In Home and DIY Testing your Cannabis for THC and CBD Potency

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Here is the thread http://www.marijuanagrowing.com/showthread.php?8730-Test-THC-and-CBD-at-home

Here are a couple excerpts...

Hemp Husbandry

Robert A. Nelson
2000


6.5 ~ Identification

Colorimetric tests are the simplest method of identifying cannabinoids. Hundreds more sophisticated analytical methods have been developed, as a review of Chemical Abstracts will reveal.

The Beam test is relatively specific. It gives a purple color with 5% ethanolic KOH, based on the oxidation of CBD, CBG, etc., and their acids to hydroxyquinones. However, THC does not react to the Beam test. Only two plants (Rosemary and Salvia) out of 129 common species tested give a weakly positive reaction. Among some 50 pure vegetable substances such as mono- and sesqui-terpenes, aromatics, etc., only juglone, embelin, and alkyl dioxyquinone develop a color reaction close to that of Cannabis. The reaction is not always dependable; it can be absent if the ethanol is hot. (22, 23)

A modification of the Beam test uses absolute ethanol saturated with gaseous hydrogen chloride. When added to an extract of suspect material, it gives a cherry red color which disappears if water is added. However, the test also gives more or less similar red color reactions with pinene, tobacco, julep, sage, rosemary, and lavender, etc..

The colorimetric test of Duquenois and Moustapha is not so specific as the Beam test, but it is very sensitive. The test reacts to CBN and CBD, but not to THC:

Vanillin (0.4 gr, acetaldehyde (0.06 gr) and 20 ml 95% ethanol is stored in a bottle. Extract the plant material with petroleum ether, then filter it and evaporate the solvent. Add exactly 2 ml of reagent and 2 ml concentrated hydrochloric acid. Stir the mixture; it turns sea-green, then slate gray, followed by indigo within 10 minutes. It turns violet within 30 minutes and becomes more intense.

The Duquenois-Negm hydrogen peroxide/sulfuric acid test is suitable for following the development of the resin and its potency. Macerate cannabis in chloroform or light petroleum ether for several hours. Evaporate 0.2 ml of the extract in a porcelain dish. Add 2 drops 30% hydrogen peroxide and 0.5 ml concentrated sulfuric acid. Rotate the dish gently, and observe the color of the liquid after 5 minutes. A pink color indicates CBD; blood-red color indicates a high concentration of THC. Violet or strong brown indicates THC. CBN produces a green color which quickly turns green-brown. (24)

The identification of cannabinoids has been made irrefutable by the modern development of gas chromatography, especially when combined with mass spectrometry.

Laboratories which do not possess these technologies can use diode-array and programmable variable-wavelength ultraviolet absorption detectors in conjunction with thin-layer chromatography (TLC) or high-performance liquid chromatography (HPLC), or a combination of both, and make comparisons with published data in conjunction with the specific absorption spectrum for the cannabinoids (200-300 nm). The combination of these techniques can overcome the problem of errors due to interference which often occur when single methods are used. (25)

http://www.hempbasics.com/hhusb/hh6thc.htm
 
I should have everything I need to try this by the end of the week. I have 3 Continuum plants about 4 weeks into veg. According to the writer, that should be enough. He even mentioned that leaves, will show.

So, I'll be trying it by this weekend.

Would be nice if the community would develop some decent quality tests. I can see 'in home' testing becoming a thing. Especially, testing for pesticides.

All in good time. :)
 
What up Bro?
Hey,,i got an old fashion way of testing your Weed,,,send it to me and i will smoke it and get back with your info. :smoke1:
 
Don't laugh, that's how I test my weed now. LOL

I have a few friends that I use for testing dummies for pot, concentrate, edibles, etc. LOL I can't tell one pot from the other except for taste.

However, this is CBD and I'm not sure how it's supposed to make them feel so, how will I know if it's working? LMAO

I'm sure that better and better methods will emerge. I mean, we're all not still smoking out of corn cob pipes and using wheat straw papers. LMAO Things will change, usually for the better. :)
 
Cbd's are very hard to titrate for folks, as there is no way to get too stoned except for you cant walk because you are too relaxed. I think when you're dealing with non-stoners that want cbd so as they don't get stoned but can sleep better, etc it is way hard to tell them to start with 3 drops and see where you end up. I have had thc pot tested for 50 bucks a gram sample. Too much for me to test all these cbd;s I just popped, but just for curiosity.

i think the high we get is an entourage effect. do we need to test for terpine profiles? Fun stuff. Hackerman, fascinating thread, thank you.

