For Research Use Only. Not for Human or Veterinary Use.
By PCL Research Team
Lyophilized (freeze-dried) peptides are sensitive to heat, moisture, light and air. How a sealed vial is received, stored, opened and logged affects whether the material is still what your records say it is when it reaches the bench. This guide collects general laboratory practice published by established peptide suppliers, a university chemical hygiene plan and U.S. safety regulators. Every specific temperature cites its source.
Start with the product documentation. Storage conditions differ by compound and sequence. Where the product page or its documentation gives a condition, that condition takes priority over the general practice described here. This guide does not replace your institution’s procedures, your chemical hygiene plan, or your principal investigator’s instructions.
This guide covers sealed lyophilized material only.
At a glance: general lab practice from published supplier guidance
| Situation | General practice (published) | Source |
|---|---|---|
| Sealed lyophilized vial, longer-term | −20 °C, away from bright light | GenScript [S1] |
| Sealed lyophilized vial, longer-term | Below −15 °C in a tightly closed container | Bachem [S2] |
| Sealed lyophilized vial, long-term where available | Lower temperatures preferred, e.g. −50 °C or lower | Bachem [S2] |
| Lyophilized, short-term use | Refrigerator at 4 °C | Bachem [S2] |
| Before opening a cold vial | Let it reach room temperature (in a desiccator) before removing the cap | GenScript [S1]; Bachem [S2] |
These are general figures, not specifications for any particular PCL Research product. Always confirm against the product documentation.
1. Receiving and inspection
When a shipment arrives, check it before anything goes into storage:
- Outer packaging: note any crushed, wet or opened packaging before you unpack.
- Each vial: check the integrity of every container [S5]. The seal and cap should be intact with no cracks, and the contents should look like a dry powder or cake, not liquid or visibly wet material.
- Label against paperwork: the product name, size and lot or batch number on the vial match your order and packing slip. Leave the original label in place. Labels on incoming containers must not be removed or defaced [S5].
- Log on arrival: record the date received, who received it, the lot number and where it was stored (see Section 5).
- Store promptly: move vials to the storage condition stated in the product documentation without delay.
If anything doesn’t match, set the vial aside, label it “on hold” and contact PCL Research through the contact page before using it.
2. Temperature storage for sealed lyophilized vials
Published supplier guidance agrees on the direction: colder is better for longer storage.
- GenScript advises −20 °C, away from bright light [S1].
- Bachem advises keeping the lyophilizate in a tightly closed container below −15 °C for longer storage, and prefers lower temperatures (e.g. −50 °C or lower) for long-term storage [S2].
- For short-term use, Bachem notes that a refrigerator at 4 °C may be used [S2].
- After a vial has been opened, GenScript advises storing the remaining peptide in a freezer, preferably below −20 °C, under dry conditions [S1].
Stability is sequence dependent. GenScript notes that peptides containing cysteine (Cys), methionine (Met) or tryptophan (Trp) are prone to oxidation [S1], and Bachem notes that peptides containing Asn, Gln, Met, Cys and/or Trp have limited shelf lives [S2]. Use the product documentation as the authority for each compound.
3. Light, moisture, desiccation and opening cold vials
- Light: store vials away from bright light [S1]. Opaque secondary boxes in the freezer help.
- Moisture: peptides tend to be hygroscopic, and absorbed water reduces the overall peptide content and may decrease stability [S2]. GenScript recommends desiccator storage in a tightly capped vial for peptides containing Asp, Glu, Lys, Arg or His, which are prone to absorbing moisture from the air [S1].
- Equilibrate before opening: take the vial out of cold storage and let it reach room temperature before removing the cap [S1]. Bachem recommends doing this in a desiccator [S2]. This keeps moisture from the air off the cold powder.
- Work quickly, then reseal: weigh out what you need quickly, reseal the container tightly, and return the remainder to cold, dry storage [S1][S2].
- Air: for oxidation-prone sequences (Cys, Met, Trp), limit exposure to air and keep vials tightly capped [S1].
4. Aliquoting to avoid repeated freezing and thawing
Peptides that are repeatedly frozen and thawed are susceptible to degradation [S1], and GenScript advises against repeatedly opening the stock vial [S1].
- Plan aliquots up front: work out how much material each experiment needs, and divide the lyophilized material into separate vials accordingly before first use [S1].
- Fewer openings, less air: aliquoting also reduces the amount of air exposure to the peptide [S1].
- Track it: give every aliquot its own label and a line in the inventory log (Section 5).
5. Labeling, inventory and lot tracking
Good records make it possible to trace an observation back to a specific lot and handling history. University chemical hygiene plans set the baseline. For example, Eastern Kentucky University’s plan says all containers must be labeled, and that the label should include the product identifier, the date prepared, received or opened, and the name of the user [S5]. It also says damaged or semi-attached labels should be replaced [S5].
Label every vial and aliquot with:
- compound name (product identifier)
- lot or batch number (copied exactly from the original vial)
- date received, date opened, or date the aliquot was made
- user’s name or initials
- storage condition and location (e.g. freezer and rack)
- any hazard information your institution’s labeling rules require
Keep an inventory log or lab-notebook entry for each lot:
- supplier, product name, size and lot number
- date received and condition on arrival
- storage location and condition
- date first opened
- aliquots made (ID, amount, date) and when each was used or discarded
- any deviation, such as a freezer excursion, a damaged seal or an unexpected appearance
Keep the product documentation for each lot with your records (see product documentation).
