peptide storage & stability calculator
find out how long your peptides last. select your peptide, storage form, and conditions to get stability timelines with degradation estimates.
for educational purposes only. stability estimates are based on general guidelines, manufacturer data, and published research where available. actual shelf life depends on manufacturer, purity, reconstitution conditions, and handling. always follow your specific product's storage instructions. consult a healthcare professional before using any peptides.
why peptide storage matters
peptides are chains of amino acids held together by peptide bonds. these bonds are susceptible to hydrolysis (breaking apart in water), oxidation, and deamidation -- processes that accelerate with heat, light, and microbial contamination. improper storage doesn't just reduce potency -- it can render your peptides completely inactive, meaning wasted money and a protocol that isn't working.
the single most important distinction is between lyophilized (freeze-dried) powder and reconstituted (mixed with water) solution. lyophilized peptides are remarkably stable because the absence of water dramatically slows all degradation pathways. the moment you add water, the clock starts ticking.
the 3 enemies of peptide stability
- heat -- every 10C increase roughly doubles the degradation rate. a vial left in a hot car for an afternoon can lose significant potency.
- light -- UV and visible light trigger photo-oxidation of aromatic amino acids (tryptophan, tyrosine, phenylalanine). some peptides like Melanotan II and DSIP are especially light-sensitive.
- contamination -- bacteria introduced through improper reconstitution technique multiply in the nutrient-rich peptide solution, producing endotoxins and breaking down the peptide.
the tool below covers all 20 peptides in our catalog. select yours to get a stability timeline, degradation curve, and storage tips specific to that peptide. if you need help with the reconstitution process itself, check our reconstitution calculator.
lyophilized vs reconstituted: the stability gap
lyophilized peptides are created through freeze-drying, which removes virtually all water from the product. without water, the hydrolysis reactions that break peptide bonds cannot occur. this is why a lyophilized vial of BPC-157 can sit in your freezer for 3 years and still be potent, while the same peptide reconstituted in water may degrade within weeks.
the type of water you use for reconstitution matters significantly. bacteriostatic water contains 0.9% benzyl alcohol as a preservative, which inhibits microbial growth and extends usable life to 2-4 weeks for most peptides. sterile water contains no preservative -- once opened, it's a perfect growth medium for bacteria. reconstituted peptides in sterile water should be used within 5-7 days maximum.
size matters: why smaller peptides last longer
as a general rule, smaller peptides are more stable than larger ones. a tiny tetrapeptide like Epithalon (4 amino acids) has fewer bonds that can break and fewer aromatic residues that can oxidize. compare this to LL-37 (37 amino acids), which has dramatically more degradation pathways and is prone to aggregation in solution. this is reflected in the shelf life estimates in the calculator above.
frequently asked questions about peptide storage
most reconstituted peptides last 14-30 days in the fridge (2-8C) when mixed with bacteriostatic water. smaller peptides like Epithalon and KPV tend to last longer (up to 30 days), while larger peptides like LL-37 may only last 7 days. using sterile water instead of bacteriostatic water reduces shelf life to about 5-7 days due to the lack of preservative.
yes, many reconstituted peptides can be frozen to extend shelf life to 1-4 months. the key is to divide the solution into single-use aliquots before freezing to avoid repeated freeze-thaw cycles, which damage peptide structure. not all peptides freeze equally well -- check the specific peptide's profile in the calculator above for recommendations.
visual signs include cloudiness or turbidity, visible particles, color changes (yellowing or darkening), and unusual odor. however, many forms of degradation are invisible -- deamidation and oxidation reduce potency without visible changes. when in doubt, follow the recommended shelf life timelines and discard expired solutions.
lyophilized BPC-157 powder can survive at room temperature for about 3 months, but refrigeration extends shelf life to 24 months and freezer storage to 36 months. once reconstituted, BPC-157 must be refrigerated and used within 21 days (with bacteriostatic water) or 7 days (with sterile water). never leave reconstituted BPC-157 at room temperature for more than a few hours.
lyophilized peptides can tolerate room temperature for days to weeks, making them safer for travel. reconstituted peptides degrade rapidly at room temperature -- most lose significant potency within hours. for travel with reconstituted peptides, use an insulated cooler bag with ice packs. see our traveling with peptides guide for a complete packing checklist.
bacteriostatic water is sterile water with 0.9% benzyl alcohol added as a preservative. the benzyl alcohol inhibits microbial growth, which is critical because reconstituted peptide solutions are nutrient-rich environments where bacteria thrive. using bacteriostatic water instead of plain sterile water roughly triples the usable shelf life of most reconstituted peptides (from ~7 days to ~21 days in the fridge).
references
- ICH Q1A(R2). "Stability Testing of New Drug Substances and Products." International Council for Harmonisation, 2003.
- USP <659>. "Packaging and Storage Requirements." United States Pharmacopeia.
- Manning MC, et al. "Stability of protein pharmaceuticals: an update." Pharm Res. 2010;27(4):544-575.
- Wang W. "Instability, stabilization, and formulation of liquid protein pharmaceuticals." Int J Pharm. 1999;185(2):129-188.
- Chi EY, et al. "Physical stability of proteins in aqueous solution: mechanism and driving forces in nonthermal aggregation." Pharm Res. 2003;20(9):1325-1336.
- Hawe A, et al. "Forced degradation of therapeutic proteins." J Pharm Sci. 2012;101(3):895-913.
- Sikiric P, et al. "Stable gastric pentadecapeptide BPC 157 in trials for inflammatory bowel disease." Curr Pharm Des. 2013;19(1):76-83.
- Pickart L, Margolina A. "Regenerative and protective actions of the GHK-Cu peptide." Int J Mol Sci. 2018;19(7):1987.
- Gentilucci L, et al. "Chemical modifications designed to improve peptide stability." Curr Pharm Des. 2010;16(28):3185-3203.
- Teichman SL, et al. "Prolonged stimulation of growth hormone and insulin-like growth factor I secretion by CJC-1295." J Clin Endocrinol Metab. 2006;91(3):799-805.
understand peptide stability science
this tool gives you storage timelines. our free module covers the chemistry behind peptide stability, reconstitution, and why storage conditions matter.