One last ramble. my trainer is not a stoner. Her REM sleep was increased by two hours. WHAT?????? Amazing.
 
Well, I'll be a monkey's uncle. This actually works.

I did some experimenting today with that home test procedure and I must say, I am impressed. There are definitely some bugs to work out but I think this method can work very well.

I have enough material for hundreds of tests (all for about $20) so at pennies per test, I am going to run this thing up and down the flagpole.

My first test was just exactly per the instructions and I used a tiny clipping of flower from one of my continuum plants. I trimmed some off of each plant a few days ago and I have been letting it dry to use with these experiments.

The first test was pretty cool. It wasn't even complete and it was already showing purple. At the completion of the test it was a nice dark purple.

Yeah, well, I'm not easily convinced and being the skeptic that I am, I grabbed a little sample of some Cinderella99 I have. Let's see if that shows up purple, too.

As you can see in the first pic, the 2 are pretty darn different.

So, I grabbed samples from all 3 phenos of continuum and ran the tests again. Pic #2.

I'm not sure if pheno 3 is actually weaker than the other 2 or if I mis-weighed something or didn't shake right or, or, or. So many variables in one test.

I am going to run a score of tests on all 3 phenos from all parts of the plants, including stems and leaves and if I consistently get lower ratings for pheno 3, I may actually believe all this. Not sure I'm ready to toss the pheno 3 clones yet but, we have something to work with that's not $50 a test.

So far, this is still a 'has it or doesn't have it' test for me. If I can prove there is actually accuracy in the gradient of color, I'll be surprised. I am thinking it's more because of variances in the test procedure, However, the science is solid and it's actually from patents filed back in the 1940's so, who knows.

I must say, for the few dollars spent and the fun had, it's a great cannabis toy if you're into CBD. LOL

One variable that's hard to control is the weighing of small quantities like 35mg. I had a nice glass enclosed scale at one time but, it was lost in the sea of monsters. LOL The typical scales we (certainly I) use are only accurate to about a 10th of a gram.

I could scale everything up and use bigger vials, more solvent, etc but, it might be smarter to get a better scale. LOL

I am going to be doing a bunch of tests with too much lye, too little lye, shake longer, shake less. just to see if it really is consistent.

Anyway, Like I said, great Canna-toy. LOL

View attachment hometest-1.jpg

View attachment hometest-2.jpg
 
Way to go Hack, so the purple indicate cbd present? And the one that’s not purple is a known non cbd? Interesting...keep up the good research!
 
Yes, the purple denotes the presence of CBD. The more CBD, the darker purple. Those vials are C99, pheno 1, pheno 2, and pheno 3 of the Med Tree.

I have run a few more tests and the pheno 3 keeps coming up short. I even added more weed than recommended, thinking the color would be darker but it wasn't. ???

I can't get into my flower room right now but tomorrow I'll be running more tests.

I was talking to Curt and we're going to see if we can figure which chemicals will do this for THC. CB Scientific does have a THC test that's based on color and uses about the same procedure so we just need to figure what chemicals they're using. Shouldn't take long.

It was nice of him (and people like him) to share this stuff with the community. All this makes me wish I had kept taking chemistry class past high school. LOL
 
Hackerman said:
One variable that's hard to control is the weighing of small quantities like 35mg. I had a nice glass enclosed scale at one time but, it was lost in the sea of monsters. LOL The typical scales we (certainly I) use are only accurate to about a 10th of a gram
Click to expand...

With the resolution you need, the scale will be quite expensive. Used one might be cheaper but would probably need to be calibrated.
A different option would be to use a balance with a known weight. Small piece of aluminum can be filed down to get the weight you need. You can easily make a balance with things around the house. All you need is access to a precision scale to make your weight. Use the same home made weight for all test material and you may get more consistent results.
 
C'mon, this is the 21st century. Everything is cheap. LOL

I almost bought this one for $100 https://www.ebay.com/itm/300g-0-001...441534?hash=item280f10a77e:g:vCkAAOSwLVZVlkOl

but that company didn't have great reviews and this scale actually had better ratings....

https://www.ebay.com/itm/Jewelry-Sc...124589&hash=item1c845332c0:g:yVEAAOSwlndZCxwD

I bought the second one for about $30.

From the tests I have run, quantities don't seem to be critical. That 1mg rated scale should be fine. I also ordered some funnels. LMAO Trying to get all this stuff in that tiny vial is.... LMAO

Here are some early test results........

From left to right....

First is a sample of pheno 1 (the strongest so far based on yesterday's tests). It's a bud from the top of the plant and is mostly pistils and some tiny sugar leaves. This is the best there is and can be the base line for now. Everything is above or (more likely) below this line.

Second from the left is also pheno 1. This is lower buds. Barely developed. Just a few pistils and some real real young bud. This is the same as the next one to the right except I used pellets of carbon in this one and I used granules in the 3rd

Third from the left is as described previously with carbon granules rather than pellets. The granules work better. The carbon granules are there to provide Oxygen.

Fourth from the left is still pheno 1. These are sugar leaves from the flowering plant. Again, to call these sugar leaves is stretching it since it's all from real real low and undeveloped buds and their leaves are barely developed much less have any sugar on them yet. Still, it shows a nice presence of CBD.

Fifth from the left and last sample of this pheno. This is a leaf from a clone of pheno 1. Still in the veg stage and not showing any color at all. Maybe a little yellow, whatever that means.

I was surprised that the very undeveloped bud showed as dark as the very top pistils. There is one variable that could be affecting things. I used dry for some tests and fresh for a few others (the pistil tests were fresh).

I'll redo all the tests to confirm these results. I am going to natural dry some samples first.

OK, the next 3.

These are pheno 3. My worst. Tests on this plant constantly shows poor results.

The first one is the basic undeveloped buds similar to what I used in the previous tests with pheno 1.

The first test shows a very light purple. Compare this to the 3rd from the left in the last test group and you are comparing phenos 1 and 3. Same basic plant matter (undeveloped buds). This also confirms yesterdays tests where pheno 3 was much lighter than phenos 1 and 2 using the same basic plant matter (undeveloped buds).

So, in the next test, I thought I would double the amount of cannabis and I used 70mg of the undeveloped bud similar to the previous test.

As you can see, using twice as much cannabis did not affect the results at all. ??? Almost the same color with twice as much pot.

After continual tests of pheno 3 showing light consistently, I considered mulching the pheno 3 clones and only flowering the pheno 1 and 2 clones.

So, I went back and got some nice pistils from the very top branch. Not off the cola (I couldn't do it LOL) but right below it.

I was surprised to see how dark it was.

With pheno 1, the undeveloped buds showed about the same as the top pistils. On the pheno 3 tests the difference between the undeveloped buds and the top pistils was day and night.

So, more stuff to retest and confirm.

Sure is sweet that each test is only pennies compared to the $10 per test the commercial products are charging. I am going to stabilized the variables and see how consistent I can get the results.

View attachment hometest-4.jpg

View attachment hometest-5.jpg

View attachment hometest-6.jpg
 
Here is a c&p from a thread at ICMag. This home testing thing is getting better and better. Once they get the wrinkles ironed out, it should be pretty easy for us to home test our stuff.

These tests are not intended to replace lab test. More like..... I have 5 phenos of a strain. Using this test, I can (quite accurately) ascertain which one has the most/less CBD and THC and from there, determine what clones to take, etc. Once that's all determined, the plant you select can be sent to a lab for accurate and wide span testing.

I'll bet I've run 100 of these tests already and it's still all under 100 bucks with enough stuff for hundreds more tests. And, through all these tests I continue to get consistent results that pheno 3 has less CBD than the other 2. I'm curious if it shows higher in THC.

Anyway, for those who are interested here's the cut and paste....

DIY THC and CBD testing at home.
I don’t know if most of you guys know about these simple test kits you can make at home, but you can test for THC and CBD cannabinoids at home with some pretty simple lab supplies and chemicals that you can buy on eBay or Amazon for cheap.

These are great tool to have around if you are breeding for a curtain cannabinoids or want to test something you just bought.

These are color indicating tests. You will start out with a somewhat clear liquid and it will change to blue or purple depending on the test. I will talk about this later.

I first found out about these tests when I saw a guy on youtube selling color indicating cbd tests for the home breeder for around $50 for three tests, so I did some research and found out that this was a well known test that was developed decades ago. It’s called a ‘’beam test’’. I also found out there’s another test that’s called ‘’the Duquenois reagent test” and it was developed around 1930 or so. This test is for THC and the government used it for testing the presence of cannabis in general and not for isolating just one cannabinoid. For example: a drug test or cannabis residue, like in a pipe. They found out later that there were other none cannabis compounds that would react to this test and it was not used later. But these tests will be very accurate for us to test the levels of cannabinoids in the bud we are testing because there won’t be any other contaminates. Both of these test kits can be made for pennies each.



