Lyophilized peptides should be stored at +4°C. Under these conditions, most peptides are stable for up to 6 months. After rehydration, aliquot the solution and freeze at -20°C to -80°C. Rehydrated, frozen peptides are typically stable for 3 months. Please avoid multiple freeze-thaw cycles.
Peptides containing Trp, Cys, and Met residues can be easily oxidized and are therefore less stable.