What arrives in the box
Almost every peptide in this library is supplied lyophilised — freeze-dried into a powder or cake at the bottom of a small glass vial. Lyophilisation is what keeps an amino-acid chain stable during shipping and storage. It becomes usable only when you add liquid.
You need three things: the peptide vial, a suitable diluent, and a way to transfer liquid without contaminating either.
Choosing the diluent
- Bacteriostatic water contains 0.9% benzyl alcohol, which suppresses bacterial growth. It is the standard choice for a vial that will be punctured repeatedly, and it extends usable life after reconstitution.
- Sterile water for injection contains nothing else. It is appropriate only for single-use situations, because it offers no protection against growth.
Note that benzyl alcohol is not suitable for every route — it is not for intravenous administration, and it is avoided in some intranasal preparations because it irritates mucosa.
The reconstitution itself
- Let the vial reach room temperature. Condensation on a cold vial introduces contamination risk.
- Swab the stopper with an alcohol wipe and let it dry completely.
- Draw your diluent. Aim the stream at the wall of the vial, not directly at the powder — a direct jet can damage the peptide.
- Do not shake. Swirl gently, or roll the vial between your palms, until the powder dissolves completely. If it does not dissolve clear, do not use it.
- Label the vial with the compound, the concentration and the date.
The concentration calculation
This is where errors happen, so work it in steps.
Step one. Read the total mass in the vial. A typical BPC-157 vial contains 5 mg.
Step two. Decide how much diluent to add. Adding 2 ml to a 5 mg vial gives you a very different concentration than adding 5 ml. Round numbers reduce mistakes.
Step three. Compute concentration. Concentration in mg per ml equals total mass in mg divided by the diluent added in ml. So 5 mg in 5 ml is 1 mg per ml, and 5 mg in 2 ml is 2.5 mg per ml.
Step four. Work out the volume for your intended dose. Volume in ml equals desired dose in mg divided by concentration. A 250 mcg (0.25 mg) dose from a 1 mg per ml solution is 0.25 ml.
Understanding your syringe
Insulin syringes are marked in units, and one unit is not one millilitre. On a U-100 syringe, 100 units equals 1 ml, so one unit is 0.01 ml. That makes 0.25 ml equal 25 units.
Confirm this against the markings printed on your own syringe rather than assuming. Syringe scales vary, and this single conversion is implicated in more overdoses than any other calculation in this space.
Storage and usable life
- Lyophilised powder: store refrigerated, or frozen for long-term. Protect from light.
- Reconstituted solution: refrigerate. Bacteriostatic water buys you several weeks; plain sterile water gives you days.
- Never freeze a reconstituted solution — ice crystal formation damages the peptide.
- Discard anything cloudy, discoloured or containing visible particles. No exceptions.
A note on what you are not measuring
None of this tells you the compound in the vial is what the label claims, or that it is pure. Reconstitution arithmetic only protects you from your own mistakes. Protection from the supplier's mistakes comes from their certificates of analysis — and from buying from suppliers who publish them.