GHK-Cu is a tripeptide, three amino acids (glycyl-L-histidyl-L-lysine) bound to a copper ion. It was first isolated from human plasma in 1973, and it occurs naturally in your body right now, circulating in plasma, saliva and urine.
What makes it special is what it does when it reaches the skin. Copper is an essential cofactor for the enzymes that build and remodel skin tissue, and GHK-Cu acts as a delivery system, carrying copper to where the skin can use it. Research links it to increased collagen and elastin synthesis, faster barrier repair, and antioxidant activity.
The catch: our natural levels of GHK-Cu decline steeply with age, from around 200 ng/ml in our twenties to roughly 80 ng/ml by our sixties. That decline tracks closely with the visible signs of ageing skin: loss of firmness, slower healing, and thinning.
That's why we built Cuprine around it. Applying GHK-Cu topically is one of the most researched ways to give ageing skin back a signal it recognises, gently, and without stressing the barrier the way strong acids or retinoids can.