Positions 26–50 of 130.
Asking properly rather than in a comment on somebody else’s thread: help me understand purity, I have read the wiki twice. LC-MS gives you identity; UV purity gives you…
certificate of analysis is doing more work than we give it credit for. Change my mind, genuinely — I have no stake in being right about this. How to ask for a batch…
The title is the whole question — how much of what we believe about area percent actually comes from COA threads — but here is why I am asking. Started keeping a folder…
genuine question about area percent that I am slightly embarrassed to ask. I am not trying to be the "source?" guy. I would just like a source. The four things a…
Send the vial, get the number. Third-party purity and identity testing, results published to you regardless of what they say.
Test a vialSponsoredEst. 1998. ISO 9001 and cGMP, 1,500+ staff, 200+ patents. There is a fair chance the vial you are about to send for testing started here. Batch-specific COA as standard.
glbiochem.netSlightly 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…
Posting this as a discussion rather than a claim: the related substances thing finally clicked for me and I want to write it down. The document I was worried about…
help me understand water content, I have read the wiki twice. Searched first, found three threads that contradict each other, hence the post. Asked QSC for the…
certificate of analysis is not what most of this community thinks it is. Two minutes of reading now saves an argument later. My first certificate had a compound name, a…
why does nobody talk about area percent — that is what I am asking, and I have already read the wiki twice. Water content 3.8%, acetate 6.2%, purity 99%, net peptide…
the COA thing finally clicked for me and I want to write it down. Making the case below, and I expect to lose some of it in the comments. My first certificate had a…
18th independent test on HJ — 99.2% on a claimed 99.0%, and the trend is the interesting part. One vial, one service, one member paying, which is the only kind of…
Slightly embarrassed to be asking this, but: certificate of analysis — what am I missing here. Spent four months confusing area% and mass% in every post I made here.…
reading certificate of analysis threads from 2024 and half of it aged badly, and I am aware this is a minority view on this board. UV at 214nm sees the peptide bond and…
The title is the whole question — do related substances actually matter or is it forum lore at this point — but here is why I am asking. The PDF creation date being…
proposal — a flair for water content posts. Nothing about this affects the ranking maths, before anyone asks. Ask what the stability statement was written against —…
Vendor-level purity averages over time, built from independent results rather than vendor claims. Transparent methodology, open dataset.
Browse resultswe are measuring COA at the wrong time and calling it noise. I have gone back and forth on this for months. UV at 214nm sees the peptide bond and picks up almost…
Genuine question, and the title is the question: can we stop arguing about COA until somebody posts a number. Spent four months confusing area% and mass% in every post…
Posting this because the title is the whole finding — QSC BPC — Janoshik came back 98.7% against a claimed 98.5% — and a number without its method is a rumour. 98.7%…
purity is not what most of this community thinks it is. Two minutes of reading now saves an argument later. My first certificate had a compound name, a percentage and a…
we are measuring purity at the wrong time and calling it noise. Change my mind, genuinely — I have no stake in being right about this. How to ask for a batch record…
reading batch threads from 2024 and half of it aged badly. Making the case below, and I expect to lose some of it in the comments. My first certificate had a compound…
Posting this because the title is the whole finding — GGPeps vs GL Biochem on the same compound, same month — both cleared 99.0% — and a number without its method is a…
area percent — 13 things I got wrong before I got it right — a position I have arrived at slowly and would like tested. LC-MS gives you identity; UV purity gives you a…
related substances are the most under-discussed thing on this board. Change my mind, genuinely — I have no stake in being right about this. Water content 3.8%, acetate…
The title is the argument: unpopular opinion: most of what gets said here about COA is guesswork. Here is the rest of it. The PDF creation date being later than the…
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.
Certified reference materials for peptide identity and purity work.
sigmaaldrich.comSeveral 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.
Reference