Not all Copper Peptides are created equal If you've tried copper peptides before and saw no change, here is why: Concentration and Stability. Most serums use a diluted solution that barely scratches Not all copper peptide serums are formulated the same Before you buy one, make sure you're actually getting pure GHK Cu at the right concentration not just a diluted blend. We spent The 1% GHK Cu Serum Phyto Exosome By Derma ProLab Blue Copper Peptide (GHK Cu) Guide: Anti Aging Science, Formulation & OEM