Lyophilized research peptides are stable for extended periods when stored correctly, but reconstitution dramatically changes their stability profile. This guide covers solvent selection, technique, storage conditions, and stability expectations for the most common research compounds.
0.9% benzyl alcohol in sterile water. The benzyl alcohol inhibits bacterial growth, making BAC-W the preferred solvent when reconstituted peptide will be stored for more than 24 hours. Most common choice for multi-day research protocols.
Buy BAC-W →Plain sterile water, no preservatives. Appropriate when reconstituted peptide will be used immediately or within 24 hours. Reduces preservative interactions in certain assay contexts.
Used for peptides with poor aqueous solubility — certain hydrophobic sequences reconstitute better in dilute acetic acid (typically 1-10%). Check the product-specific literature before using.
Used for hydrophobic peptides (e.g., some steroid-derivative research compounds). Not recommended for most standard research peptides due to potential confounding effects in cell-based assays.
| State | Temperature | Typical stability | Notes |
|---|---|---|---|
| Lyophilized, unopened | -20°C | 24+ months | Stable in most freezers; protect from light |
| Lyophilized, unopened | 2-8°C (fridge) | 12+ months | Acceptable for most research peptides |
| Reconstituted in BAC-W | 2-8°C | 30 days typical, up to 60 days for stable peptides | Benzyl alcohol inhibits bacterial growth |
| Reconstituted in SWFI | 2-8°C | Up to 24 hours | No preservative; use promptly |
| Reconstituted, frozen | -20°C | Multiple months (peptide-dependent) | Avoid freeze-thaw cycles — aliquot before freezing |
| Room temperature | 20-25°C | Short-term shipping only | Not recommended for long-term storage |
For research protocols requiring specific concentrations or solvents not covered here, consult the primary literature for your specific compound and research model.
Bacteriostatic Water (BAC-W) is sterile water containing 0.9% benzyl alcohol as a preservative. The benzyl alcohol inhibits bacterial growth, allowing reconstituted peptides to be stored in solution for 30+ days refrigerated. Without the preservative (plain sterile water), reconstituted peptide solutions must be used within ~24 hours.
In bacteriostatic water, refrigerated (2-8°C): 30 days is a common target, up to 60 days for more stable peptides. In sterile water without preservative: ~24 hours. Frozen at -20°C in aliquots (avoiding freeze-thaw cycles): multiple months, peptide-dependent. Check primary literature for your specific compound's stability profile.
Shaking introduces air and mechanical shear that can denature peptide secondary structure. Vigorous shaking also creates foam, which represents air-water interface exposure that degrades some peptides. Gentle swirling allows dissolution without these issues. Some peptides take 5+ minutes to fully dissolve — patience is preferable to shaking.
Yes — reconstituted peptides can be frozen at -20°C for extended storage. Critical: aliquot first, then freeze. Repeated freeze-thaw cycles progressively degrade peptide quality. Aliquoting to single-use volumes prevents the need for repeated thaws.
GHK-Cu contains a coordinated copper(II) ion that produces the characteristic blue color in solution. This is the expected appearance of correctly-reconstituted GHK-Cu. A colorless or very pale solution may indicate degraded or incorrectly-formulated product.
For long-term storage (more than 3 months), -20°C freezer is preferred. For active-use storage, 2-8°C refrigerator is acceptable for most peptides. In both cases, protect from light and keep desiccant-adjacent if possible. Avoid temperature cycling.
Storage and stability notes are included on every COA.