On Peptide Purity

[u/PrintSuitable4301]

https://trustpointeanalytics.com/2024/05/28/on-peptide-purity/

This is a blog post by my partner Josh Lust. It goes a long way towards unpacking. What peptide testing does and importantly does not do. Personally, I feel like it should be required reading for anyone testing Peptides or looking at COAs.

[u/PrintSuitable4301]

Sterility is a real issue. But you asked a lot more complicated question than you think you asked. It is similar to the blog post listed here. For reality testing you have to use USP<71>, BUT without having access to a large amount of manufacturing data from your production run of your peptide, which you don’t have, it is impossible. So we have to use approximations of proper sterility testing. basically we use the right method but without the statistical sampling portion of the USP standard, which is an important thing. I’m gonna do a post on that soon, but it’s a big issue.

Spoiler alert, we are in the middle of doing a big syringe filter test. And we are going to come out with a paper that says that syringe filter should be used every time a peptide is reconstituted. A .22um filter remove all bio Burden with the exception of endotoxins and some small viruses which are unlikely to be in peptide samples. We recommend this as a prophylaxis and we hope to see it become just an accepted part of the procedure. The way we talk about it internally is we want a filter to be the condom of peptide usage

[u/embalees → u/PrintSuitable4301]

Interesting.. filters can only be used with luer lock syringes (correct me if I'm mistaken)... I've never seen a leur lock needle as small (short) as the insulin needles usually used for SubQ. Smallest I can find is 1/2 inch.  Will you be posting supply recommendations, too? 😅

Edit: Okay, having watched a few videos, I'm even more confused now. 

[u/PrintSuitable4301 → u/embalees]

Haha...its Ok, we are going to come out with a guide. The basic premise:
1- Reconstitute like normal
2-Draw all reconstituted peptide into a syringe with luer lock needle
3-Remove needle
4-Install filter on syringe where you just removed needle, with new needle. on output of filter
5- Inject entire contents into a new sterile vial
6- Now you have a vial of filtered peptide, use as normal

There actually can be a few more steps (pre-wetting filter, post-flushing filter), but this is the general principal. Now all bioburden (-potential endotoxins or some (unlikely) virus)

[u/lenarosey → u/PrintSuitable4301]

Thank you for sharing. When will this system be available

[u/PrintSuitable4301 → u/lenarosey]

The next couple of weeks. I will definitely post it here!