NIR system CBD/THC testing method development.

Hi everyone, I’m using a Buchi NIRFlex with the solids attachment. Have no time for the lengthy calibrations. Would anybody on here no someone or a company that I could hire in order to speed up this process. We intend on using this for internal quality control, quick testing biomass coming in etc…

Thanks for your time,
Cheers,
Nick

n.meyerman@companyx.ch

Waiting for your job/contract offer

Why are using IR? It will produce a mess of convoluted signals. As for differentiating CBD and THC, they both have 1,1-disubstituted olefins that will absorb at 850-900 cm-1…CBD has two of them. Also relying on a C-O ether signal at about 1000cm-1 isn’t good either.

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HPLC, GC, UV-Vis. If you do IR, you will have to to do Raman.

Not sure I follow, Raman and infrared are different spectroscopic techniques

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Near ir takes complex signals and uses them as a fingerprint, think of the 500-1000 cm-1 region

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I understand IR. It’s used to identify functional groups using vibrational energy and Fourier transform. THC and CBD have the same functional groups present.

The fingerprint is a region below 1000 cm-1 that are unique to each individual molecule. The problem is that fingerprint regions are complex and it is not easy to tell what the peak is representing.

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Raman spectroscopy is the complementary and necessary technique that goes with IR. Some things only show up in IR and some only in Raman. Many things can show up in both. I can’t think a legitimate way to do what’s been asked with only a NIR.

Edit: Link and a little more.

Raman probes the same information as IR but in a different manner.

https://www.digilabglobal.com/identity-cannabis

An example. I know nothing of this one.

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The best you could do is standardize on a known similar to what you will be getting. You could then qualitatively tell if it’s drastically different, but you would miss lots of little differences.

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That is true but the molecule in question needs to have a point group that is not c1. None of the cannabinoids have any symmetry so it’s point group is c1. The character table for c1 only has the identity operator. It is only IR active.

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The links broken, but I have my own flow chart. Click the link I posted. They have data right on the home page. Raman is next level analytical. That’s why they cost too much.

Edit: Spelling

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near ir analysis doesnt try to assign any peak to a particular functional group, but uses computers and sometimes even machine learning to use fingerprint to point to specific molecule

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Sweet, I love me a good ol spectroscopy pissing contest

Have any of you actually used Raman? Its a finicky bastard… I wasted a good year of grad school blasting proteins with raman and I can assure you that things with point group of C1 show up, its just certain vibrations that lack the symmetry to be raman active. If that werent the case then almost all chiral molecules would be Raman inactive

Raman its not a good technique for cannabinoid testing, haha and I’d love to see someone try to smear crude onto a gold mirror and try to analyze the spectrum lol. and good fkn luck getting quantitative result, hahahaha

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https://landing.steephill.com/whitepaper

Or search near ‘infrared spectroscopy steephill’. I think they started to do this late last year around October? Only useful for solid samples like flower. I wonder if you could use it on solid concentrates like shatter or rosin. My guess is that the response doesn’t stay very linear once you get to the higher (>30%) concentrations.

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I was wrong about what makes a vibration Raman active,

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Raman has come a very long way. There are absolutely some that are horrible to try to run. And there are others doing QC for pharma that are completely automated. There are even handheld ones now. I have run many a Raman.

But, the question was doing this with NIR. I wouldn’t do that myself. Because I feel IR only gives half the story unless you are lucky.

And in my experience IR isn’t any easier than Raman.

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