The peptides described here are supplied strictly as laboratory research materials. They are not approved, intended or authorised for human consumption or any therapeutic use. This article describes standard laboratory handling technique for qualified researchers and is not medical or dosing advice.
What "lyophilised" actually means
Research peptides ship as a lyophilised (freeze-dried) powder. Lyophilisation removes water from the frozen material under vacuum, leaving a dry, porous solid — often a small puck or a barely-visible film at the bottom of the vial. Because there's almost no water present, chemical and microbial degradation slow dramatically, which is why a sealed lyophilised vial is so stable and travels well. The trade-off is that the peptide has to be brought back into solution — reconstituted — before it can be used in any experiment.
What you need to reconstitute
Keep the working set minimal and sterile. For a standard multi-use research vial you want:
- Bacteriostatic water (BAC water). This is the standard diluent for multi-use research vials. It's sterile water containing ~0.9% benzyl alcohol, which suppresses microbial growth and lets a vial be entered more than once over a period of days or weeks. Plain sterile water or saline can be used for single-use work but offers no bacteriostatic protection.
- A sterile syringe. Used to draw the diluent and transfer it into the peptide vial.
- Alcohol wipes. To swab both vial stoppers before every needle entry.
- A clean, low-traffic work surface and clean hands or gloves. Contamination is the single most common way a reconstituted vial goes bad.
The reconstitution method
The goal is to dissolve the peptide gently, without mechanical stress. Peptides are fragile molecules and rough handling can shear or denature them.
- Swab first. Wipe the stoppers of both the BAC water and the peptide vial with an alcohol wipe and let them dry.
- Draw your diluent. Pull the chosen volume of bacteriostatic water into the sterile syringe.
- Add it slowly, down the wall. Insert the needle and let the water run slowly down the inside wall of the vial onto the powder, rather than firing it directly onto the peptide. This minimises turbulence.
- Swirl, never shake. Let it sit for a minute, then swirl gently or roll the vial between your fingers until fully dissolved. Never shake it. Shaking creates foam and mechanical stress that can degrade the peptide.
- Be patient. Most research peptides dissolve within a few minutes. If a little material clings on, more gentle swirling — not force — will finish the job.
Foaming is the visible sign of a problem: the air-liquid interface and shear forces created by shaking can unfold (denature) and aggregate peptide molecules, quietly reducing the amount of intact material in solution. Gentle swirling dissolves just as effectively without that damage.
Concentration basics
Concentration is simply total mass ÷ total volume — milligrams of peptide divided by millilitres of diluent added. Add 2 ml of BAC water to a 10 mg vial and you have a solution at 5 mg/ml. Add 1 ml to the same vial and it's 10 mg/ml. The mass of peptide never changes — only the volume of water you choose to add — so the diluent volume alone sets your working concentration. Choosing a round volume up front makes later measurement far easier. For a fully worked example, see our reconstitution guide.
Storage: lyophilised vs reconstituted
The two states have very different storage needs, and this is where most material is lost.
Lyophilised (dry) powder is the stable state. For long-term holding, keep sealed vials in the freezer; for medium-term use, the fridge is fine. Kept dry, sealed and cold, lyophilised peptides remain stable for long periods and tolerate short spells at room temperature during shipping without issue.
Reconstituted (liquid) peptide is far more delicate. Once mixed, store the vial in the fridge at 2–8 °C, protected from light, and plan to use it within roughly 4–6 weeks. Critically, never freeze a reconstituted vial — ice crystals and freeze-thaw cycles physically damage peptide in solution. The bacteriostatic character of BAC water buys you the multi-week window; it is not indefinite.
| State | Store at | Keeps for | Freeze? |
|---|---|---|---|
| Lyophilised — long term | Freezer (−20 °C) | Extended (months+) | Yes |
| Lyophilised — medium term | Fridge (2–8 °C) | Weeks to months | Not needed |
| Reconstituted (liquid) | Fridge (2–8 °C), dark | ~4–6 weeks | Never |
Our dedicated storage guide goes deeper on keeping vials stable across shipping, benchwork and long-term holding.
Common mistakes to avoid
- Shaking and foaming. The classic error. Swirl gently — if you see froth, you've been too rough.
- Freeze-thaw of liquid. Freezing a reconstituted vial, or repeatedly cooling and warming it, degrades peptide in solution. Reconstitute only what you'll use within the window.
- Contamination. Skipping the alcohol swab, reusing needles, or working on a dirty surface introduces microbes that BAC water can only partly hold back. Swab every entry.
- Leaving vials at room temperature. A reconstituted vial left on the bench between sessions loses stability fast. Return it to the fridge promptly.
- Guessing concentration. Note the diluent volume you added on the vial label so your mg/ml is never in doubt later.
The bottom line
Treat lyophilised powder as the stable, storable form — cold, dry and sealed. Reconstitute gently with bacteriostatic water, adding it down the wall and swirling rather than shaking. Then keep the liquid refrigerated at 2–8 °C, out of the light, use it within a few weeks, and never freeze it. Get those basics right and your research material stays exactly as intended from vial to bench.