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, Honest GHK CU Review: Skincare & Looksmaxing 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. GHK Cu Spray (Coppper Peptide) 100mg Limitless Biotech Ghk Cu Copper Peptide Serum Etsy Ghk Cu Intra Nasal Spray 50 mg 0.34 oz.