Whether a combination preparation is clinically appropriate for you, and the resulting cost, depends on your evaluation
GHK-Cu and Active Radicals Photodamage of tissues such as the skin involves the formation of reactive oxygen species (ROS), reactive nitrogen species (RNS), and reactive carbonyl species (RCS), which may induce damage to proteins, DNA, and lipids
DOI Sikiric P, et al
In either case, the vial should be discarded immediately
The vial lasts long enough at these low doses that stability is never a concern within the 28-day window
Every product is third-party tested by Janoshik Laboratories to verified 99%+ purity , and each batch ships with its own Certificate of Analysis (COA) so the exact material used in a study can be documented and traced