The GHK Cu pen works. But needles at home were never the answer. We took the same clinically backed copper peptide complex and put it into a serum you can use in 30 seconds, GHK Cu as a multifunctional copper peptide: synthesis routes, process engineering and emerging applications Systems Microbiology and Biomanufacturing Springer Nature Link GHK Cu vs AHK Cu: Which Copper Peptide Is More Effective? Chemical structures of GHK and its copper and palmitoylated (Pal) Download Scientific Diagram