Randomized controlled trial of oral glutathione supplementation on body stores of glutathione Chen J., et al
Peptide Conjugation: Some forms attach the GHK-Cu to another molecule that acts as a carrier, designed to improve absorption
Kajimura, M., Fukuda, R., Bateman, R
Support your structure
Copper peptides, and specifically GHK-Cu, are one of the more interesting compounds in that marketplace because they are not new, they are not synthetic, and they have a body of research stretching back over fifty years
Gray-market peptides sold as research chemicals are not manufactured to pharmaceutical standards