BAC water vs sterile water

krsct

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Here is a link to an interview featuring Peter Janoshik from the testing company that shares his name. He discusses how he entered this field and shares several observations. Notably, he confidently claims that bacteriostatic water isn't required when mixing peptides. He mentions that sterile water is an option. He acknowledges this view is controversial.

View: https://youtu.be/shgk3-u51Ys?si=4jl4kcH7ynyHYl6L
 
Not controversial?

Bacteriostatic water isn't what you use to "mix" — its purpose is stopping microbiological growth inside your vial.

Using sterile water for peptides comes up constantly. Plenty of people rely on it, particularly in places where bac water is hard to obtain.

Another thing to weigh when reconstituting is pH, since some peptides are a bit more sensitive than others. That can mean you need AA, and I've come across people mentioning a few drops of DMSO for certain substances, though that's far beyond anything I've dealt with.
 
krsct said:

Here is a link to an interview featuring Peter Janoshik from the testing company that shares his name. He discusses how he entered this field and shares several observations. Notably, he confidently claims that bacteriostatic water isn't required when mixing peptides. He mentions that sterile water is an option. He acknowledges this view is controversial.

View: https://youtu.be/shgk3-u51Ys?si=4jl4kcH7ynyHYl6L

If you're reconstituting a peptide and plan to finish the entire vial immediately, sterile water may work fine, provided it's the right peptide for that approach. The trouble with sterile water is that contamination happens easily — sticking a needle into it or leaving it open to the air is often enough.

Bacteriostatic water works differently: the benzyl alcohol in it keeps bacteria from multiplying, which means a peptide mixed with bac water is less prone to bacterial growth while it sits in storage.

That said, benzyl alcohol can fade over time, so it isn't a permanent solution for long storage windows. And bac waters vary in quality — but that's a separate topic, like the bacteria colonizing your fridge 😀
 
yrrdead said:

Not controversial?

Bacteriostatic water isn't what you use to "mix" — its purpose is stopping microbiological growth inside your vial.

Using sterile water for peptides comes up constantly. Plenty of people rely on it, particularly in places where bac water is hard to obtain.

Another thing to weigh when reconstituting is pH, since some peptides are a bit more sensitive than others. That can mean you need AA, and I've come across people mentioning a few drops of DMSO for certain substances, though that's far beyond anything I've dealt with.
The disagreement exists since most folks keep their reconstituted peptides around for 4 weeks or longer, which is exactly when BAC water becomes necessary. Saline, on the other hand, is meant for 1 immediate use. A few experts felt Peter should have stuck closer to his own area of expertise...
 
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