Lyophilized Peptides: Best Practices for Storage, Handling, and Stability (RUO)
Proper handling of lyophilized (freeze-dried) peptides is essential for preserving their stability, purity, and performance in controlled laboratory environments. Although lyophilization significantly increases shelf life, environmental factors like moisture, temperature fluctuations, and repeated freeze–thaw cycles can still degrade peptide integrity.
This guide provides clear, RUO-appropriate best practices for receiving, storing, reconstituting, aliquoting, and disposing of lyophilized peptides in a research setting.
On Arrival: Inspection, Logging, and Documentation
When receiving a new peptide batch:
-
Verify packaging integrity — check that vials, seals, and caps are intact.
-
Record the batch details in your inventory system, including lot number, concentration, date received, and storage location.
-
Store documentation — file COA and SDS for reference and cross-verification.
-
Minimize the peptide’s exposure to heat, light, or humidity during the intake process.
Storage Conditions for Lyophilized Peptides (Dry State)
Lyophilized peptides are generally stable, but proper storage extends their shelf life and preserves structure.
1. Temperature
-
Follow the storage temperature listed on the COA or label.
-
Many lyophilized peptides remain stable at –20°C or lower.
-
Short-term storage (2–8°C) may be acceptable depending on sequence and complexity.
2. Moisture Protection
-
Lyophilized peptides are hygroscopic — they readily absorb moisture.
-
Keep vials tightly capped until use.
-
Store in a low-humidity, desiccant-protected environment.
3. Light Exposure
-
Some sequences are light-sensitive.
-
Store in a dark container, or a light-protected box.
Reconstitution: Preparing Peptides for Experimental Use
Reconstitution introduces the highest risk of peptide degradation. Careful technique helps maintain stability.
-
Plan your workflow so the peptide is reconstituted only when required.
-
Use appropriate diluents (Reconstitution Solution, also known as Bacteriostatic Water or Bac Water)
-
Add solvent gradually down the vial wall to avoid foaming or shearing.
-
Gently swirl — do not vortex, as mechanical agitation may denature some sequences.
Aliquoting Strategy: Preventing Repeated Freeze–Thaw Cycles
Repeated freeze–thaw cycles are one of the most common causes of peptide degradation.
To reduce this risk:
-
Reconstitute to a concentration convenient for your specific assays.
-
Label each vial clearly with:
-
Peptide name
-
Concentration
-
Volume
-
Lot number
-
Date prepared
-
Stability Considerations After Reconstitution
pH and Buffer Compatibility
Use buffers that match the peptide’s chemistry and recommended pH range. Extreme pH can rapidly degrade many sequences.
Short-Term vs. Long-Term Storage
-
Follow COA or institutional guidance for ideal storage temperatures (often –20°C or –80°C).
-
Avoid temperature cycling.
-
Use aliquots quickly once thawed.
Time-in-Use
Many peptides have limited stability once in solution. Follow your lab’s validated window and discard solutions outside of SOP limits.
Disposal and Safety
-
Follow your institution’s chemical hygiene plan and local regulations for peptide disposal.
-
Never discard peptides via standard waste streams unless approved by your facility’s safety office.
RUO Notice
This information is intended exclusively for laboratory research use only (RUO).
Not for human consumption, clinical use, diagnostic procedures, or veterinary applications.
