In house vs. 3rd party testing results

Testing and Analytics
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CBD isolates usually contain some 0.1-0.8% CBDv, plus another one in similar or lower poportions (CBD dimer ? CBD quinone ? I’m still not sure), even after several crystallization. So each 99+ isolate has in fact it own identity. You can discern them with a finely tuned GC. :nerd_face:

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42

@PaulyFerg
I would consider over 2% difference from a commercial standard on your quality checks a no-no.

  1. Did you generate the calibration curve yourself? What is R2? Should be 0.999-ish.

  2. If yes, where did you buy standards? There are issues with standards:
    a. if you dont keep them in a freezer and dont try to use them rather soon after opening; building a calibration curve at 10% off can happen easily - then all your analyses will be 10% off.
    b. If you built your calibration curve with a standard from one company, did you validate against the same standard from a different company?
    Some companies standards are downright awful - Restek - an established standards company sends out d9-THC prepared gravimetrically, no CoA; says purity is 98% - guess what the standard really is. We purchase standards from Absolute Standards - cant say enough good words about their work.

  3. This way you eliminate the standards issue.

  4. I assume you use auto-pipettes when you say you do their calibration - they are not very good with organic solvents. Switch to a glass pipette.

  5. Do you know how to properly use HPLC injection microsyringe? While trivial, many people don`t.

  6. What injection volume you use? Why not over the injector volume (usually 20 uL)? This way you assure consistency.

  7. What analytical balance are you using? If cheap balance and not with at least 1mg precision, then this can be an issue too.

  8. During your HPLC runs, do you control temperature? It has a significant impact on peak RT, as well as height.

  9. Is this lab you are referring to doing anything above and you are actually right and they are wrong? Just because it is a certified lab, doesn`t mean the person setting up the method was doing things correctly.

  10. How do you prep sample?