is analyzed together with 5 calibration solutions using GC-MS. Overview of the composition of the calibration solutions as well as measured peak areas for all the samples are given in table 1. Calculate the concentration of Metribuzin (ng/g) in the original potato sample. Table 1: The concentrations of Metribuzin and internal standard (d-Metribuzing in five calibration solutions (K1-K5) as well as measured peak area for Metribuzin and IS in all solutions. Solutions Concentration of Metribuzin (ng/ml) Concentration Top area, Top area, of IS Metribuzin ICE (ng/ml) 200 145223 598889 K1 50 K2 100 200 296711 584045 K3 200 200 605439 594286 K4 300 200 912295 604314 K5 400 200 1234002 594478 Potato sample 774682 569029