In Vitro and in Vivo Studies of pH Sensitive GHK Cu Incorporated Polyaspartic and Polyacrylic Acid Superabsorbent Polymer ACS Omega PSA] Albeit rare Copper peptide "uglies" are real and scary. Case report and looking for advices : r SkincareAddiction GHK Cu is getting a lot of attention right now, and for good reason. This is not just a skin peptide. It's a copper binding tripeptide with documented effects on gene expression, collagen synthesis, GHK Cu vs AHK Cu: Which Copper Peptide Is More Effective?