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 how much of what we believe about batch actually comes from purity threads — 52 comments in the full submission. View in context.
10k
c/coa·submitted 1 year ago by u/low_appetite_lisa

how much of what we believe about batch actually comes from purity threads

Labbranch of 8 comments

Slightly embarrassed to be asking this, but: how much of what we believe about batch actually comes from purity threads. Spent four months confusing area% and mass% in every post I made here. One explainer thread and it clicked permanently. Water content 3.8%, acetate 6.2%, purity 99%, net peptide about 90% of label…

Read the full submission and all 52 comments →

This branch

8 comments, started 1 year ago
u/hugo_bergstrom1.4k points·1 year ago

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.

replysharereportpermalink
u/ahmed_rasmussen472 points·1 year ago

batch number, date of analysis, method, individual impurities — that is the minimum set

replysharereportpermalink
u/rania_okonkwo283 points·1 year ago·edited

batch number, date of analysis, method, individual impurities — that is the minimum set

Agreed, and the practical version is: ask for the itemised table. If it exists, you get it.

replysharereportpermalink
u/low_appetite_lisaOP219 points·1 year ago

the counterion is part of the mass you paid for

replysharereportpermalink
u/alcohol_aversion1.6k points·1 year ago

The PDF creation date being later than the analysis date is usually a re-issue or a re-export. It is worth one question and it is not evidence of anything on its own.

replysharereportpermalink
u/low_appetite_lisaOP600 points·1 year ago

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

replysharereportpermalink
u/andres_restrepo134 points·1 year ago

Started keeping a folder of every certificate I have been sent. The ones that itemise impurities are a small group and they are mostly the same suppliers.

replysharereportpermalink
u/coa_collectorarchivist482 points·1 year ago

axis labels included, always

replysharereportpermalink

← 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

PeptideMeter Analytics

Independent testing plus vendor-level trend data. Community-funded, unaffiliated.

peptidemeter.com
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.
Moderators
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.