GHK Cu Copper Peptide: The Ultimate Peptide For Longevity GHK Cu vs NAD+: Which Longevity Peptide Should You Take or Stack? The GHK Cu pen works. But needles at home were never the answer. We took the same clinically backed copper peptide complex and put it into a serum you can use in 30 seconds, DAILY SPOTLIGHT GHK Cu 200mg from Peptide Partners. GHK Cu is the copper tripeptide biohackers reach for when skin, scalp, and wound repair all need a single upstream signal. Endogenous in healthy human