I’m also curious about this. I’ve got a bunch of Cagri that I’d hate to see go unused. I saw some 0.6% acetic acid solution vials on a few peptide sites and even on Amazon, but I’m not sure if you reconstitute with that AND bac water or just the acetic acid solution. Or how much acetic acid to add to a vial you’ve already reconstituted with BAC water. Anything specific to how we achieve this pH of 4 would be incredibly helpful, preferably by someone who has done/is currently doing this.
Unfortunately I’ve invested many hours into searching for this info and am no closer to a solid, definite answer lol.
To get the pH down would be dependent on the pH of your cagri powder, your BAC water, the pH of what you're using to drop it, and the quantity of all three. Unfortunately, it's impossible for us to give you prescriptive guidance here. Ultimately, you need the pH of the final solution to be in range.
There's two things to keep in mind, though:
1) This will not destroy any existing fibrils or oligomers that might have been created pre-lyophilization, depending on how it was formulated. Fibrils tend to clump together, so a filter might catch some that have clumped together enough to be larger than the filter size, but individual fibrils are too small to be caught by a filter.
2) The patent filing shows different buffers used to drop the pH had different impact on the ability to prevent fibrils, even at 4.0. If you don't know what buffering agent was used originally and can't reference it against the patent, or how your acid impacts it, it's even harder to tell what the impact will be.
If I was going to use cagri I would drop the pH to 4.0 and opt for smaller vials so that I am not having it sit around reconstituted for extended periods of time. If you travel with reconstituted peptides at room temp, which seems to be fine for many of them, I would probably not do so with cagri.