Let's talk copper peptides We get asked this all the time: What's the difference between GHK and CP Serum? Here's your quick guide: GHK (first generation) Beautiful blue serum superPeptide 1% GHK Copper Peptide Serum Pure & Cimple Amazon.com: Skin Perfection Copper Peptide Serum GHK CU 1% for Face & Hair Copper Peptides for Skin, Hair, & Scalp 1% Blue Liquid for Face, Neck, Body, Scalp Multi Use Serum Booster with Frontiers Copper toxicity and deficiency: the vicious cycle at the core of protein aggregation in ALS GHK Cu Organic Serum Copper Peptide for Anti Aging & Skin Repair superPeptide 1% GHK Copper Peptide Serum Pure & Cimple