Neurogan Health, GHK Cu Copper Peptide, Hair & Scalp Serum GHK Cu as a multifunctional copper peptide: synthesis routes, process engineering and emerging applications Systems Microbiology and Biomanufacturing Springer Nature Link 89030 95 5 GHK Cu Gly His Lys Cu Copper Tripeptide 1; Prezatide copper The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline