Perfectly said . Sad that is the case but it is so true .
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haha I only did analytical work kicking and screaming the whole way. I have a hypothesis about why there is a distinct lack of analytical chemists at west coast universities and canna companies. Analytical chem requires a extreme OCD for precision measurements and dilutions etc, however, west coasters are relaxed by nature, and cannabis related businesses also attract relaxed people, hence the terrible state of cannabinoid analytical chem services.
But your approach is fully sane. And I’d take an organic chemist to run distillation any day over any other chem discipline its an art so maybe the knuckle dragging pleases the distillation gods i dunno
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I go to a school in the midwest and we have a top 10 analytical chem phd i tell people to start getting into this and it will be useful to them but they are all too lame i think not sure…
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yeah just have to be the kind of person to get off on teh >0.9999 R squared value on standard curve oh yeah
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That would be me, but I’m not a chemist. I’m not an anythingist.
Maybe an antagonist on a good day.
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Flora Research in Grants Pass, Oregon. Lab Director has 25 years as a forensic analytical chemist and is extremely generous with his time and knowledge. He has helped us twice with similar issues …
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Comparing the accuracy of GC and HPLC tests is simple if you understand that with HPLC the THCA answer is multiplied by the theorectical conversion factor of .877 and then that number is added to the d9THC result to arrive at the " total smokable potency". The problem is that the real conversion rate from THCA to d9THC is about .68 because the reaction is never perfect. With GC, the answer is already the real “total smokable potency” number unless the sample is derivitized to prevent decarboxylation from occuring. In practice, if you submit a fresh flower sample to a HPLC lab you will get a number about 20% higher than the GC number. If you submit an already decarboxylated oil to the HPLC lab you get the same number as the GC test.
With GC, the derivitization step is much simpler than most people imagine. If adds about 2 minutes to the sample prep and about 10cents in cost. If you do the derivitization and then get an answer for both THCA and d9THC you are in the same situation as with HPLC. You have to then decide what conversion factor to use to arrive at the " total smokable potency.
With both GC and HPLC it is possible to get ± 5% precision, but this requires attention to detail. There is no fundamental reason why you can’t achieve comparable precision from either GC or HPLC.
The main difference is operating cost. The GC answer costs 15 cents, The HPLC answer costs anywhere from $5-15, a 100:1 difference. With GC you only have to calibrate on one molecule ( d9THC or CBD etc ). With HPLC every molecule requires two calibrations, one for the neutral and another for the acid form. The cost of the acid form calibration standards is 10 times the cost of the neutral form cal standards. And the acid form standards are unstable since they want to decarboxylate even if stored cold. I often suspect that a lot of the variation in lab results has to do with acid form cal standards which have partially decarboxylated and the operators don’t check for this. If an acid form THCA standard has decarboxylated only 5%, the calibration will be based on a lesser amount of THCA, so all the sample results will be 5% high.
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Lab to lab variability is unfortunate but no amount of money or regulation is likely to help. Its just inherent at the current state of the technology. If you have your own GC or HPLC you can probably be accurate within ±10% on any given day with just one sample injected. If you inject 2-3 samples you can take the average and be closer to the truth, but that takes extra time the 3rd party lab can’t afford at the price they charge. If you have your own in-house GC or HPLC then you can decide to run 2-3 samples to be sure.
Hugh Goldsmith
SRI
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Answers like this are why I come to Future4200.
I recently bought a kilo of crude. It’s COA said 62% CBD, my test at Avazyme ( a reliable lab that i use often) said 52%CBD. Both said 8% CBC. Funny thing is it is crystallising in the bottle at about 50% of the mass or more.
The guy I got it from made sure it was some of his best crude as an apology for a previous sample being wildly off the supplied COA. It’s great stuff, very smooth and potent, I just mixed up a batch at 2000mg/oz. It hits hard and clean.
How on earth is it crystallising if it’s only 50-60%?
think you nailed it on the head
Both tests are way off?
It is not common but crystelization can happen at very low concentrations
Time temp and the solvent character of whatever else is in the solution are factors that come into play
Early in my career one of my mentors told me I was a good engineer unlikely to make mistakes but he cautioned me about two things.
- Incorrect analytical.
- Untruthful process operators.
Forty years later I can confirm his wisdom.
Always keep a retainer sample when you go out for analytical data.
It will come in handy sometime.
Always believe the data, not the “but he said.”
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Super-saturation is defined differently for different molecules.
Perhaps 0.5mg/mL is the threshold for CBD crystallization and 0.8mg/mL (or something like that) is the threshold for THCA
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Got some carts tested that I have been smoking fpr two years , no health issues at all. And never felt better ! Still I wanted to know what I was smoking , but got back these crazy ass test results! Wtf ! I know these guys personally and I dont think its cut with anything. Furthermore , I would like to send a sample to antoher lab to see whats really in there.
Thanks
Seems like they put a bunch of random other molecules that don’t have as much of a defined market as D9 with a splash of D9 and told you no details , here smoke this hopefully that 1% will get him a tiny high if he hits it 37 times. Not a scientist either but decent at math. 11.75% cbn , 25.23% CBC , 1.14% D9 , 16.23% D8. Men lie women lie numbers don’t. ( Lab results vary to an extent I’m sure as we’re all aware of )
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That’s cbd distillate reflux into delta 8
Scam imo
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That’s an unusually high CBC number. It may actually be D10. Some labs mistake D10 for CBC depending upon what methods they use.
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Now that would make more since cause they get you super stoney
Please post those results
Interesting find if your bio essaying is correct 