GHK-Cu
Copper tripeptide-1. Studied in extracellular-matrix and fibroblast research.
GHK-Cu is a tripeptide — glycine, histidine, lysine — complexed with a copper(II) ion. First isolated from human plasma in the 1970s, it declines with age and has since accumulated one of the broadest research literatures of any short peptide: skin biology, wound models, hair-follicle studies, and large-scale gene-expression profiling.
The copper coordination is the interesting part chemically. GHK binds copper with high affinity, and much of its studied activity — collagen synthesis signaling, antioxidant enzyme support, matrix remodeling — appears tied to controlled copper delivery into cells. Gene-array work has reported GHK influencing expression across a strikingly large fraction of the genome.
Its small size (403 g/mol) makes it the lightest peptide in the catalog and gives it distinctive handling properties; the blue-violet color of the copper complex is also the most recognizable vial in the case. Supplied HPLC-verified for laboratory research.