Hey all,
I am looking for a better method of extracting cannabinoids from our vegan chewables for HPLC analysis.
Of note:I do not have access to a cryo grinder.
Thanks in advance!
What are the other ingredients in your vegan chewables? You can probably do an aqueous addition to those, digest the other materials, and then do a solvent extraction for your cannabinoids (assuming your other ingredients are not soluble in your selected solvent). Then you could evaporate that solvent and tada you have a concentrate that you can use standard prep with.
Feel free of reach out if you want to discuss the process a bit more. Method development is something I like to do. 
1 Like
So a little more info would be needed here…
Do you care if you inject sugars onto your column?
What are the ingredients you’re extracting from?
What cannabinoids are you messing with?
Whats the concentration in each gummy?
What methods do you think you will be employing to homogenize the gummies?
What solvents do you have for dissolving the gummies?
What are the solvents for your HPLC?
I could probably ask more questions but I think this is the right amount as of now.
EDIT: Whats the range for your calibrations?
So…
Currently I melt the whole gummie in 20ml water at 75C. I add 10ml MeCN and shake once. I add 4g MgSO4 and 1g NaCl and vortex for 10 minutes.(Quetcher method)
I centrifuge for another 5 minutes and do a 100x dilution in MeCN to present it to the instrument.
Our gummies are anywhere from 10-20 mg CBD/gummie.
I try to keep the column as clean as I can for obvious reasons.
I have MeOH,EtOH,chloroform,THF and DMSO at my disposal for solvents.
My foes are carnuba,pectin,coconut oil and tapioca starch.
This works fairly well but I feel like Im not extracting as efficiently as I can be and I know testing labs are doing it better.
Dissolve it on high heat (60c?) In a stirring bath of water and heptane. The sugars and water solubles will go into your water layer. Discard water.
Do 3 or more washes with methanol on your cannabanoid rich heptane layer. Most of the fat and wax should stay with the heptane. Your methanol should have all your cannabanoids.
Then just evap and test in whatever solvent you want?
2 Likes
you could use liqN2 and a morter and pestle to substitute for that fancy “cryo-grinder”.
I ground a lot of biomass (for DNA) in disposable 15ml tubes using liqN2, a glass rod, and a vortex mixer once upon a time. pretty sure you could play the same game.
think larger version of this device
Edit: I used both round bottomed and conical tubes (15ml). with a formed glass rod. At the 20year mark I couldn’t tell you which was more effective, but I’m pretty sure the round bottom tubes were cheaper 
didn’t do near as many preps tissue preps in the eppie tubes, but I’ve definitely used them with LiqN2.
4 Likes
If he’s already in MeOH he might not even need to evap and re-dissolve. MeOH works just fine for potency testing and is used in the international UN method.
Here’s a link to see which solvents are miscible - so that you know what will create a solid layer with the solvents you already have on hand.
You want to pick one that the cannabinoids are soluble in but that your gummy ingredients are not soluble in. I see you have listed your gummy ingredients, but I’m not going to look up all their solubility profiles.
Good luck with your quest. @cyclopath process of bench scale cryo-grinding sounds great, the smaller the particle the more surface area and hypothetically the better your cannabinoids will be recovered.
2 Likes
I agree with @cyclopath that cryogrinding is going to be the absolute best way to homogenize the gummy but I suppose if you are able to dissolved the entire gummy in water then that should work. The only problem I see with that is the more gummy you put in there the more undesirables you have to tango with. If you freeze then cut up the gummy and homogenized by hand quickly that could work for getting a smaller representative amount. I was thinking dissolving in about 20 mL water vortex for about one min sonicate for 30 minutes add 20 mL MeOH vortex for 1min sonicate 30 min then vortex for 1 min. This next part I don’t know how well it would work but if you wanted to saturate your water layer with salt that should push the MeOH and water away from each other. For 20mL I think that would take about 7.14g of NaCL. Then since you have two layers then you can just pipette off the top layer and dilute that accordingly. You’re probably going to have oils in your organic layer so maybe run through a 0.2 micron filter just in case. There is a way to check and see if your method is efficient by putting a known concentration and amount of distillate on a gummy homogenizing and then using your method to see how much you actually extracted. Also third party labs are doing it “better” because they are injecting sugars and shit onto their column and throwing them away when they don’t work anymore.
2 Likes
I’ve got the distinct recollection of the postdoc on the bench kitty corner to mine having a dedicated coffee grinder she used for RNA work. 98% sure she was using LiqN2 in a Braun.
the trick is to let essentially all the LiqN2 evaporate before your 3 sec grind (same is true for mortar & pestle, test-tube & vortex).
On the off chance that I’m wrong (she may have been cooling the grinder with dry ice, then adding Liquid N2 frozen biomass rather than freezing it in the grinder), you might want to start with something less expensive (postdoc was German )
1 Like
I know that isopropyl and dry ice get down to -78C maybe thats a good start for freezing cheaply.
So much this!
I talk very closely with one of the 3rd party labs that we use and I even had them send over SOP’s on how they prep different products. Saw that they don’t use quetchers and asked why. He said bc we just throw the damn things out like nothing. So I figured I would slide that in there for the in house chemists who know the struggle of keeping a clean column.
2 Likes