Peptide Critic Community

I’ve been looking at this web site for a few months now, and really like it.
It seems that the top referenced sellers like EX, Mile High, etc all seem to get good, >99% purity.

But, some of even the highest rated do not report Endotoxin results. For your own information, <5EU/mg is NOT a numbered result. If you look at a few sellers, they actually report the result like 0.078EU/mg for example.
Reporting <5EU/mg means it could be 4.9.

A report listing "< 5 EU/mg" usually means the laboratory set their testing equipment to a highly lenient detection threshold. Rather than looking for absolute trace purity, they are only confirming that the sample is free of massive, systemic bacterial contamination.

A < 5 EU/mg specification is the absolute baseline bare-minimum for chemical legitimacy. Premium vendors looking to eliminate variables will typically test past this threshold to prove their batches achieve the much stricter limits—like < 0.05 EU/mL or even better an actual number if not <0.05.

So look at the COA’s presented from your favorite sellers. If the actual Endo isn’t reported, my recommendation is to move on to a cleaner set of samples from a different seller.

I've been using Krause Analytical for a while. No problems.

I had been doing the order grey market by the box, getting them tested, and usually being disappointed. Some were good, like Yuansense Tech. Some were mediocre, like Vertex Bio, and some were ugly, like Nanjing Bio.
I decided it just wasn't worth the effort to save a few bucks, and ordered from Northline Labs for a while, until I found Southern Aminos. For the price and peace of mind, that one is a standout.
Let's take 1 20mg Tirz for example. From grey China, about $125 to $150 a box if you include shipping. So about $15 per vial. Then you include testing, and let's call that $250 if you have the Endo done with the Purity and ID. So now we're at $400 for 9 vials. That's $44 per vial.
I just bought three vials 20mg Tirz from SA for $165, or $55 per vial. Is it really worth all the effort for $11? IMHO not.
I also have been looking at Quest Molecular Peptides. https://qmpeptides.com/ Good prices, excellent testing QA, and quick response and shipping. That's one to look at also..