A GHK Cu face serum appears blue because the active ingredient, GHK Cu (copper peptide), is naturally a blue colored powder, meaning its inherent color transfers to the serum when mixed in; this blue hue Glutathione IM The Center Medical 1% GHK CU solution: is this applied directly on skin or diluted further? : r DIYaesthetics The Ultimate L Glutathione Supplement Guide 2022: Uses, Benefits, Side Effects & Dosing GHK Cu Copper Peptide: Dosage, Before and After Results, and How It Works Perfect B