How about blue green algae toxins
Need to see if palm beach county is lying to me
3 Likes
Orly?
1 Like
do we really have to calibrate before each day of use… that seems stupid expensive
2 Likes
Not sure about the SRI unit, but you’ll need clean gases too. Generators are best, use a filter either way
Get standards for phthalates and you’d make a killing showing how contaminated everyone’s stuff is with estrogenic plasticizers.
3 Likes
Rule of thumb (and what my state requires): 20 tests. Baselines shift after a few cycles, retention time may as well.
For your purposes, don’t worry about it
4 Likes
we had planned to test the same sample for a number of days to see when the numbers fell out of a normal std deviation…
just to kinda know when our shit is falling out of calibration
4 Likes
Oh, pressure changes in gas will cause issues as well. Make sure you have good regulators
1 Like
it has built in hydrogen generator and compressor
2 Likes
You’ll almost certainly need nitrogen and air for makeup gases. Not sure specifically about the SRI
2 Likes
Another cost you may run into is correction factors. If you’re having a hard time getting correct or near correct numbers from your standard, the programs comes with a calibration factor method where you can plug knowns in against the curve.
The first few things you test, you should make duplicates and send off for proper testing. Then retest those same samples against your initial calibration and plug the known values in to generate the calibration factor. Usually three duplicate samples is sufficient.
4 Likes
Zero air generator will also improve your baseline. Check the thread I hijacked to see the difference in resolution. Maybe not an issue if you’re not too concerned about low limits of detection
1 Like
we planned that… its the first thing qma said to see how close we are really getting to the test…
1 Like
Personally I would suggest you get consistent results on your machine on same sample before worrying about that.
I wouldn’t stress too much about sending off for validation. The numbers will be different, largely. I’m trying to remember the thread with a user that posted their results of samples being sent to various labs and the deviations between them.
Bear in mind the acceptable deviation is 20% in results, according to the law in my state, others I’m sure
3 Likes
I hate Sri units, only because they don’t have an auto injector
Rowan had one in Nevada and he could never get consistent results
Without an auto injector I feel like it’s hard to get consistent results because how you inject changes the results
If you dont inject THE EXACT SAME WAY everytime your results will be different
I’d start practicing the injection routine immediately
I’m not even being stupid. Just my .02 cents
3 Likes
i know its a super important factor… I know the consistancy is the only way to get consistant results…
We will be practicing with water for a while before shooting into the GC.
if you watch how hugh from SRI does it in the video and have some sorta competition to see how good you can get… im sure the perfectionist with me will get it eventually
3 Likes
How I have my stations setup currently (pardon the mess).
This is where sample prep happens. Weighed, added to a vial (add weigh boats to your supplies list), i have a bottle with my internal standard and a pump to consistently pump out 40ml. After the sample is in the vial it goes to the vortex mixer for 90 seconds. After vortexing, I remove via syringe 5ml, cap syringe with filter and empty into 2ml septa vial. Vial goes into numbered tray and data is entered into the sequence table.
This is my GC prep station, I am still manually injecting (mildly terrified I’m going to have to rip it apart again… can you get PTSD from a GC rebuild?), mostly I prep standards and get the injections ready for the machine here.
9 Likes
Just get yourself an internal standard like ibuprofen, It’ll show ya when things get wonky right away
4 Likes
Once you find out that all your canniboids have more or less (+/-2%) the same response factor, meaning that your set up works well (no leaks, nore pressure fluctuations), you can be fine with checking the machine twice a day wiyh purifued cbd isolate. This you can produce yourself from commercial isolate. Even better if you use CBN, easier to store over longer time.
2 Likes
We use Restek aswell…
2 Likes