Standards Used in Testing

[KiefSweat]

Out here Full Spectrum asked for a Schedule 1 license...they were swiftly raided by DEA.

FSL tried growing their own or something too. But they wanted to be more then just a 3rd party tester.

 

[Sam_Skunkman]

Quick note,
Altho I do not live in the USA, researchers in the USA tell me that almost all Cannabinoids are available without DEA license, in very small amounts, but enough for GC calibration. If I remember Cayman and ELI as well as several others sell them.
http://www.elsohly.com/stds_intstds.html

I would be surprised if any lab is testing for all 130 terpenes, but they will sooner or later. I have found a half dozen other terpenes that are not in the published literature, so at least 135 and still counting....

As for GC calibration I use Hewlett Packard. I can say that when done correctly, all three labs in three different countries gave basically the same results for several samples with a variance rate of less then 1% so we might get 10% THC, from one, 10.4 from the next, and 9.8 from another, some times we did get the same at all 3 labs, ours included. The differences were a few tenths of one percent, in the case of Cannabis with 10-20% THC.


-SamS

 

[KiefSweat]

as far as I know no labs in this state are doing terpene testing.

Just mold/tox screens too if asked.

 

[GreenintheThumb]

What about Industrial Labs in CO? I thought I read they were setting up testing. They've been around forever and used them for some conventional product testing over 10 years ago.

AFAIK they have never tested cannabis. I don't think legally they can right now. However, they have the means to get into this industry and perhaps they will after the rules are promulgated surrounding lab licenses for cannabis. Right now most of the labs testing cannabis are operating under an MMC or MIPs license, and it's my understanding that IL didn't acquire either. Like I said, I can see that changing as proper lab licenses are handed out (maybe in 2013, hahah) as these folks have the proper facilities and manpower to do it right. Time will tell.

 

[mofeta]

I have found a half dozen other terpenes that are not in the published literature, so at least 135 and still counting....
-SamS

^^^PAY ATTENTION TO WHAT THIS GUY HAS TO SAY^^^

That quote from Sam is no idle boast. As far as I know, there is no living human being that has more knowledge on this subject. He is the only PRIMARY source of info that posts on these boards. He doesn't just read primary sources like the rest of us, he WRITES them. The leaders in the scientific inquiry on cannabis consider him a colleague and peer. This is a very rare accomplishment for an amateur, and a testimony to his passion, perseverance, and intellect. We are unbelievably lucky to have him contribute here.

THANKS SAM!

 

[mofeta]

For those of you looking for reference materials, there are plenty of places on the internet that offer them. Here are a couple of examples:

Sigma-Aldrich

THC Pharm

Sam also mentioned Cayman and someone else.

Most of the companies offering reference cannabinoids cater to forensic (police) customers, so they offer lots of standards for the metabolites that can be found in a human that has consumed pot. Some that specialize in serving researchers carry standards for the less well-known cannabinoids, maybe refine your Google search with the term "phytocannabinoid", to specify compounds found only in the plant.

Recently, some companies offer deuterated (a way of marking compounds) which allows you to use a standard for the analyte(s) of interest as an internal standard.

For those of you interested in GC techniques, I suggest you read the book that G.O. Joe linked to upthread. For those of you who have a good grasp of GC in general, and are more interested in cannabis specific protocols, look for papers about the cannabinoid profiles of various types of herb like this one:

A chemotaxonomic analysis of cannabinoid variation in Cannabis

Then check out the "Materials and Methods" section to find stuff like this:

Sample preparation for GC analysis
Cannabis plants were grown in two secure greenhouses at Indiana University, Bloomington, Indiana, USA. The plants were individually grown in 13-cm clay pots in a soil mixture of three parts (by volume) black peat, two parts vermiculite, and one part each of sand and top soil. Each plant received 100 mL of nutrient solution at weekly intervals during the vegetative period of growth, consisting of 25 mL of Dyna-Gro 7–9–5 (Dyna-Gro Corporation, San Pablo, California, USA) and 18 mL of 1 M potassium hydroxide (to neutralize the acidity) per 3.8 L of water. Pistillate plants were isolated from staminate plants before anther dehiscence. The inflorescences of pistillate plants were sampled when resin production of each plant was visually assessed to have reached its peak. The samples were air dried at room temperature and oven dried overnight at 30°C prior to extraction. The primary and larger secondary leaves were removed, and only visibly resinous floral bracts and small subtending leaves were analyzed.

