Copper Peptide Complexes
These are coordination complexes, not plain peptides. A short tripeptide chelates a copper(II) ion, and the complex is the material: the metal is part of what you are handling, not a contaminant. That is why the powder carries colour where an uncomplexed peptide would not.
Solvent choice matters more here than elsewhere. Chelating agents and some buffers will compete for the copper, and a complex that has lost its metal is a different compound from the one on the certificate. Storage and reconstitution notes are on each product page.
Related classes: Single-Chain Research Peptides, Bioregulator and Neuropeptides.
Certificates of analysis for every lot on this site are listed in the certificate of analysis library.