GLPHubglpresearchhub.com
Read-only archive. GLP Research Hub is a static community record — nothing here is for sale, no account is needed, and no vote you cast is counted. Why?
Single comment threadYou are looking at one branch of help me understand COA, I have read the wiki twice — 30 comments in the full submission. View in context.
1.9k
c/coa·submitted 2 months ago by u/andres_restrepo

help me understand COA, I have read the wiki twice

Suspiciousbranch of 6 comments

Slightly embarrassed to be asking this, but: help me understand COA, I have read the wiki twice. My first certificate had a compound name, a percentage and a logo. I thought that was normal. It is not, and now I know what to ask for. How to ask for a batch record without it turning into a negotiation. One email,…

Read the full submission and all 30 comments →

This branch

6 comments, started 2 months ago
u/dario_boateng54 points·2 months ago

What does the method line actually say? Not the technique — the column and the gradient.

replysharereportpermalink
u/soren_zamora26 points·2 months ago

Yes — and the reason to ask for the whole page is that the interesting parts are the ones people crop out to fit a screenshot.

replysharereportpermalink
u/andres_restrepoOP20 points·2 months ago

the related substances line is where the story is

replysharereportpermalink
u/andres_restrepoOP14 points·2 months ago

Correction: that is net peptide content, not purity. Different number, different meaning, and the document says so if you read the row label.

replysharereportpermalink
u/tidy_vialdrawer_pls15 points·2 months ago

Is water content on the document? It changes your concentration arithmetic.

replysharereportpermalink
load more comments (1) →

← back to the whole thread

About c/coa

How to read a certificate of analysis and what it does and does not tell you. Area% versus mass%, identity versus quantity, water content, related substances, acetate counterions, and the difference between a vendor-supplied COA and an independent test on the vial you actually received.

71kmembers
130submissions
Aug 2023created
submissions / month, last year
Sponsored

Sigma-Aldrich Standards

Certified reference materials for peptide identity and purity work.

sigmaaldrich.com
More in c/coa
c/coa rules
  1. Post the full document. Cropped COAs that hide the batch number or date get removed.
  2. Redact your own name and order id, not the vendor's batch details.
  3. No "is this good?" without saying what the compound and claimed purity are.
  4. Independent community. Nobody here sells anything, and anyone who tries is banned.
  5. Not medical advice. Describe what you did; never prescribe to a stranger.
  6. Claims need evidence. Batch numbers, dated screenshots, independent test reports, or a citation.
  7. No referral links, discount codes or affiliate URLs. Permanent ban, no appeal.
  8. No contact handles, wallet addresses or tracking numbers — they identify people.
  9. Be recognisably decent. Disagree hard, insult nobody.
Full rules and how they are enforced →
Moderators
u/coa_janitoru/purity_pedantu/coa_collectoru/certified_referenceu/first_hundred
Volunteers. Unpaid, unaffiliated, and reachable through modmail only.
Before you read on

Several compounds discussed on GLP Research Hub are sold for research use only and are not approved for human use anywhere. Nothing here is medical advice and none of it is written by your clinician. If a post reads like an instruction, treat it as a description of what one stranger did.

Full disclaimer →