Sample extraction
Sample material (50 mg) was placed in a test tube with 1 mL of chloroform. The plant material was crushed with a glass rod and briefly sonicated to dislodge and/or rupture the resin heads of the glandular trichomes. The sample remained in the solvent at room temperature for at least one hour, and was sonicated again for a few seconds. A 20-µL volume of extract was transferred to a small test tube, and the solvent was evaporated with a gentle stream of nitrogen. The residue was redissolved in 50 µL of acetone containing 0.25 mg/mL of n-eicosane, the internal standard.

GC conditions
Chromatograms were generated with a Hewlett-Packard 5710A gas-liquid chromatograph fitted with a 30 m x 0.53 mm DB-5ms column (J & W Scientific, Rancho Cordova, California, USA) having a film thickness of 1.5 µm. Injector and detector port temperatures were 250°C and 300°C, respectively. Carrier and make-up gas flow rates were 5.8 mL/min (He) and 24.2 mL/min (N2), respectively. The temperature was held at 200°C for 8 min, then increased to 300°C at 4°C/min and held for 4 min. The integrator was calibrated with single concentrations of CBC, CBD, CBG and THC at 0.5, 0.4, 0.5, and 0.4 mg/mL, respectively.

If you do it like the quote above, you will get the kind of quality results Sam does! (assuming you are already a competent GC technician, lol)

Here is another source of information for you guys, it is a guide prepared by the United Nations on testing Cannabis, it has some good info, but it is also pretty entertaining! (you will see what I mean, do you think these guys surf ICMAG? lol):

Recommended methods for the identification and analysis of cannabis and cannabis products


Pay attention to the part about how to deal with the acids like THCA by derivitization/silylation if you are interested in these compounds, as the chromatograph's oven will decarboxylize them and you will only have total THC (or CBD or whatever) in your results.

Good luck!

Edit: I don't buy any reference materials, and don't know about obtaining licenses, watch lists, or which overseas suppliers send to the US, so I can't help you with that. Sorry.

 

[KiefSweat]

http://www.tokeofthetown.com/2011/09/how_accurate_is_cannabis_testing_ring_test_assesse.php

http://www.canorml.org/RingTestOShaughnessys_Aut11.pdf

 

[KiefSweat]

Pay attention to the part about how to deal with the acids like THCA by derivitization/silylation if you are interested in these compounds, as the chromatograph's oven will decarboxylize them and you will only have total THC (or CBD or whatever) in your results.

GC machines run at 200c+ Hence why you just get one reading from it. HPLC machines run at room temp.

 

[highonmt]

Quick note,
Although I do not live in the USA, researchers in the USA tell me that almost all Cannabinoids are available without DEA license, in very small amounts, but enough for GC calibration. If I remember Cayman and ELI as well as several others sell them.
http://www.elsohly.com/stds_intstds.html

I would be surprised if any lab is testing for all 130 terpenes, but they will sooner or later. I have found a half dozen other terpenes that are not in the published literature, so at least 135 and still counting....

As for GC calibration I use Hewlett Packard. I can say that when done correctly, all three labs in three different countries gave basically the same results for several samples with a variance rate of less then 1% so we might get 10% THC, from one, 10.4 from the next, and 9.8 from another, some times we did get the same at all 3 labs, ours included. The differences were a few tenths of one percent, in the case of Cannabis with 10-20% THC.


-SamS

All right here goes, I am a professional organic chemist and there are a few points sam makes in this excellent post that need clarification. First, it is true one does not need a DEA license to buy common drug testing samples. The samples you can legally purchase are micro gram quantities dissolved in acetonitrile or other organic solvent or aqueous /organic solvent system depending on the solvent system you are running, the poperties of theanalyte, and the column packing material you are using. These samples are normally provided in glass ampules. Purchasing the parent compound and preparing samples yourself would require a license. The companies that provide these prepared samples are for the most part staffed by competent chemists who use highly purified compounds and dilute them according to accepted procedures, failing this they would quickly be put out of business.

A properly calibrated run on a gc or most other analytical chemistry apparatus will produce repeatable results within error bars. The variability inherent in these systems are of course products of sample variability, sample preparation including the efficiency of the extraction protocol, and the inherent error present in the instrument itself and the fallibility of us humans. A point here is that the plant material itself never gets near the column...the organic or aqueous extract of the plant does and this extraction is NEVER perfect.

