Gas Chromatography - Mass Spectrometry

March 25 2019 1 Comment(s)

GC-MS (Gas Chromatography-Mass Spectrometry) analyzes an oil by taking a small sample and volatilizing it into a gas using increasing heat so it can move through a special column. This is the Gas Chromatography portion of GC-MS. While moving through the column, the molecules naturally separate based on their weight, polarity, and size. This separation happens as lighter, smaller components travel faster than the heavier, bulkier components through the column. As these components exit the column, they are recorded as peaks on a chromatogram.  The sample components then move to the Mass Spectrometer, where they are hit with 70 eV of electrons. These electrons break the sample into fragments and ions, which move through an accelerator. These fragments and ions are then measured and a spectrum is produced.

The resulting graph from this process shows the peaks of each component in their proportionality to the sample. A reference library of components can automatically identify the peaks as each component present.

Most labs run a GC-MS for 20 minutes, however, we have found that such a short run fails to detect all of the heavier components. APRC runs a GC-MS for nearly two hours in order to record all of the components. Once the run is finished, a chemist is able to analyze the resulting graph to determine if an oil meets the standards in its category.


Watch how the GC-MS works on our YouTube channel.

Comments and responses

  • Rose Bachman:

    07 Apr 2019 02:00:00

    I am fascinated with what I’ve learned from APRC at doTERRA’s 2018 Convention. I work at a High School and assist students in a Chemistry Class. Is the nano technology that has been used to test doTERRA’s oils going to be able to test other oils to help create a standard so Essential Oils may someday be able to be authorized for specific uses by the FDA?

    Thanks, Rose Bachman

    Hi Rose! Thanks for your support. To clarify, APRC's testing of oils is not "nano technology." Our primary method of testing is gas chromatography-mass spectrometry. There is a current basic standard for oils, which is set by the International Organization of Standardization (ISO). ISO standards simply set what compounds should be present in an oil in a range of percentages. The FDA regulates how specific products are used, so standards are helpful for purity, but not necessarily usage.

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