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 89030 95 5 GHK Cu Gly His Lys Cu Copper Tripeptide 1; Prezatide copper What is GHK Cu Collagen and Elastin Support Neurogan Health Triad City Beat GHK: A Minimalist Tripeptide at the Crossroads of Regenerative Signaling and Molecular Coordination