Standards Used in Testing

[plastochron]

yea i've spent about as much time kicking myself about not paying enough attention during stats as i have spent relearning different techniques as needed. within a 1g sample there can definitely be a significant different in CB concentrations... occasionally dispensaries will send us samples of B buds that they would rather test than sell and after they are disappointed with the results they will resubmit a cola sample; the difference between the two results have been as much as a 30% (i.e. 15% vs. 20%).

are you in norcal by any chance? if so just wondering what lab you patronize.

 

[KiefSweat]

I'm in CO, and patronize them all
I'm trying to find the best one to work with, but got some nerd friends who would love to run a gc for me.

 

[KiefSweat]

i should say my first test seems to be going well

I should have figured this out before I started but thats not as much fun.

I tested some hash oil solution last week. So I extrapolated those numbers and evaporated a measured solution. The goal was to get at least that number. (there is going to more then thc in oil) I now need to get a good total number including some loses on the return of oil.
I can take that number and get a rough estimate of what the test on the oil should come back at tomorrow.

 

[KiefSweat]

ok so that didn't work so well.

Got much more then I would have expected which on paper would mean its like 58% thc. I know from testing a similar process elsewhere and comparison to other extracts that that number would be too low, especially when comparing to that labs other published data,

so this brings me back to the same issue I am having, I think that a large sample size needs to be tested. Mabye 1oz of solution at each place if I was to go that route. But testing a few mls I think leaves open to much room for variation.

So I suppose next goal is testing the extract. 2 of the labs can give me numbers for the acidic and free cannabinoids, the other can only give me a total.

 

[plastochron]

KS, my apologies if you went into details about this earlier in the thread, but what is your extraction technique? how many compounds can your GC buddies identify at this point?

 

[KiefSweat]

Making absolutes., I've had some test around 76% thc.

Depends on the lab.

One of them tests for THC-A, THC, CBD-A, CBD, and CBN -hptlc setup
the other has 2 setups. I think they do the above as well as THC-V - they have a hplc and a gc that they are setting up a mass spec on now.
the other lab with GC, just does, THC, CBD, CBN and THC-V

 

[plastochron]

are any of the labs in CO analyzing terpene concentrations?

how much variability have you seen in the results? if you calculate for inefficiency of decarboxylation are the LC results + the same as the GC results?

 

[KiefSweat]

no terpene testing yet.

I've seen a 25% range or so between labs.

I dropped of some samples this week but the thc-a sample as degraded and they need to get a new one to recalibrate the machine. They are supposed to run a sample on the gc for a comparison for me.

 

[plastochron]

full spectrum is no longer around, correct? their website looked very proper. did you ever use their services? how did they stack up to the rest of the labs?

 

[KiefSweat]

dealt with FSL a few times. One of their employees is still around, and I still work with him.

When I starting working with them is when they starting shutting down operations really so don't have much to compare.

Its been quite the experience being able to test some of my theories. Sometimes its tough as the lab operators see things from a different aspect so it helps to have an understanding of what I am doing to be able to analyze the whole process.

Its really starting to grow as a service here, and its really exciting to be a part of it and see it organically evolve.
I would love to have accesses to some of the data the labs have collected, not sure what I would do with is, but some of them must have quite the database with 1-2 years of work.

 

[plastochron]

well if you have specific questions that i might be able to address or compile a bit of data i would love to help (as long as it doesn't get me fired )

 

[Sam_Skunkman]

CBD/CBC separation in an analysis is easy with a GC if you have two columns and two injection ports. You use the longer column for CBD/CBC separation. The other column for all the other Cannabinoids.
The GC can switch between columns anytime as needed. So load a sample tray with 96 samples and let them run using one, or two columns.

-SamS

 

[IncredibowlBoss]

Amazing thread - especially as lab testing sets the MMJ industry standard (and is even weighted heavily in High Times cup judging), this discussion NEEDS to happen in a public forum with exactly the sort of informed, educated, and experienced individuals who are participating (THANKS, Sam - your input is priceless, as always!)

full spectrum is no longer around, correct? their website looked very proper. did you ever use their services? how did they stack up to the rest of the labs?

