Do anybody have experience with these THC / CBD tests?

[Rowz74]

I got a very special pheno I think its high on CBD and looking for something to test

Do anybody have experience with these test


http://www.ebay.com/itm/Cannabis-TH...006046?hash=item4aff40a31e:g:vXUAAOSwx-9WwmP3

 

[corky1968]

I've never used any THC-CBD test kits before.

But I have looked at the ones made by these company a few times.

Looks pretty good too.

http://www.cannalyticssupply.com/

Cannalytics User Manual PDF

 

[Chimera]

it's called thin layer chromatography. It's really only useful for distinguishing between plants with THC only, plants with a mixed THC/CBD chemotype, or plants that are CBD only.

Despite any claims by the seller or manufacturer, you can't quantify compounds using TLC, you can only detect their presence.

If you are simply looking for the presence of CBD, and not distinguishing between pure CBD and mixed THC:CBD plants, you can use the Beam test which does not need the kit, just a few items you can get from the grow store or from Amazon or Ebay.

Search "Beam test" on icmag and you should find a thread detailing the process.

Hope that helps,
-Chimera

 

[corky1968]

it's called thin layer chromatography. It's really only useful for distinguishing between plants with THC only, plants with a mixed THC/CBD chemotype, or plants that are CBD only.

Despite any claims by the seller or manufacturer, you can't quantify compounds using TLC, you can only detect their presence.

If you are simply looking for the presence of CBD, and not distinguishing between pure CBD and mixed THC:CBD plants, you can use the Beam test which does not need the kit, just a few items you can get from the grow store or from Amazon or Ebay.

Search "Beam test" on icmag and you should find a thread detailing the process.

Hope that helps,
-Chimera

You sure about this inability to quantify with TLC?
Maybe not with these over the counter kits. But it
seems doable by TLC by scientists according to the
following links.

Comparative study for the quantification of THC, CBD and CBN....using alpha-CAT TLC method and GC-FID

This following PDF is interesting with it's OPLC method.

SEPARATION AND IDENTIFICATION OF CANNABIS COMPONENTS BY DIFFERENT PLANAR CHROMATOGRAPHY TECHNIQUES (TLC, AMD, OPLC)

 

[Chimera]

You sure about this inability to quantify with TLC?

Yep, TLC is qualitative, not quantitative.

Maybe not with these over the counter kits. But it
seems doable by TLC by scientists according to the
following links.

Comparative study for the quantification of THC, CBD and CBN....using alpha-CAT TLC method and GC-FID

This following PDF is interesting with it's OPLC method.

SEPARATION AND IDENTIFICATION OF CANNABIS COMPONENTS BY DIFFERENT PLANAR CHROMATOGRAPHY TECHNIQUES (TLC, AMD, OPLC)

Even these authors say its semi-quantitative. ie, you can get an approximation, but it's not truly quantitative. Also keep in mind that these Spanish authors also performed the experiments using a lab, with proper weighing and careful sampling This is really not common in home use.

The first thing they teach you in Chemsitry is that TLC results are really only qualitative, not quantitative.

I'm not saying TLC is not useful, it just isn't accurate. If you have run as many samples as I have using GC and HPLC and TLC samples, you'll know that there is no real quantitation using TLC. Your second link also states that you can separate identify compounds, but doesn't say you can accurately quantitate.

 

[corky1968]

I'm starting to think that really accurate tests are not available to the average person without scientific credentials.

 

[GoatCheese]

Beam Test

Beam Test

The needed reagents are:

5% KOH(Potassium hydroxide) in 95% ethanol
(5g KOH in 100 ml 95% ethanol)

Petroleum ether, Naptha or other organic solvent to remove the cannabinoids from a sample of your choosing.

Place 1-2 grams of your sample flowers in an oven until dry @ 150 degrees Celsius for 5 minutes. Extract in a small glass vessel (shot glass?) for 10 minutes in 10 ml of your Petroleum ether, other organic solvent, naptha, etc.

Filter and remove the leaf material using a coffee filter or similar, catch the liquid extract

Take 1 ml of the extract and dry on a white porcelain dish like an egg cup, saucer, or similar. (Gently heat the dish to evaporate the liquid phase of the extract). You will have a dish with remnants of resin leftover once the liquid has evaporated.

Place 5 drops of your 5% KOH in ethanol solution on your plate, and wait about 10 minutes. You will see a distinct violet/purple/pink color from samples containing CBD which could be Chemotype II or III plants - in the case of CBD Lullaby they will be only Type I and II plants- THC only plants (chemotype i) will not show this colour.

It's a relatively simple test and anyone can do it, you just need to order KOH from Amazon or your local soap making store and pick up a solvent from your local hardware store. The ethanol will probably be the most difficult thing to source, but it is available as "Everclear" or 190 proof ethyl alcohol from your local provincial or state run liquor store, depending on your location.

Hope that comes in handy....
-Chimera

Found this by accident at Mr Nice forums.


Thanks for this, Chimera!

 

[Rowz74]

i think they got some chemics to charge the cbd or thc content, at more intense color more cbd/thc got i think how is that work.