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, Squalane + Copper Peptide (GHK Cu) Rapid Plumping Serum Biossance GHK CU Nasal Spray KLD Peptides Revitalize your skin with the ultimate rejuvenation ally! GHK Cu Nasal Spray by Xenogenix delivers powerful copper peptide goodness to boost collagen, smooth fine lines & give you that youthful glow.