THC and all the cannabinoids in cannabis are TERPENOID compounds and are biosynthetic products of geranyl pyrophosphate a common terpene.
There is no one who provides analytical samples of the minor terpenoids that I am aware of, the cost of a complete set would be prohibitive to all but well funded research labs.

I suspect that most of the error incurred in the analysis of cannabis products resides in the preparation of samples not in the standards used. Extraction of organic soluble products from a complex sample like plant material has all sorts of room for errors. Headspace techniques included. If you have a question about the quality of your standards most companies will gladly provide nmr, ms, hplc traces etc to assist you.
HM

 

[Gray Wolf]

Any thoughts on who makes the best GC unit for this application?

 

[Dkgrower]

I suspect that most of the error incurred in the analysis of cannabis products resides in the preparation of samples not in the standards used.

 

[KiefSweat]

i saw on another forum, A lab in Cali that is doing terpene testing.

Looked like it was about 20 different ones, and most of the samples tested had 35-50mg/g of mixed terpenes.

 

[Green Supreme]

I would suspect, if Sam has chosen Hewlett-Packard she must be a good unit. Peace GS

 

[highonmt]

I would suspect, if Sam has chosen Hewlett-Packard she must be a good unit. Peace GS

They are indeed good instruments however a gc is really quite a simple apparatus just an oven, a coil filled with packing and a detector, The quality of the components, software and the name brand add to the price.
This is a well constructed system for a good price that is set up to do major cannabinoid profiles and pesticide profile as well as an option
http://www.srigc.com/MedicalMarijuanaPotencyGC10-10.pdf
Our company uses this system too meet some of the testing requirements of the states we operate in. Very simple no inert gasses required has an air dryer and compressor built in. Very simple and gives decent results imo , not ideal but 12 grand and you are set up for thc, cbd and cbn software included. Not a good idea if are looking for extreme accuracy or analysis of complete terpenoid profiles but perfect for the scientist on a budget.
HM

 

[GreenintheThumb]

i saw on another forum, A lab in Cali that is doing terpene testing.

Looked like it was about 20 different ones, and most of the samples tested had 35-50mg/g of mixed terpenes.

Interesting, can you share that lab?

 

[KiefSweat]

not sure if i can link to the other site here
was the werc shop

 

[highonmt]

not sure if i can link to the other site here
was the werc shop

Nice website, Liquid chromatography service. The say that they offer terpene analysis but no details. I don't think posting the link will conflict with the rules here, If so would a moderator please pipe up...http://thewercshop.com/services/cannabinoid-profiling-services/

This is a really cool analysis you posted my friend. I bet due to the the limonene, valencene, beta-caryophyllene [binds selectivly to cb2 btw]content high the strain must have a real complex citrus smell and taste with a black pepper spice. Probably pretty pest resistant with the significant conc. of germacrene. Let me know if this is the case.HM

 

[KiefSweat]

it was not my test, so I can't comment.

But that analysis is what is amazing about this stuff. To know that certain constitutes will have certain flavor profiles or even other benefits to the plant or user.

Amazing stuff

 

[Sam_Skunkman]

I used HP because it was suggested to me by researchers I knew.
It also allowed simultaneous two injection ports with different columns to allow separation of CBD from CBC, that and an autosampler tray for samples to be injected that holds 96 samples, to be run over night.
Compatible with GC/MS and a head space auto sampler.
And HP service.
-SamS

Any thoughts on who makes the best GC unit for this application?

 

[Gray Wolf]

I used HP because it was suggested to me by researchers I knew.
It also allowed simultaneous two injection ports with different columns to allow separation of CBD from CBC, that and an autosampler tray for samples to be injected that holds 96 samples, to be run over night.
Compatible with GC/MS and a head space auto sampler.
And HP service.
-SamS

Thanks for the input brother Sam! I like HP equipment too and am in fact typing this on one!

Alas, I'm also on retirement income these days too and so always looking for "such a deal". Local testing gets prohibitive fast, and it doesn't take long to amortize out the cost of our own machine, so I've been trolling for a good deal.

Since broaching the question, I seemingly successfully bid on a used Perkin Elmer 8500, ostensibly fully operational with software and manual.

Any of ya'll have any experience with one of them?