Preprint on grey peptide quality

Enyola

Enyola

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Evaluation of Research Grade Peptides Marketed Directly to Consumers Reveals Extensive Variability in Purity and Measured Abundance

I am very aware of the forum's easter egg regarding the data source of this study. I have read the threads and seen the videos. I thought about writing to the authors, because bad original data screws the study as a whole, of course. But arguing on the base of anecdotal evidence or youtube videos doesn't cut it. ChatGPT tells me there is no scientific evidence.

What would you do?

How can it be that there is no external quality control on this lab?

Do they get away with it just because their customers don't have interest in putting legal attention to themselves?
 
The data they are using is not that bad, there are some issues, overall there is a lot of consistency there. I think the conclusions of the study are probably fair.

You have to keep in mind that our experience with Chinese vendors does not represent the general publics. This forum's participants are small slice if the general peptide market. There are probably a lot more people buying from scamers on Tik-Tok than from 'reputable' vendors.

We have access to high quality Chinese peptides. Most of the people buying these peptides will never do the work we have done to insure that. So yes, for your average person, the peptide market is a dangerous place with a lot of poor quality products and total fakes.
 
Without even reading the content, I have zero doubt the variable quality in the flood of "cheap" reconned product exists. I believe the variation to be great.
 
Enyola said:


Evaluation of Research Grade Peptides Marketed Directly to Consumers Reveals Extensive Variability in Purity and Measured Abundance

I am very aware of the forum's easter egg regarding the data source of this study. I have read the threads and seen the videos. I thought about writing to the authors, because bad original data screws the study as a whole, of course. But arguing on the base of anecdotal evidence or youtube videos doesn't cut it. ChatGPT tells me there is no scientific evidence.

What would you do?

How can it be that there is no external quality control on this lab?

Do they get away with it just because their customers don't have interest in putting legal attention to themselves?

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Enyola - thanks for posting this study. It makes for interesting reading and raises my awareness of the possible risks in the use of gray-market peptides, risks I was already reasonably aware of before taking the plunge, but the study provides some measurements of the scope of those risks. I don't understand though, what you're saying about the study. Can you clarify please? I'm not asking as a criticism but as a confession of my ignorance as a newcomer to this field.
 
@reta-stacker:

You can read this thread (not just the beginning!) and watch this video - and you will know what I mean.

You have to keep in mind that our experience with Chinese vendors does not represent the general publics.

Click to expand...
Click to expand...
Actually I haven't been very aware of this. I didn't have any contact with the topic outside of here and stg.
 
The variations discussed in the videos are common.

A modern HPLC system, when optimally calibrated, has a minimum uncertainty of 0.3%, and more frequently 0.5%-1%. Therefore, debating values between 99.4 and 99.5 is meaningless.

Variations between laboratories, especially if they do not use the same machines or the same protocols (eluent, flow rate, temperature, etc.), are typically 2% or even 5%.

In the video of the tour of the Janoshik lab, we can see that they have Shimadzu equipment, and the instrument that PM says is reserved for aGLP-1 peptides is an i-Series (2050 something).

The specifications are available on the manufacturer’s website. However, they are not expansive about the uncertainties; you have to dig a little deeper.

If you’re curious, I recommend checking out the Agilent website, another manufacturer. They’ve conducted detailed analyses of Tirz, Sema, Lira, and others. You can see that they’re capable of identifying excipients and residual salts. There are also tests using different eluents and other variations in the analytical protocol that show how results can vary depending on the protocol, and how degradation products may be detected in one case but not in another.
 
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