6. PPE, lab safety, SDS and disposal
- Follow your chemical hygiene plan. In the US, OSHA’s Laboratory standard requires employers whose labs use hazardous chemicals to keep a written Chemical Hygiene Plan. The plan covers control measures, personal protective equipment, work practices and procedures for safe removal of contaminated waste [S3].
- PPE: wear the PPE your institution specifies for the materials in use. This commonly includes a lab coat, gloves and eye protection. Bachem recommends a dust respirator when handling larger amounts of peptide lyophilizates [S2].
- Safety Data Sheets: OSHA requires labs to keep on file the safety data sheets received with incoming shipments of hazardous chemicals, and to make them readily available to employees [S3]. Under the Hazard Communication Standard, SDSs follow a 16-section format [S4]. Review the SDS for each hazardous chemical you use.
- Spills and exposure: follow your lab’s posted emergency procedures and the SDS.
- Disposal: dispose of unused material, contaminated consumables and empty vials according to your institution’s EHS office rules and local regulations. Don’t improvise disposal routes.
Printable checklist: sealed lyophilized research peptides
Receiving
- ☠Packaging intact; any damage noted
- ☠Every container checked for integrity [S5]; seal and cap intact; contents look dry
- ☠Product name, size and lot number match the order and packing slip; original label left in place [S5]
- ☠Received date, receiver and lot logged
- ☠Stored promptly per the product documentation
Storage
- ☠Storage condition taken from the product documentation (general practice: −20 °C [S1], or below −15 °C [S2], for longer-term storage)
- ☠Away from bright light; desiccated where appropriate [S1]
Opening
- ☠Vial brought to room temperature (in a desiccator) before opening [S1][S2]
- ☠Weighed quickly; vial resealed tightly; remainder returned to cold, dry storage [S1][S2]
Aliquots and records
- ☠Single-use aliquots planned and prepared; stock vial not repeatedly reopened [S1]
- ☠Every vial and aliquot labeled (product identifier, lot, date received/opened/made, user, location) [S5]
- ☠Inventory log updated, including deviations
Safety
- ☠PPE per the institution’s requirements
- ☠SDSs for hazardous chemicals on file and reviewed [S3]
- ☠Waste disposed of per institutional EHS rules [S3]
Frequently asked questions
How should sealed lyophilized research peptides be stored?
Follow the storage condition in the product documentation first. As general lab practice, GenScript recommends −20 °C, away from bright light [S1]. Bachem recommends below −15 °C in a tightly closed container for longer storage, and prefers −50 °C or lower for long-term storage [S2].
Do lyophilized peptides need to be refrigerated?
For short-term use, Bachem notes that lyophilized peptides may be kept in a refrigerator at 4 °C [S2]. For longer storage, both suppliers recommend freezer temperatures: −20 °C [S1] or below −15 °C [S2]. Neither recommends room temperature for longer storage.
Why should a vial reach room temperature before it is opened?
Peptides tend to be hygroscopic, and absorbed moisture reduces the overall peptide content and may decrease stability [S2]. Let the sealed vial warm to room temperature, ideally in a desiccator, before removing the cap [S1][S2].
How can I avoid repeated freezing and thawing?
Plan how much material each experiment needs and divide the lyophilized material into separate vials before first use, so the stock vial isn’t repeatedly opened [S1].
What should I record for each lot?
Record the supplier, product name, size, lot number, date received and condition, storage location, date opened, every aliquot made and used, and any deviation. Label each vial and aliquot with the product identifier, lot, relevant date and user [S5].
Where do I find safety and disposal information?
Use the Safety Data Sheets your lab keeps on file for hazardous chemicals, your institution’s chemical hygiene plan, and your EHS office’s disposal rules [S3][S4].
Are PCL Research products intended for human or veterinary use?
No. All PCL Research products are designated For Research Use Only and are intended solely for laboratory and scientific research applications. See the Research Use Disclaimer and Terms of Service.
Sources
- [S1] GenScript, “Peptide Storage and Handling Guidelines.” https://www.genscript.com/peptide_storage_and_handling.html
- [S2] Bachem, “Handling and Storage Guidelines for Peptides.” https://www.bachem.com/knowledge-center/handling-and-storage-guidelines-for-peptides/
- [S3] U.S. OSHA, 29 CFR 1910.1450, “Occupational exposure to hazardous chemicals in laboratories.” https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1450
- [S4] U.S. OSHA, “Hazard Communication.” https://www.osha.gov/hazcom
- [S5] Eastern Kentucky University (EHS), “Chemical Hygiene Plan” (PDF). https://files.eku.edu/public/AdministrationEngagement/FacilitiesManagement/EHS/Chemical-Hygiene-Plan.pdf
Browse the PCL Research catalog and see each product page for its documentation. More answers are in our FAQ.
For Research Use Only. Not for Human or Veterinary Use.