GHK Cu Dosage Chart and Calculator: How to Use This Peptide Safely Peptides Unleashed I've been getting a lot of questions about GHK Cu, so here's a quick breakdown. GHK Cu is a copper peptide that naturally occurs in the body and plays a role in skin repair 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 Liposomal Copper GHK (Quicksilver Scientific)