Unknown Grass GC/MS and Getting GC/MS Running in New Lab Space
Shimadzu GC/MS now moved to 114 lab
Found SPME with CAR-DVB-PDMS filament (Sepulco)
Cleaned filament with two runs on GC/MS
(up to 270 centigrade)
- Ran blank tap water (used from sink on back wall), but didn't have MS time matching GC run time for the first two runs. This is probably okay for the tap water blank, but the unknown grass sample will be redone.
- Made two unknown grass extracts (0.25 g dry grass matter-this dried out in the freezer, so likely still has volatiles from the summer, however, the -20 centigrade freezer was moved and may have warmed up in the process)
- Collected first unknown grass extract (UNKGR 1.1 4/20/19) for 15 minutes and ran on GC/MS with incorrect end times. Recollected this sample and reran on GC/MS with GC/MS temperature program from Yang et al. (2019) ([1]).
- oven temp starts at 40 centigrade
- raise temp to 190 centigrade @ 3 centigrade/min, hold for two minutes
- raise temp to 290 centigrade (modified to 270 centigrade per rage of temps recommended for this filament), at 10 centigrade/min, hold for ten minutes.
grass samples shipped from Orono at the end of the summer 2018 (likely August, 2018), the grass smelled rancid. The large block of grass in the center seemed freezer burned with ice chunks while the edges were dried out, the grass from the edges was used for the extractions made today. 4 mL of water was used instead of 3 mL because the grass was difficult to grind up and needed to be mostly covered in water.
|
Project name
Main project page