Lyophilized Peptides: Storage & Stability Fundamentals

Lyophilization — freeze-drying under vacuum — removes water from a peptide preparation while preserving its molecular structure. The resulting dry cake is dramatically more stable than a solution, which is why lyophilized formats are the standard for research materials.

Temperature is the dominant stability factor. For long-term storage, -20°C is the widely accepted baseline for lyophilized peptides. At this temperature, properly sealed material can remain stable for extended periods.

Moisture is the second threat. A lyophilized cake is hygroscopic; repeated exposure to humid air degrades the material. Allow sealed vials to equilibrate to room temperature before opening — this prevents atmospheric moisture from condensing on the cold powder.

Light exposure matters for some sequences, particularly those containing tryptophan, tyrosine, or cysteine residues. Amber storage or simple light exclusion is a sensible default.

Once reconstituted, stability windows shorten considerably. Refrigeration at 2–8°C is standard practice, and the appropriate use window varies by compound — consult published stability literature for your specific sequence.