Molecular crystal structure of the tripeptide GHK Cu. In solution, Download Scientific Diagram Copper peptide (GHK Cu) SIELC Technologies GHK Cu as a multifunctional copper peptide: synthesis routes, process engineering and emerging applications Systems Microbiology and Biomanufacturing Springer Nature Link N2 (N Glycyl L histidyl) L lysinato(2 )]copper 89030 95 5 wiki 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