Thank ya!
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care of @Photon_noir
Alkaline Beam Test: Colorimetric testing for CBD
Preparation of Solution & Workspace
- Fill plastic graduated cylinder with about 70mL of 95% ethanol.
- Weigh out 4g KOH on wax paper and add it to alcohol.
- Swirl or stir with stainless or glass rod to dissolve all KOH.
- Finish filling graduated cylinder up to 100mL line with ethanol
- Label the clean glass jar “5% KOH in EtOH, CBD Beam Test” or similar, then pour the entire solutioninto the jar and seal the lid. Swirl a bit to mix well.
- On a paper towel next to the jar, write “Beam” or similar and place a new plastic pipette on it.
- On another paper towel next to the reactor, write “RXN” or similar and place a new plastic pipette onit, also.
- Set up several test tubes with lids in a rack next to the KOH solution and Beam pipette.
☆ Sampling & Testing
- Squirt the rxn solution sample into the uncapped test tube in the rack.
- Unseal the jar and remove the lid (or lid ring) to pull a little bit of KOH test soln from it. Only a fewdrops are needed.
- Squeeze one (1) drop test soln into the tube with the rxn sample and swirl the tube for 2 seconds tomix.
- Observe the color after 5 seconds. If color is light or invisible, add 1 to 3 more drops of KOH soln,swirl 2s. Odd color may show up upon resting for too long or excessive stirring, so only read color reactions that occur immediately (i.e. 1st color under 30 seconds).
7. Take notes with time and dispose of sample.
if you’d like to buy that, I’m happy to take donations.
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And thank ya for the title change… was about to do it😂
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kind of a different topic but isnt there a similar quick and simple test you can do to determine if decarb is complete?
Maybe we can add that to this short thread and make the title represent both processes. (i did a search and couldnt find it but swear i have seen it here somewhere)
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bromocresol green. It’s in Tricks of the trade - #655 by CdpIchem
And I’ve linked it in multiple other places…
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Thanks!! I knew you would know where it was.
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Great idea!
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I’m betting the TLC plate can be replaced with a filter paper…
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Oddly, it does not! Lower right hand corner of a TLC plate are samples of a decarb product and a crude sample. The center is a paper filter and the ones on the right were spotted on plain paper. Interesting, no?
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Thank you!
Pity.
Great thing about being wrong is I learned something 
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Now I’m curious! I wonder if just gypsum would work or if the silica is a necessary ingredient. I wonder if another adsorbent would work either (I see a future use for all that zeolite dust that seems to accumulate in our media drying ovens)
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drywall?!?
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It’s traditionally “the other stuff” in TLC plates so who knows. Certainly cheaper to buy your analytical supplies at home depot than sigma
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Calcium carbonate, gypsum and other such natural materials wer among the first ever used to perform chromatography! 
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this works for sodum hydroxide as well.
I have had traces of CBD show up pink even when doing sodium bicarbonate washes.
I think the colour change will work with all alkali bases.
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If the weight samples (let’s say dried flower or distillate) were the same, can they show the CBD potency relative to another sample?
If you hit cbd oil and a spectrophotometer a simple calibration curve will help answer that question.
I think it just shows the relative concentration, I didn’t weigh the samples out
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