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 100mg Research Compound Australia Molecular crystal structure of the tripeptide GHK Cu. In solution, Download Scientific Diagram 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