GHK Cu as a multifunctional copper peptide: synthesis routes, process engineering and emerging applications Systems Microbiology and Biomanufacturing Springer Nature Link GHK Cu Revival Clinic In Vitro and in Vivo Studies of pH Sensitive GHK Cu Incorporated Polyaspartic and Polyacrylic Acid Superabsorbent Polymer ACS Omega Frontiers Exploring the beneficial effects of GHK Cu on an experimental model of colitis and the underlying mechanisms