Testing for THC

Is there any relatively inexpensive way to test for actual THC content? All of the ‘testers’ I have found on the web are for testing job-related urine samples. These are simple positive/negative results, not an accurate measurement.

A half-century ago, I was a chemistry major and lab tech at a big-city hospital. I was used to using very sophisticated - and expensive - analysis equipment. This year, I grew four different strains, and I am curious about actual potency. (Yeah, they are all very good…) But I’d like to know just how good, which lived up to the hype, and I don’t happen to have ten grand lying around for a good, used gas chromatograph.

This might be a good business opportunity - if you happen to have a spare ten grand…

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Hey @Newt is this the brand you use?

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Google THC Potency test
keep the 10K

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It is. And if you get it from tcheck dot me, you can use code Check15, for 15% off.

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Mind you, there are two versions of the T-Check 2 kit. The $300 one does clear extractions, while the $400 does buds.( I think that the difference is the nifty grams scale.) When doing a quantitative analysis, you need to know precisely the volume - or weight - of the sample being tested.

I recall a little test kit for weed circa 1969. It was in a small plastic box, much like a soil or pH test kit, in that it was colormetric. It included a solvent, a reagent and a stain, and could tell you if your stash was great, or Mexican ditch weed… or oregano. With full legalization and retail sales, I can see that an independent testing service might be a profitable side-hustle.

The add-on adds:

  • – Scale
  • – 1 100 mL bottle of reagent
  • – 10 .22um filters
  • – 1 10 mL syringes
  • – 10 1 mL syringes
  • – 3 sample containers
  • – 3 concentrate spoons
  • – 1 Swizzle stick
  • – 2 AAA batteries
  • – 1 Getting Started Guide

But all you really need is a precise scale, a syringe, and filter and re-agent grade 99.9& isopropyl, Nothing in the expansion kit is special, and can be had from the place that used to be an on-line book store. :wink:

(Which is where I get my consumables - reagent, syringes, and filters)

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@72Rover

I am a retired chemist myself. I have been thinking about THC testing myself and scour the reused equipment sites. Best to you.

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Where is this used equipment site :thinking::crazy_face:

I don’t smoke so I just ask my smoker friends to test it for me.so far no complaints.
Wish I did know the thc content of my grows.

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LabX is one but there are also government and state auction sites.

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I’ve done several web searches on THC potency testing, all of which returned kits and such. None mentioned the actual methodology. The T-Check 2 appears to use a colorimeter; the lower priced one is for extracts, which can work by volume. The higher priced one is for actual weed, with filter paper included after solvent extraction. I could probably build my own - if I knew what solvents or reagents were involved. Newt mentioned 99% isopropanol which would be the solvent. In the hospital, we used to use USP-grade ethanol by the drum. 95% was used for rinsing lab glassware; the 100% (200 proof) ‘absolute’ ethanol was used as a solvent. Untaxed, it was cheaper than milk…

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I just take mine down to the local hydroponic shop to have tested. Typically charge 20 bucks but I just threw them a little handful of bud for helping me through my first grow anyway. They didn’t charge me a dime .

I test mine the old fashion way. No numbers i use more of a 1 to 10 scale of my personal thoughts on smell, taste and buzz. Plus i usually ask a couple friends their opinions. So far the best stuff ive grown i would give an 8. Always room for improvement.

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By all means, get one of these testers if you want. But it may be money not well spent.

All testing equipment needs to either have reference to a constant (like the speed of light for example) or be calibrated (ie: compared) to a known reference point - another tester or material of known spec. The later is typically how you would calibrate your PH pen.

I don’t know the specifics of these testers but unless they come with a calibration cert or some sort of reputable endorsement, the number it gives could mean anything.

Here is a better bang for your buck

Excellent… How much was the kit? A half century ago when I was a lab tech in a big hospital, I typically used electrophoresis to measure serum proteins, hemoglobin types and cholesterol levels. Spent a full summer doing research using chromatography to predict Schizophrenia by using patterns of amino acids. It was pretty cool, except for the solvent, pyridine, which is the nastiest-smelling stuff on the planet.

I’ll check out the kit… Thanks

About $140 for the cheapest kit… But the technique is very similar as to what I used to do sorting amino acids, except it used plain, cheap filter paper sheets. It was almost psychedelic when ninhydrin was sprayed on the dried filter paper. Ohhh…,the colors… :wink:

I suggest you read the review. @emgoldslo had suggested other people get better quality items themselves and build their own kit, then get the things needed from the supplier that were more proprietary