2-Dimensional GCMS with Cryotrap: Theory and Applications ...

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2D-GC without Cryotrap:Oven temperature ramps superimposed with the cut window and thechromatogramThe oven ramp begins for column-2 when the oven is already close to its maximum.Oven maxOven TemperatureRamp for column-1Ramp for column-2Cut windowColumn-1 ChromatogramTemperatureTime2D-GC with Cryotrap: The cryotrap freezes analytes at the beginning ofcolumn-2.Peak-of-interestInjectionPort27 psiFIDCut window. Trapped in theCryotrap until thermally released.MSDColumn-1 Column-2GCOven20 psiCryotrapDeans SwitchAn improvement2D-GC WITH CRYOTRAP:• In practice, the cut to column-2 occurs when the oven is already at a hightemperature.• The high starting temperature for column-2 reduces its chromatographicresolution potential.• The introduction of a cryotrap allows the oven ramp for column-2 to beginat a lower temperature.Oven and cryotrap temperature ramps superimposed with the cutwindow and the chromatogram1. During the oven ramp for column-1, the cryotrap cools in preparation for the cut-window.2. The analytes are diverted to from column-1 to column-2 by the deans-switch where theyare trapped by the cold cryotrap.3. The oven is cooled.4. The cryotrap is rapidly heated to release the analytes.5. The second oven ramp begins for column-2.Cryotrap TemperatureCut windowRamp for column-2Oven TemperatureRamp for column-1ChromatogramTemperatureTime
1. During the oven ramp for column-1, the cryotrap cools in preparation for the cut-windows.2. The analytes are diverted to from column-1 to column-2 by the deans-switch where theyare trapped by the cold cryotrap.3. The oven is cooled.4. The cryotrap is rapidly heated to release the analytes.5. The second oven ramp begins for column-2.Oven rampCut windowsCryotrapApplication with CryotrapExample 1: THC and THCC in Blood• CONDITIONS:• TMS derivative• Column-1: DB-17 (phase: 50% phenyl)• Column-2: DB-1 (phase: 100% dimethyl)• (note: the assay without the cryotrap used columns RTX-200 and DB-17)• Expectations:• Sharp Peaks due to focusing• Increased resolution due to full oven ramp for column-2.2D-GC with Cryotrap: The cryotrap focuses the analytes on Column-2.This reduces peak broadening.Cut WindowInjectionPort27 psiFIDPeak of interestMSDColumn-1 Column-2GCOven20 psiCryotrapDeans SwitchExample of Inadequate Resolution without cyrotrap:DB-17 DB-1AbundanceIon 371.00 (370.70 to 371.70): 02-A.DIon 386.00 (385.70 to 386.70): 02-A.DIon 303.00 (302.70 to 303.70): 02-A.D110001000090008000THC-TMS, 4 ng/mL700060005000Partially interfering peak400030002000100009.50 9.55 9.60 9.65 9.70 9.75 9.80 9.85 9.90 9.9510.0010.0510.1010.1510.20Time-->
Page 1 and 2: 2-Dimensional GCMS with Cryotrap:Th
Page 3 and 4: 2D-GCMS: A detector for column-1 en
Page 5: Choice of Column Combinationfor THC
Page 10 and 11: Application 2Example 2: Six Opiates
Page 13 and 14: Case SampleMorphine in 1.0 mL blood
Page 15 and 16: Cryotrap freezes the sample at the

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