Those detector elements aren’t cheap…both the NPD “beads” and the DELCD “reactors” were a few hundred each, The NPD is a nitrogen/phosphorous detector, very sensitive (pg/g) to a lot pf pesticides that are nitrogen containing, so you could target myclobutanil as an example. The DELCD is a “dry electrolytic conductivity detector” that’s sensitive to halogen-containing compounds. Both are largely element-specific, so they’re blind to compounds that don’t contain those elements.
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I know Sri went back on their site and rewrote the pesticides information for all their gc’s. Apparently they don’t work too well. That text in the post above that I took from their site was all crossed out and old information
For the right application, SRI GCs can work well. Trace analysis of pesticides is not that application. Visit a testing lab and ask what they’re using for pesticides. Remember, the action levels are parts per billion, in relatively complex samples.
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Might be useful for remediation R&D in a pinch… no?
is a TCD or FPD is useful at all for our industry? maybe a TCD would help pick up residual solvents or the FPD pickup any sulfur based chemicals?
eternal flame (FID) for the win…
it essentially carbon counts (if it burns, we count it!). Our solvents & our target are both detectable.
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Ya I was bidding on an fid, fpd, tcd GC earlier but stopped my bid at 600 bucks lol I’m cheap
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waters or agilent HPLC with DAD, perfectly applicable systems can be had in the 10-15K range on ebay, or even from used manufactures now. so easy, no gas tanks, no trying to source helium (becoming a real issue!) no hydrogen in the lab, more accurate, and you get acid and neutral cannabinoids…
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No argument here…
I am however waiting for fedex to drop my SRI420 any moment now.
Not because it’s a brilliantly accurate machine, but because it should fit in the overhead compartment, so that when I come to your house, I can bring my own analytics
Tried a Sage (again) yesterday.
It said we had 10% CBD in our input, and none in the output, but the silly thing also said we went from negligible thc to 10% upon extraction.
Not a useful response!!!
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Oh the brief case hplc systems are coming. Microfluidics and solid state detectors. Woun’t be cheap.
I like the form factor and functionality of the orange photonics, but the price point is problematic for me right now.
long term it seems to offer greater functionality in a smaller package, and that is definitely a win for drag-around analytics.
Yeah moblie testing is not something on my radar. But I can see the why some would need it.
One can dream
maybe it’s just me…but if I’m gonna bother coming into somebody’s lab to install extraction equipment, I want to show them where the cannabinoids are going…
…and ideally set them up to do that for themselves so they can study for those 3rd party tests 
420 is here!
not quite small enough to fit in the overhead bin in it’s carry case, but it is luggable. now the fun part…
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In my case I use GC-FID, using a second hand Agilent 6850 and a HP35 column.
So far I have been using for potency testings of various type of materials (herb, extracts, tinctures), and mainly dealing with CBD rich products.
The list of cannabinoids I look at: CBD, CBDv, CBD, CBG, CBN, delta9-THC, delta9-THCv, delta8-THC and CBL.
I’m very satisfied by this system, which is pretty robust and easy to handle. In use the same device since more than 3 years, and actually do very minimal maintenance on it.
Now I’m considering to expand the analyses toward the acid cannabinoids on the one hand, and all the other lighter terpenes on the other hand. For this I’m clearly envisioning to buy a second GC, from the same brand. I’m quite interested in getting a Agilent 6890, with dual columns and FID detectors…
The idea of having a dual column would be to use two different polarity, and improve the resolution for these two next methods.
Does someone have some experience with such approach ?
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LI got mine a week ago and love it!
It is definitely more of a qualitative tool than a quantitative one, it would probably frustrate most analytical chemists.
But it looks like it will do what I need. Allow me to drag it around the country and optimize solvent to biomass ratio and extraction temperature on my Ace30 installs. I’ll post a write up when I get a chance.
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@cyclopath To be clear I’m an engineer employed by Merlin Instrument Company, however I’m on this forum for personal interests and an extraction side business. I just thought I would mention Merlin makes a handheld manual sample injector (Microshot) for GC’s. This could be a lower cost solution compared to autosamplers for repeatable injections. Most customers are using them in the field with non-chemists. You can find more info on their website (merlinic.com). Again I’m not a marketing sales person, just thought it might be a solution to your repeatability issues.
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THANK YOU @NMK
Even if you were in marketing, and looking to make the sale, this is an appropriate space for that sort of thing.
It probably won’t solve the problems with the SRI-420 (which Hugh tried to talk me out of), but it might make a world of difference for there other offerings.
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Do you derivitize? I’ve been told that the GC is inconsistent at measuring THCa without chemical modification due to inconsistencies in decarbing.
I can see @cyclopath setting up “shop” in the air port lobby waiting for his plane and testing ppls meds.
Lol
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