Ingredient or product comparison
Lyophilized Shelf Life vs Reconstituted Stability
Unreconstituted GHK-Cu in lyophilized powder form remains stable for 24–36 months when stored at −20°C in airtight, desiccated packaging. The copper (II) ion remains coordinated with the tripeptide in solid phase, and degradation pathways (oxidation, hydrolysi
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- Unreconstituted GHK-Cu in lyophilized powder form remains stable for 24–36 months when stored at −20°C in airtight, desiccated packaging. The copper (II) ion remains coordinated with the tripeptide in solid phase, and degradation pathways (oxidation, hydrolysis) are arrested without aqueous solvent. This is why peptide suppliers ship lyophilized. It's the only form that tolerates shipping temperature excursions and long-term storage without measurable potency loss.
- Once reconstituted with bacteriostatic water, GHK-Cu stability drops to 28 days under refrigeration at 2–8°C. This isn't a conservative estimate. It's based on HPLC (high-performance liquid chromatography) analysis showing that copper-peptide complex integrity begins declining after four weeks in solution. The degradation isn't linear: you don't lose 3% per week for 10 weeks until it's gone. Instead, copper dissociation accelerates after 28 days as the peptide backbone undergoes hydrolytic cleavage, particularly at the glycyl-histidyl bond.
- This creates the core constraint when you choose GHK-Cu vial size: you must consume the entire reconstituted volume within 28 days, or you must accept that later doses are chemically inferior to earlier doses. A 200mg vial reconstituted in full for a 2mg daily protocol would theoretically last 100 days. But only the first 28 days' worth would meet the stability specification. Days 29–100 would deliver progressively less intact GHK-Cu and progressively more free copper ions and cleaved peptide fragments, neither of which replicate the biological activity of the intact complex.
- Solution: match vial size to 28-day consumption limits. If your protocol uses 56mg per 28-day cycle, a 50mg vial requires slight dose adjustment (1.78mg daily instead of 2mg) or opening a second vial on day 26. A 100mg vial commits you to either running two simultaneous 28-day cycles with separate reconstitution dates or freezing half the lyophilized powder before reconstitution. Which is feasible but requires splitting the vial's contents under sterile conditions before adding solvent.