Someone said this : “The claim is that the ions in PBS can neutralize the positive charge of the copper ions, which reduce the overall likelihood of oxidation that would normally destabilize the copper in GHK-Cu when reconstituted with BAC water. The claim also mentions that PBS also maintains a stable pH, which is important for keeping copper in its soluble form, as in BAC water or regular saline the changes in pH can lead to precipitation or oxidation of copper ions ("5 to 7 for BAC and saline, vs 7.2 to 7.4 for PBS"). So if you use BAC water, you're only getting GHK and not the Cu, and a higher likelihood of injection site pain/ damage.”