Before I get into how the tests are made I’d like to let you know that some of the chemicals used can be very dangerous if not handled properly, so proper safety precautions are needed so as to not get hurt.

Things you will need to protect yourself:

1# Chemical resistant gloves

2# safety glasses

3# have a place nearby to wash in case of a spill or if any chemicals get into eyes. Something as simple as a large bucket of water nearby you can flush eyes or skin off quickly before running to a sink.

4# all of the chemicals used in this experiment can be washed off or neutralized with water just in case you need to in a emergence.

5# do not use anything metal when performing this experiment! A violent reaction will happen!!! No metal tools or containers can be used, only plastic, glass, rubber can be used….

6# if you don’t really know what these chemicals are don’t try and mix any of them other than the ones I say. Lye is very alkaline and hydrochloric acid is very acidic, mixing them would not be good.

7# Use caution when storing these chemicals. Keep them away from people that don’t know how to use them, it goes without saying it, but I’ll say it anyway. Keep them away from children and pets!

8# do these experiments only in a well ventilated room.

Bottom line is, think first and don’t be stupid!



Ok now that that’s out of the way, on to the fun part! I’ll start off with how you make the extract out of the bud you will be testing.

Things you’ll need:

1# A scale. I think we all have one of these lying around. One that can weigh very small amounts like tenths of a gram or one hundredths of a gram.

2# small plastic or glass jars to mix in

3# 1 or 2ml dropper

4# 100% alcohol/ethanol or as close as you can get. 90% rubbing alcohol will not work it has to be higher than that. 95% or higher. You can buy denatured alcohol at the hardware store.

5# An oven. I like to use a cheap toaster oven so as to not make my kitchen oven smell like ****. But do what you want.



The first thing you’re going to do is take about 1 gram of the bud to be tested and place it in a piece of aluminum foil and fold it over and then fold all the edges closed.

Place the bud and aluminum foil in the oven for 30 minutes on 220f/110c. let cool.

Take your crispy bud out of the oven and weigh out ½ gram or .5000 on the scale in a small jar or shot glass. Now get your dropper out and put 5 grams of alcohol in the glass with the bud and mix well. Let that sit for at least one half hour then suck the liquid out and put that in another jar or glass without getting any bud material in the glass. That is your extract you will be testing.



The first test will be the Duquenois reagent test. This is for testing THC.

There are many ways to perform this test; this is just my modified version of this test. The original test called for chloroform to be used to stabilize the mixture and separate the organic layer. But chloroform is some nasty ****. This is the stuff the Nazi’s used to kill countless people. It’s very gaseous and is a silent killer when working with it. I also don’t like buying it for obvious reasons. It can be made with bleach and acetone easily if you know what you’re doing.

Things you’ll need:

1# Glass test tubes or shot glass

2# a dropper

3# hydrochloric acid 37% or higher

4# vanillin which is a synthetic vanilla

5# 100% ethenol

6# amber glass bottles with dropper built in if you want to store the reagent for later use.



We will be making the reagent first.

Weigh out 5 grams of vanillin and dissolve that in 100ml of alcohol then put in amber bottle. That is your reagent.

Get a test tube and place three drops of your cannabis extract in the test tube followed by ten drops of reagent. Mix well. Now carefully put 10 drops of hydrochloric acid in the same test tube with your reagent and extract. Mix well and wait for color change. This may take up to thirty minutes to get to its full color.

You should see a deep blue or royal purple to black color for a high THC strain and light blue or purple for a low THC strain. Little to no color change or off color means very little to no THC.

This test is best used when comparing two strains side by side or two phenotypes of the same variety so you can see the difference in color to know which one has more THC. (darker=more THC), (lighter=less THC).

I have found that One turned purple and one turned blue which can make it difficult to compare them so I just looked at how dark the colors were. In cases like this it’s best to have a known variety that you can compare to, but most of time you will get purple as your main color.






The beam test: This test is for CBD.

Things you’ll need:

1# Glass test tubes

2# a dropper

3# 100% alcohol

4# potassium hydroxide (AKA) Lye

Dissolve 5% lye into ethanol which is five grams of lye to 100ml alcohol. Mix well.

