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Agilent 8890 GC-MS

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Agilent 8890 GC-MS#

Procedure#

  1. The GC-MS must remain under high vacuum, so it is always on. Open the Agilent GCQQQ software.

  2. Go to Method ‣ Load Method and find butterscotch.M.

  3. Click the big arrow at the top of the screen.

  4. Type your name in under Operator Name. For Data Path, click Browse. Save your data under D:/MassHunter/GCMS/1/data/practice. Name your data file something fun and interesting.

  5. Take a look at the sample racks above the GC-MS. We’ll be using the Butterscotch extract which is already loaded in one of the trays. Find it! Note that the trays have numbers corresponding to the individual vials, but also numbers corresponding to the racks present. Two rows of racks are numbered 1-3. The racks on the left are correct. The racks on the right are actually racks 4-6. On the computer, type in the vial number for the Butterscotch Extract and select the correct rack from the dropdown (making sure that you translate 1 to 4, 2 to 5, and 3 to 6).

  6. OK and run method!

  7. It may appear as if nothing is happening at all as it warms up. Please be patient. The PAL autosampler will play some tunes right before it’s about to move.

  8. Once the run is complete, open the Qualitative Analysis software. Find your data file and open it. If nothing has changed, it should automatically identify all of the peaks in your data.

  9. Once you’re finished looking at the software, you may close it.

  10. If you are the last person using the GC-MS, go to Method and load the standby.M method (just look through the drop down menu as it should have recently been used).

Attention

When the entire class is finished using the instrument, be sure to set the method to standby.M. This decreases the flow rate of He (expensive!) and lowers the average temperature of the instrument.

Questions#

  1. We operated the GC-MS in “headspace” mode which means it just pulls off the vapor at the top of the sample without actually dipping into the liquid. Knowing that, what was the purpose of the incubation/shaking chamber?

  2. Were all of your peaks well resolved?

  3. Name 3 compounds that were identified by the software. Compare that to the list of ingredients on the original bottle. How does what you found differ from the label on the bottle?

  4. Can you determine which compound is most concentrated based on this run? How or why not?

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