Advanced Spectroscopy for Copper Peptide Research Your copper peptide product should be this exact blue. If it isn't, you already have your answer. GHK Cu is blue because of coordination chemistry, not dye. The Cu ion at the center GHK Cu as a multifunctional copper peptide: synthesis routes, process engineering and emerging applications Systems Microbiology and Biomanufacturing Springer Nature Link Dimeric copper peptide incorporated hydrogel for promoting diabetic wound healing Nature Communications Copper tripeptide 1.xHOAc 89030 95 5 FC180071 GHK Cu 50mg Copper Peptide Research Spartan Peptides