GCxGC-TOFMS Chromatogram of QuEChERS Extract of Red Bell Pepper Showing Incurred Pesticides Using Rxi-5Sil MS and Rtx-200

Injection
Column	Rxi-5Sil MS 30 m, 0.25 mm ID, 0.25 µm (cat.# 13623)
	Rtx-200 1.5 m, 0.18 mm ID, 0.20 µm (cat.# 45001)

Standard/Sample	Pesticides in red bell pepper extract
	QuEChERS internal standard mix for GC-MS analysis (cat.# 33267)

Diluent:	Acetonitrile
Inj. Vol.:	1 µL splitless (hold 1 min)
Liner:	Gooseneck splitless (5 mm) w/deactivated wool (cat.# 22973-200.1)
Inj. Temp.:	250 °C
Purge Flow:	40 mL/min
Oven
Oven Temp.:	Rxi-5Sil MS: 90 °C (hold 1 min) to 310 °C at 4 °C/min (hold 2 min) Rtx-200: 100 °C (hold 1 min) to 320 °C at 4 °C/min (hold 2 min)
Carrier Gas	He, corrected constant flow (1.8 mL/min)
Modulation
Modulator Temp. Offset:	25 °C
Second Dimension Separation Time:	4 sec
Hot Pulse Time:	1.2 sec
Cool Time between Stages:	0.8 sec

Detector	TOFMS
Transfer Line Temp.:	290 °C
Analyzer Type:	TOF
Source Temp.:	225 °C
Electron Energy:	70 eV
Mass Defect:	-20 mu/100 u
Solvent Delay Time:	5 min
Tune Type:	PFTBA
Ionization Mode:	EI
Acquisition Range:	45-550 amu
Spectral Acquisition Rate:	100 spectra/sec
Instrument	LECO Pegasus 4D GCxGC-TOFMS
Sample Preparation	Internal Standard: 100 µL of QuEChERS internal standard mix for GC-MS analysis (cat.# 33267) and 100 µL of QuEChERS internal standard mix for LC-MS/MS analysis (cat.# 33261) were added to each 10 g sample. These internal standard mixes require no dilutions and contain compounds specified in the EN 15662 QuEChERS method. Extraction: 10 mL acetonitrile was added to a 10 gram sample of homogenized red bell pepper. After a 1 minute shake, Q-sep European method extraction salts (cat.# 26236) were added followed by another 1 minute shake. The sample was then centrifuged with a Q-sep 3000 centrifuge (cat.# 26230). dSPE: Add 1 mL extract to QuEChERS dSPE cleanup tube containing 150 mg MgSO₄, 25 mg PSA, and 25 mg C18 (cat.# 26216). Shake for 30 seconds and centrifuge with a Q-sep 3000 centrifuge (cat.# 26230).
Notes	Rtx-200 (cat.# 45001) is a 10 m column. A 1.5 m section was cut off and used as the second dimension column.

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