@Plasto - I can't personally speak to FSL's accuracy, but I know at least 3 trusted associates who have sent identical samples marked with different names and had variance as high as 15% in all cases. I've seen similar things happen with the other labs out here in CO, as well.

This does lead to a question, though: presuming the tests are *not* 100% accurate, do their results scale in terms of ratio; that is - if a sample tests as having twice the THC of another sample, regardless of the percentage quoted (which may or may not be accurate), can the relative difference between the samples be trusted?

While we're on questions, one for the actual scientists among us:
I've heard that glycerine extractions dont yield themselves to accurate GC/MS, but have never been able to get anyone to follow that statement up with an explanation as to why. So, two-parter: 1. Is this true? 2. If so, why?!

 

[KiefSweat]

While we're on questions, one for the actual scientists among us:
I've heard that glycerine extractions dont yield themselves to accurate GC/MS, but have never been able to get anyone to follow that statement up with an explanation as to why. So, two-parter: 1. Is this true? 2. If so, why?!

over-saturation. Glycerine holds about 10-15mg/ml over that it will come out of solution as a bead of hash oil. not sure why this happens but it does screw up the test results. I've given up on using it as a carrier.

my one test with glycerine came back at like .00056mg/ml or something stupid like that. But damn did 2ml get you high!

 

[IncredibowlBoss]

over-saturation. Glycerine holds about 10-15mg/ml over that it will come out of solution as a bead of hash oil. not sure why this happens but it does screw up the test results. I've given up on using it as a carrier.

my one test with glycerine came back at like .00056mg/ml or something stupid like that. But damn did 2ml get you high!

Thanks for the explanation - if you're from CO, you've probably seen Nancy B's CBD syrup; I've seen SO many patients that swear by it, but when a competing company ran it through a lab, it yielded negligible results - the lady behind the syrup had asked me how that could be, and I was STUMPED!

 

[KiefSweat]

i got similar results with a glycerine tincture from the same lab. I was a bit surprised when i saw that test for the syrup as it was so low on all levels.

surprisingly enough it was one of the owners of another lab in conversation who mentioned the fact about glycerine to me.

 

[elmanito]

Is the syrup never be tested for CBDA????

Namaste

 

[IncredibowlBoss]

i got similar results with a glycerine tincture from the same lab. I was a bit surprised when i saw that test for the syrup as it was so low on all levels.

surprisingly enough it was one of the owners of another lab in conversation who mentioned the fact about glycerine to me.

Just talked with Nancy Bs & she mentioned that the folks at OrganaLabs suggested they do a hexane wash of the syrup and then test the result, but I wonder if that could have any effect on the final accuracy - the only way I could imagine it working is with proper chain-of-custody on the samples, so that a lab performs the wash (rather than the company/manufacturer/grower/etc. sending the sample in) and certifies the sample before sending it on for testing. Any thoughts?

 

[KiefSweat]

Just talked with Nancy Bs & she mentioned that the folks at OrganaLabs suggested they do a hexane wash of the syrup and then test the result, but I wonder if that could have any effect on the final accuracy - the only way I could imagine it working is with proper chain-of-custody on the samples, so that a lab performs the wash (rather than the company/manufacturer/grower/etc. sending the sample in) and certifies the sample before sending it on for testing. Any thoughts?

I assume they are extracting direct into glycerine then?

the labs as far as I know don't actually understand the extraction process or extract anything themselves.

my first step would be testing my raw starting material to establish that cbd baseline.

 

[KiefSweat]

oh more fun out here Mile-High.
This is a question for those with hands on experience or info. How easy is it to get a 99% pure sample? even 95%. I understand some of the chemistry involved. But if proper lab techniques are not used is anything over 90% pure possible at home?

And in order to make an assessment as such on purity with a botanical matter with so many chemicals what type of assay panel would need to be conducted to conclude that purity?