i want to test distillate for approximate potency and for degradation/isomers. in your opinion will GC work for that? if i remember correctly i read above that it was possibly inaccurate at high potency. do you have an opinion?
At high potency just dilute your sample more in a quantitative way.
You will wind up diluting every sample anyway.
Get used to serial dilutions.
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If you do a single point @13% cannabinoids as your standard ācurveā, per the manual, then yeah at 75-99% youāre not really gonna be calibrated particularly well. So I can see where that comes from.
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Its accurate to whatever calibration curve you calibrate it to. I found it was less accurate in the low detection range 0.05%-1% even with a lot of calibration and playing around at those lower ranges.
I think the biggest thing to keep in mind is their tutorial is very basic and will not be nearly as accurate as it is capable of being.
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Iām guessing you have a āpeak reverseā event in the event table which if not un-reversed will un-reverse itself every alternate run. So Run1 is reversed, run2 is not reversed, run3 is reversed etc.
Get rid of the peak reverse event and if you have to reverse the polarity do it in the Details screen instead. Call if this is not clear.
Hugh Goldsmith
SRI
310-214-5092
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What we have been recommending lately is to make a 2 point calibration curve. Make the 13.32% calibration using the Restek standard. Then add a 2nd calibration point at 100%.
Where the amount injected in level 1 is 333ng/ul, the 2nd level would be 2500ng/ul.
You canāt buy a 100% standard, but you can inject an isolate which is either close to 100% or use a distillate for which you have a believable COA from a 3rd party lab. Select the āmultiple line segmentā method of constructing the curve and adjust the factor ( by trial and error ) so the result in PeakSimple matches the 3rd party COA . The curve should be almost linear, but not exactly linear.
Hugh Goldsmith
SRI
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PeakSimple lets you reverse the peak using the manual integration tools.
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Thatās what I thought.
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I worked some years ago with the sri 420 but it was not possible to use it with hemp plants, usually it was not able to analyse 12%cbd with 0.3% thc. it told us no thc thereā¦ changed column and septa multible times but nothing helped. not sure if the 420 was defekt or just not able to work in this percentrange.
does anyone work with the 420 at this low thc range accurate?
is the sri 310 now accurate at this low % range? 0.1-0.3%thc in combination with ~10%cbd/~16%cbg?
We designed the Model 420 to sell for a price below $5000. We had to make compromises to reach that price. It works to measure CBD or THC just fine but not small amounts of THC in CBD or vice versa. We stopped selling it ( but still support it ) because so many purchasers later wanted to do the more complicated tests and found they could not do it with the Model 420. The more expensive Model 310MM ( ( $10810 ) is what we tried to get people to buy, now and at the time, and it does exactly what you want with no compromises. When you are new to testing you may not know exactly the right questions or what you will ultimately want.
Hugh
SRI
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totally agree. @srihugh1 tried to talk me out of the 420 for days.
Iāve used the 8610C, the 310MM and the 420. the 420 is just enough tooling to be frustrating. best thing about it was I left it with a friend for a couple of weeks, and heād made himself so useful with it that the lab he was supposed to be packing tubes for purchased him an HPLC and made him their analytics department.
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