Essential GHK Cu Serum: What It Is, How It Works, and Why It Matters f Bacteriostaticwater.com Copper Peptide Serum with 1% GHK Cu peptide, Argireline and Matrixyl 3 Dr. Brenner Labs 12 weeks in, and my skin has NEVER looked better! GHK peptides are doing their thing. Alright, I need to give you an updateit's been 12 weeks since I started using GHK COPPER GHK Mountain States Health Products Inc Multi Peptide + Copper Peptides 1% The Ordinary