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Carfentrazone Ethyl in Dandelion Root Powder (Dietary Supplement) on Rxi-5Sil MS

ColumnRxi-5Sil MS, 30 m, 0.25 mm ID, 0.25 µm (cat.# 13623)
Sampledandelion root powder spiked with 46 pesticides
QuEChERS Internal Standard Mix for GC/MS Analysis (cat.# 33267)
anthracene for quality control (cat.# 33264)
Conc.:80 pg/µL
Inj. Vol.:1 µL splitless (hold 1.5 min)
Liner:5mm Splitless with wool (cat.# 22975-200.1)
Inj. Temp.:250 °C
Oven Temp.:90 °C (hold 1.5 min) to 340 °C at 8 °C/min
Carrier GasHe, constant flow
Flow Rate:1.5 mL/min
Analyzer Type:TOF
Source Temp.:225 °C
Electron Energy:70 eV
Ionization Mode:EI
Acquisition Range:45-550 amu
Spectral Acquisition Rate:5 spectra/sec.
InstrumentLECO Pegasus 4D GCxGC-TOFMS
NotesPurge valve time: 1.5 min.
Detector mode: full mass range

Sample Preparation:
Wetting: 1 g of dandelion root powder combined with 9 mL of water, shaken well, fortified with pesticides and QuEChERS Internal Standard Mix for GC/MS Analysis (cat.# 33267), soak for 2 hours.

Extraction: 10 mL acetonitrile added then addition of Q-sep Q110 (cat.# 26213), centrifuge with Q-sep 3000 Centrifuge (cat.# 26230).

cSPE: add control standard anthracene (cat.# 33264) to 1 mL extract, add magnesium sulfate to cartridge, use 6 mL Combo SPE Cartridge containing 500 mg CarboPrep 90/500 mg PSA (cat.# 26194), concentrate via evaporation.