why does nobody talk about certificate of analysis
Trying to settle this properly because the thread from last year went in circles.
The claim: certificate of analysis matters. The counter-claim: it is measurement error. Both sides have been asserting it confidently for about 13 months without either producing anything.
What would actually settle it is 3 people measuring the same thing the same way. I have started; my numbers are below. They lean one way but not strongly enough for me to declare victory.
If you have data, post the data. If you have an opinion, flair it as an opinion.
best — the order this archive was captured in
Half-life is about 168 hours, so steady state lands around week 20–5. Practical consequence: what you feel in week 1 is not what that dose does.
no "is this good?" without saying what the compound and claimed purity are
the method line is doing real work, not just window dressing
Did they give you the chromatogram or just the summary line?
area% is not mass%, and here is exactly why it matters
Yeah, 96.8% area is not the problem, the missing impurity breakdown is the problem.
no "is this good?" without saying what the compound and claimed purity are
Dead space in the needle hub holds a small but non-trivial volume. On low-volume draws that can be several units.
chromatogram or it did not happen
This is an urgent-care question wearing a forum question's clothes. Please contact a clinician rather than waiting for replies.
This is an urgent-care question wearing a forum question's clothes.
Adding to this: batch is doing more work than the comment implies.
the method line is doing real work, not just window dressing
This is an urgent-care question wearing a forum question's clothes.
Disagree on that part. 96.8% and 96.2% on the same vial is normal.
the batch number or it did not happen
The confident tone is doing a lot of work that the evidence is not.
the counterion is part of the mass you paid for
the counterion is part of the mass you paid for
Yes, exactly this, and it is the bit that took me 23 weeks to accept.
redact your own name, not the vendor's batch details
the batch number or it did not happen
the batch number or it did not happen
Counter-anecdote: opposite result, same dose. Which mostly tells us the variance is huge.
purity and net content are two different numbers, same vial
Water content on the document? That affects your concentration math.
redact your own name, not the vendor's batch details
Metadata check caught a COA that was created in a browser four months after the analysis date. Not evidence of fraud, but worth flagging to SGN.
Metadata check caught a COA that was created in a browser four months after the analysis date.
Yes, exactly this, and it is the bit that took me 79 weeks to accept.
Water content was 3.8%, acetate was 6.2%, purity was 99%, but net peptide was only 90% of the label weight. Perfectly honest, just chemistry.
axis labels included, always
Cosigning. The batch number is load-bearing information.
- 1Half-life is about 168 hours, so steady state lands around week 20–5.…7 comments in this branch · started by u/tuva_aalto
- 2The confident tone is doing a lot of work that the evidence is not.7 comments in this branch · started by u/rohan_steiner