Grab a clean test tube and put three drops of extract into the test tube followed by 10 drops your dissolved lye, mix well. You should see a pink to purple color in the presence of CBD. It may take up to thirty minutes to see any color change. Pink is low CBD and purple is higher CBD.

I don’t have any CBD samples at the moment to show you, but you will get the same purple color as the THC test.

You can also play with the concentrations of the mixture or concentrate the extract by striping the ethanol and make the test more sensitive for very low THC and CBD.

And, here's a link to the post, in case you want to see the pictures or follow the thread....

https://www.icmag.com/ic/showpost.php?p=8180934&postcount=2
 
Just FYI, I finally received my supplies and these tests really work. CBD and THC.

Tests consistently show similar results. There is going to be a curve while all the little bugs are being worked out but I am running these tests right now and getting great results for only pennies per test.

The Continuum is showing very very high in CBD and almost zero THC. A Cinderella99 sample and some other high THC strains are showing high THC and no CBD.

I wish I had a 50/50 strain to test.

I am going to start running tests on e-juice and rosin to see if I can get some consistent results. Would be awesome to be able to make an edibles test.

Anyway, just thought I would update you to let you know that home testing for pennies is right around the corner for everyone.

View attachment funk.jpg
 
OK, gang. It's done, smooth and the wrinkles are ironed. LOL

If anyone want to try this I am more than happy to walk you though it.

There are a couple things that need to be purchased on ebay or Amazon because they are not likely available locally. However, much of the stuff is readily available.

Amazing how accurate it's starting to get.

For THC tests, the Vanillin is available online but the denatured alcohol and muriatic acid come from Home Depot.

For CBD the NaOH or KOH is an online buy but the alcohol and carbon are usually available locally.

Couple glass vials, some rubber gloves and safety goggles and you're on the road. LOL

Pretty neat, for sure. And, like I said, very accurate in terms of a home test. Not as good as HPLC or Spectrography but I'll bet it's as accurate as TLC. And, cheap.

Next project is sexing plants by extracting DNA and viewing the chromosome chain for the big Y.

All that's needed here is some home chemicals (salt, etc) and a 2000x microscope that can be had on eBay for $200 to $300. Figures that I sold mine last year. LOL
 
Just a heads up for you people growing CBD strains. The tweaking is done on these tests and they are working like a charm. I get a nice light to dark gradation using different strengths of samples. I don't want to put percentages to it but some of the other people have compared their results to lab tests and are starting to make color/potency charts. Quite frankly, as a home grower, I don't need any more info that what I'm getting. I don't really care about 10%, 20%, 30%. I'm OK with high, medium and low. LOL You can definitely tell one plant from the next. That's all I need.

The denatured alcohol can be purchased anywhere locally. Home Depot, etc. DO NOT BUY ANYTHING THAT SAYS GREEN.

The GREEN stuff is just diluted and won't work. Same goes for the alcohol and muriatic acid.

The reagents will have to be bought online. KOH is Potasium Hydroxide. And Vanillin is artificial vanilla flavoring. Again, do not buy drain cleaner and vanilla flavor. These need to be lab grade 90%+ stuff.

I bought a pound of KOH on eBay for about 10 bux. It's a pretty small package and should last me for years.

The Vanillin is the same. About 10 bux for an 8 or 10 ounce bottle. Enough for a lifetime.

If you need help on what to buy before you buy it, put a link here and I'll tell you if its the right stuff.

I don't know how you guys are going to breed CBD plants without this test.

And, the THC test as well. I know some of you wanted high CBD and no THC for your friends. These tests tell you in minutes.

Albeit, smoking it will work too. LMAO
 
I think it’s a great idea but I also think it will take further experimentation to define the results. In other words use some of the tested plants so you can see what they do for you. Then you’ll be able to relate those results and know more about what they mean and help yourself to more consistent grows.
 
It's so easy to do Rosie. You'll want to be doing it all the time. Once you do it, it's fun.

All you do is put some pot in a shot glass or glass vial and add the alcohol. This extracts the trics from the plant matter.

Then, mix some KOH and alcohol in a small vial.

Take 3 drops of the alcohol extract and add to it, 10 drops of the KOH mix. That's it.

Pretty simple.

You would use the same precautions you would use whenever using alcohol or drain cleaner. Not a big deal.

Are you an Amazon or Ebay person? Which one? I'll post a couple links to the KOH. The denatured alcohol is at Home Depot.
 
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