GHK Cu vs AHK Cu: Which Copper Peptide Is More Effective? Your skincare isn't working. But your hair is the real signal. If you're noticing thinning, shedding, or less density it's not random. And it's not just genetics. Meet GHK Cu (copper peptide): GHK Cu vs AHK Cu: Which Copper Peptide Is More Effective? GHK Cu Peptide and Hair Follicle Growth Biotech Peptides Thermodynamically stable ionic liquid microemulsions pioneer pathways for topical delivery and peptide application ScienceDirect