Three storage states, three different rules. Mishandling any of them is the most common cause of “the peptide didn’t work” outcomes that aren’t actually about the compound at all.
State 1 — Lyophilized (Pre-Reconstitution)
Lyophilized peptides ship room-temperature stable. The freeze-drying process removes the water that would otherwise drive hydrolysis and bacterial growth, leaving a dry, stable cake or thin film.
Storage rules
- Room temperature (68–77°F / 20–25°C): stable for shipping and short-term storage. Most research peptides hold at full purity for 30+ days at room temp in original sealed vials.
- Refrigerated (36–46°F / 2–8°C): extends stability to 12–18 months for most compounds.
- Frozen (-4°F / -20°C): extends stability to 24+ months for most compounds. The gold standard for long-term storage.
- Deep frozen (-112°F / -80°C): 36+ months. Used in pharmaceutical research where multi-year studies are planned.
The vial seal is what preserves stability — once the seal is broken, even by a single puncture, the storage clock starts ticking on the contents.
What to avoid
- Direct sunlight or UV exposure
- Humidity above 60% RH (introduces moisture through any seal imperfection)
- Heat above 86°F / 30°C — accelerates degradation and can collapse some lyophilization cakes
- Freeze-thaw cycling on lyophilized vials (unnecessary and stresses the cake structure)
State 2 — Reconstituted (Post-BAC-Water)
Once you reconstitute with bacteriostatic water, stability drops sharply — from months/years to weeks.
Storage rules
- Refrigerated (36–46°F / 2–8°C): 30–60 days for most peptides. The bacteriostatic preservative in BAC water (0.9% benzyl alcohol) is what gets you the 60-day window. Without that preservative (using plain sterile water), you’d have ~24 hours.
- Room temperature: hours to days at most. Don’t leave reconstituted peptide on the counter except briefly during draws.
- Frozen: generally not recommended for reconstituted solutions. Freezing can denature larger peptides and shifts the BAC water’s preservative chemistry.
Visual signals of degradation
- Cloudiness in a previously clear solution (precipitate forming)
- Color change (yellow tint appearing)
- Visible particulates suspended in solution
- Off odor when the vial is opened (most peptides have minimal smell when fresh)
Any of these = discard. Don’t try to “filter and use” reconstituted peptide that’s showing degradation signs; whatever caused the visible change has likely also produced sub-visible degradation products.
State 3 — Aliquoted and Frozen (Long-Protocol Research)
For research protocols that span months and require small per-use volumes, the optimal storage strategy is to reconstitute, aliquot into single-use volumes, and freeze.
The aliquot protocol
- Reconstitute the lyophilized vial with BAC water at your standard ratio (e.g., 2 mL per 10 mg → 5 mg/mL)
- Use sterile pipette tips to transfer 100–200 µL volumes into individual sterile micro-tubes (Eppendorf-style, 0.5–1.5 mL capacity)
- Cap each tube tightly
- Freeze at -4°F (-20°C) or colder
- For each protocol day, thaw a single aliquot, draw the volume needed, discard whatever’s left in that aliquot
This avoids freeze-thaw cycling on the bulk reconstituted volume — which is the main degradation pathway for peptides in solution.
Freeze-thaw guidance
Each freeze-thaw cycle introduces a small amount of degradation, particularly for larger peptides (>20 amino acids). The published literature on peptide stability typically shows:
- 1–2 freeze-thaw cycles: minimal impact for most peptides
- 3–5 cycles: measurable degradation in larger peptides; often acceptable for smaller ones
- >5 cycles: degradation is significant enough that purity falls below the original COA values
The single-use aliquot strategy keeps every aliquot at exactly one freeze-thaw cycle, which is the cleanest way to preserve compound integrity over a long protocol.
Aliquot tube selection
Use polypropylene tubes (the standard Eppendorf material) rather than polystyrene. Some peptides — particularly hydrophobic ones — bind to polystyrene surfaces, reducing the effective concentration over time.
For very low concentrations or particularly sticky peptides, low-binding (“Lo-Bind”) tubes are commercially available and worth the small cost premium for sensitive assays.
Summary Table
| State | Temperature | Stability Window | Notes |
|---|---|---|---|
| Lyophilized, sealed | Frozen -20°C | 24+ months | Gold standard for long-term |
| Lyophilized, sealed | Refrigerated 2–8°C | 12–18 months | Practical for most labs |
| Lyophilized, sealed | Room temp 20–25°C | 30+ days | Shipping-safe; ok for short-term |
| Reconstituted with BAC | Refrigerated 2–8°C | 30–60 days | The bacteriostatic preservative is doing the work |
| Reconstituted, aliquoted | Frozen -20°C | 3–6 months | Single-use aliquots, one freeze-thaw cycle each |
What Matte Ships
Every Matte Protocol product ships lyophilized in sealed amber glass with crimp seal. The lot’s manufacture date is on the COA — most lots in stock are within 6 months of lyophilization, leaving the full storage window ahead of you.
If you want lot-specific stability data beyond what’s published on the COA, email [email protected] with the compound and lot number — we can pull the manufacturer’s stability sheet for any active lot.
Research use only. Not for human consumption, veterinary use, or as food additives. Statements have not been evaluated by the US FDA.