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 Skin Perfection GHK Cu Copper Peptide Serum Booster, 1 Percent Blue Liquid For Face, Neck, Body, Hair, And Scalp, 0.5 oz Walmart.com Concentrated Copper Peptide Serum Booster for Skin and Hair Natural Copper Peptide Serum Booster