GHK Cu (10 mg, 50 mg, 100 mg) COA verified peptide Nootropix Copper peptides are everywhere in serums, scalp treatments, and influencer recommendations. But does the science actually support the hype? The answer: yes, with nuance. GHK Cu is a naturally occurring tripeptide found GHK Cu Copper Peptide Hair & Scalp Serum Amazon.com : Mayraki Intense Hair Treatment with Copper Peptide GHK Cu, DHT Blocker for Thicker, Stronger Hair Growth 45 ml 1.52 fl. oz : Beauty & Personal Care