How Long Do Lyophilized Peptides Last? Shelf Life Explained
One of the most common questions researchers ask is how long their peptides will remain stable. The answer depends on several factors, including storage conditions, peptide chemistry, and whether the peptide has been reconstituted.
Lyophilized Peptide Shelf Life
Under optimal storage conditions, lyophilized peptides from Evolve Aminos can maintain their integrity for extended periods:
- At –20°C or below: Most lyophilized peptides remain stable for 2–3 years or longer
- At 2–8°C (refrigerated): Generally stable for several months to one year
- At room temperature: Stability decreases significantly; recommended only for short-term handling
Reconstituted Peptide Shelf Life
Once dissolved in solution, peptides become much more susceptible to degradation:
- At 2–8°C: Use within 1–2 weeks for most peptides
- At –20°C (frozen aliquots): Stable for 1–3 months depending on the peptide
- At –80°C: Extended stability of several months
Factors That Affect Peptide Stability
Temperature: Heat accelerates chemical degradation pathways including hydrolysis and oxidation. Always store peptides at the coldest practical temperature.
Moisture: Water is the primary enemy of lyophilized peptides. Even trace amounts of humidity can initiate hydrolysis of peptide bonds. Keep vials sealed and use desiccants.
Light Exposure: UV and visible light can trigger photo-oxidation of sensitive residues like tryptophan, tyrosine, and methionine. Store peptides in amber vials or opaque containers.
Oxygen: Atmospheric oxygen promotes oxidation of methionine and cysteine residues. Consider storing under inert gas (nitrogen or argon) for particularly sensitive peptides.
pH: In solution, extreme pH values accelerate degradation. Most peptides are most stable near neutral pH (6.0–7.5).
Signs of Peptide Degradation
- Change in appearance (discoloration, cloudiness)
- Reduced biological activity in assays
- New peaks appearing on HPLC analysis
- Changes in mass spectrometry profiles
Storage Recommendations from Evolve Aminos
- Store lyophilized peptides at –20°C or colder in their original sealed vials
- Minimize exposure to light by keeping vials in opaque containers
- After reconstitution, aliquot immediately and freeze unused portions
- Never refreeze a thawed aliquot — discard after use
- Record the date of reconstitution on each vial for proper tracking