GHK Cu Copper (1%) Tripeptide Serum with Hyaluronic Acid (1.5%) Face and Scalp Serum FOUNTAIN Amazon.com: Neurogan GHK Cu (Copper Peptide) Neck & Face Serum 1,200mcg (1 oz bottle) : Beauty & Personal Care Copper Peptide (GHK Cu) Serum GHK Cu Peptide Before and After Results GHK Cu is the compound your body made at 25 and quietly stopped making. Most people find it in overpriced serums. Few understand what it actually does, or what happens when you're not