Peptide Dilution Calculator
Calculate concentration, draw volume, and syringe scale for laboratory peptide dilution.
How much active substance does it contain in total?
How much active substance should be drawn per dose?
This determines the concentration of the solution. 1 ml and 2 ml are the most common — 2 ml is a good starting point.
Determines up to which volume the result can be drawn in a single pull.
Basics: Lyophilization and Reconstitution
Research peptides are supplied lyophilized (freeze-dried) as a powder, since they are most stable in this form. For laboratory use, the powder is diluted with bacteriostatic water (BAC water) — this process is called reconstitution. The formula for calculating the resulting concentration:
Concentration (mg/ml) = active substance amount (mg) ÷ BAC water amount (ml)
Volume (ml) = desired substance amount (mg) ÷ concentration (mg/ml)
Units on U-100 syringe scale = volume (ml) × 100
Unit Conversion
| Unit | Equals |
|---|---|
| 1 mg | 1.000 mcg (µg) |
| 1 ml | 100 Einheiten auf U-100-Spritzenskala |
| 0,1 ml | 10 Einheiten auf U-100-Spritzenskala |
| 0,01 ml | 1 Einheit auf U-100-Spritzenskala |
Syringe Scales at a Glance
U-100 syringe scales are commonly used in the lab for precise volume measurement (a scale originally standardized for insulin, where 100 units = 1 ml). Common sizes for measuring liquid volume:
- 1 ml / 100 Einheiten — for larger volumes
- 0,5 ml / 50 Einheiten — for medium volumes, finer scale graduation
- 0,3 ml / 30 Einheiten — for the smallest volumes, highest reading accuracy
Reconstitution Step by Step
- Bring the vial and BAC water to room temperature before use.
- Draw up the desired amount of BAC water with a sterile syringe.
- Let the water run slowly down the inside wall of the vial — do not inject it directly onto the powder.
- Gently swirl the vial, do not shake, until the powder has fully dissolved.
- Store the reconstituted solution protected from light at 2–8 °C and use it promptly.
Practical Examples
BPC-157
10 mg + 2 ml BAC water, target dose 250 mcg → 5 units
TB-500
10 mg + 2 ml BAC water, target dose 500 mcg → 10 units
GHK-Cu
50 mg + 5 ml BAC water, target dose 1000 mcg → 10 units
CJC-1295 without DAC
5 mg + 2 ml BAC water, target dose 300 mcg → 12 units
DSIP
5 mg + 2 ml BAC water, target dose 200 mcg → 8 units
Ipamorelin
5 mg + 3 ml BAC water, target dose 250 mcg → 15 units
Melanotan II (MT-2)
10 mg + 2 ml BAC water, target dose 500 mcg → 10 units
Common Mistakes
- Confusing mg and mcg — 1 mg = 1,000 mcg. Double-check the unit before every calculation.
- Injecting BAC water directly onto the powder instead of along the vial wall — can damage the peptide structure.
- Shaking the vial instead of swirling it.
- Using the wrong syringe scale (e.g. a 1 ml instead of a 0.3 ml scale for very small volumes) — significantly reduces reading accuracy.
- Storing the reconstituted solution at room temperature instead of refrigerated.
Frequently Asked Questions
What does BAC water stand for?
BAC water (bacteriostatic water) is sterile water containing a small amount of benzyl alcohol (0.9%), which inhibits microbial growth and thus allows the diluted solution to stay stable for longer compared to plain sterile water.
Why is the result shown in syringe units?
The U-100 scale is a common laboratory standard for precisely measuring very small liquid volumes. 100 units correspond to 1 ml — the scale makes it easier to measure the smallest amounts accurately.
How long does a reconstituted solution last?
When stored in the refrigerator (2–8 °C) and protected from light, a reconstituted solution typically remains stable for 4–6 weeks. More detailed information can be found in our storage guide.
Can I enter any amount of water?
Yes, using the "Other amount …" option you can enter any BAC water amount — the calculation adjusts automatically.
Glossary
- BAC Water — Bacteriostatic water: sterile water containing a small amount of benzyl alcohol (0.9%), which inhibits microbial growth. This keeps a solution mixed from it stable for longer than with plain sterile water.
- Lyophilisate — A powder obtained through freeze-drying. Peptides are supplied in this form because they are significantly more stable than in dissolved form, and are only reconstituted immediately before use.
- Reconstitution — Dissolving a lyophilisate in a liquid, usually BAC water, to form a ready-to-use solution. The resulting concentration is the active substance amount in the vial divided by the amount of liquid added.
- IU vs. mg/ml — IU (international unit) describes a biological activity and is converted to milligrams differently depending on the substance — there is no single conversion factor across different peptides. mg/ml, by contrast, is a pure mass concentration, independent of biological activity. The two figures are therefore not directly interchangeable.
- U-100 Scale — A scale originally standardized for insulin syringes, where 100 units (IU) correspond to a volume of 1 ml. In the lab it is now used generally for precisely measuring small liquid volumes.