Copper tripeptide acetate (GHK Cu acetate) Tripeptide MedChemExpress Cu(II) Binding to the Peptide Ala His His, a Chimera of the Canonical Cu(II) Binding Motifs Xxx His and Xxx Zzz His Inorganic Chemistry 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 Buy GHKCu Copper Peptide Research Solution Lab Use