GHK Cu may Prevent Oxidative Stress in Skin by Regulating Copper and Modifying Expression of Numerous Antioxidant Genes Organic Copper Peptide GHK CU Anti Aging Moisturizer Lightweight Hydrating Cream Holly What you NEED to know about GHK Cu peptide and X39 by Jen O'Sullivan of www.PatchEDU.com Here's the real difference, and it's simpler than people make it. Your body already knows GHK Cu as a multifunctional copper peptide: synthesis routes, process engineering and emerging applications Systems Microbiology and Biomanufacturing Springer Nature Link