GHK CU Nasal Spray KLD Peptides GHK CU & BPC 157 Hair Foam Wellness at Century City 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. Have you heard of the peptide GHK Cu?, GHK Cu is one of the most promising peptides for improving skin health. It can promote collagen production, which is essential for skin elasticity and firmness.