GC/FID vs HPLC

The minimal hazardous waste is why i would employ a GC if I had my own operation despite my own preference for hplc

Not to mention being able to test for residual solvents in house, and do some terpene profiling

If money wasnt a thing and i had my own facility - i would have both gc and hplc!

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Yes indeed
from a quick glance it looks like it!

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Learn something new everyday

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that was actually a requirement in the lab I did my thesis in.

you weren’t allowed to leave for the day till you’d learned something.

it was often liberally interpreted and having an 8am lab meeting meant folks would get up and state “I’ve learned something, time to go home” rather early in the day.

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Yes, the GC can measure Vit E, MCT, pg and VG.
All in the same analysis as the terps and cannabinoids.
Hugh
SRI

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Have not had any problems with Vit e so far.
Even if there is some heat related degradation ( which I don’t think is signifigant ) there would be about the same amount of degradation when measuring the standard as when measuring the sample. So you would not really notice the effect.
Just as a side note, molecules do not need to reach their boiling point before starting to move through the column. Generally you try to adjust the temperature program so the molecules travel through the column below the boiling point. That way you get the maximum molecule/column interaction.

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One of the 16 detectors SRI makes is a heated ( 250C typically ) UV ( 254nm ) detector which is mostly aromatic selective and non-destructive

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why do you say it’s actually 0.68? How do you reason that?

pretty sure that 0.68 is empirical rather than “reasoned”…

as in arrived at experimentally.

Thank you for this @cyclopath. It is exactly what I was looking for.

The reaction of THCA to d9THC is not perfect. As cyclopath says, the experimental results don’t support the theorectical .877 conversion. See this doc from Steep Hill Labs ( well respected lab in CA ) which confirms that the real conversion rate is about .68. http://www.srigc.com/cn/downloads/329/BlankImage.pdf
The reason this is important is that HPLC results measure the THCA separately from the d9THC. Then the THCA answer is multiplied by .877 and added to the d9THC result to arrive at the “total smokeable potency” in the COA.
When the anaylsis is performed by GC instead of HPLC the THCA is actually physically decarbed into d9THC at the moment of injection into the hot injection port. So the GC and HPLC answers agree if the conversion factor is .68. If the .877 factor is used for the HPLC results, then the HPLC results are higher, but based on a theoretical number instead of a real number. Most state laws require the .877 number be used.