Chromatography Forum

I am looking for some simple sample prep for marijuana leaves/buds. This needs to be fast and reliable. I saw bunch of examples on the web but may be somebody can recommend "out-of-the-box" solution. If there is a review on the subject I would appreciate the reference.

I can't help but grin when I suggest this. Google "herb grinder". You'll find a cylindrical stainless steel device designed such that the top half and bottom half can rotate independently of each other. Inside there are machined teeth that grind the material very finely. Some have screens that allow finer particles such as trichomes to fall through and be collected separately, but I imagine you'd want to keep everything together. In that case avoid the "3 part" and "4 part" models and go for the simpler 2 part ones.

http://www.unitedchem.com/sitefiles/app ... C-MSMS.pdf

Is this what you are looking for?

Don

Thank you, Don. I am looking for a very fast sample prep (less than 5 minutes), which can produce reliable data and does not require sonication, high temperatures, centrifugation, etc.

Thank you, Don. I am looking for a very fast sample prep (less than 5 minutes), which can produce reliable data and does not require sonication, high temperatures, centrifugation, etc.

Good luck Vlad.

Regards,
Don

I am looking for a very fast sample prep (less than 5 minutes), which can produce reliable data and does not require sonication, high temperatures, centrifugation, etc.

I really don't think you will find such a method for Cannabis, but if you do please let me know as I work with Hops. Cannabis is very similar to hops - they are sisters - both of which contain (to quote a collegue) "promiscuous biosynthetic pathways" for detailed info on these pathways I refer you to:
Kennelly, E.J. et al, Food Chemistry 145 (2014), pp. 254
van Bakel, H. et al, Genome Biology 12 (2011), no. 10, pp. R102

Here is an "out of the box" suggestion - try and freeze out the unwanted components. Amounts and times can vary depending on your application, but its just to give you an idea.
Place 2.7g homogenized sample (finely ground is preferred) and a ceramic homogenizer (or steel ball bearings) into 50mL centrifuge tube. ceramic homogenizer or ball bearings ensure homogeneity during mixing which will improve reproducibility
Add 15mL extraction solvent (100% or acidified MeOH, 100% or acidified Acetonitrile, or some other solvent)
Shake sample for 5 min at 1200 rpm on GenoGrinder
Freeze sample at -40C for 30 min
Centrifuge for 10min at 1000 rpm and remove aliquot for analysis.

A tissue tearor? It is like a little grinder on a stick that macerates your sample. I used it to prepare orange pulp.

A tissue tearor? It is like a little grinder on a stick that macerates your sample. I used it to prepare orange pulp.

I use one of these that looks like it is a Dremel tool with a grinder tip to grind up Broccoli seed meal for analysis. It works well on anything except the whole seeds, for that I crack them first in a mortar and pestle then grind them with the tissue tearror(tissue homogenizer). 2 minutes at 1500rpm works pretty well. We use a mixture of water and ACN for the solvent. It should work well for what you are doing I would think.

All these are traditional techniques and require some kind of knowledge. I am looking for something even easier, that a person in dispensary can weight a sample put it the "cell", press the button, walk away for a smoke (of tobacco), come back to a result

I am looking for something even easier, that a person in dispensary can weight a sample put it the "cell", press the button, walk away for a smoke (of tobacco), come back to a result

Be careful what you ask for. If automation reaches the point where all analyses are done this way, we will be out of work and relegated to having a "smoke" to pass the days

I am not asking about it, we are working on the approach. Seems to me that the hardest art in any analysis is sample prep, since we want to do everything for end user, but cannot be there for the sample prep.

Restek has been working on this-
http://blog.restek.com/?cat=30

It is like a little grinder on a stick that macerates your sample. I used it to prepare orange pulp.

I recall reading many moons ago that canabis leaves contain carbonates that bubble with exposure to HCL. Can't get much quicker than that.

this is not a specific test for cannabinoids as only few of them will generate CO2, in addition to that there are 100 of other compounds in leaves which will decompose to generate CO2