Peptide Calculator: reconstitution and vial concentration

How the peptide calculator works

The calculator helps with preparation in the laboratory: it shows what concentration results when a lyophilised peptide is reconstituted with a specific amount of solvent and which volume contains the amount of peptide you need. It is intended exclusively for laboratory research.

Basic formula

Concentration (mg/mL) = amount of peptide in the vial (mg) ÷ volume of solvent (mL)
Volume (mL) = amount of peptide you need (mg) ÷ concentration (mg/mL)

Concentration table

Vial	1 mL of solvent	2 mL of solvent	3 mL of solvent
2 mg	2 mg/mL	1 mg/mL	0.67 mg/mL
5 mg	5 mg/mL	2.5 mg/mL	1.67 mg/mL
10 mg	10 mg/mL	5 mg/mL	3.33 mg/mL
15 mg	15 mg/mL	7.5 mg/mL	5 mg/mL
30 mg	30 mg/mL	15 mg/mL	10 mg/mL

For somatropin the amount is given in international units (IU); according to the WHO standard, 1 mg corresponds to approximately 3 IU.

Which solvent?

For most peptides bacteriostatic water 10 ml is used and for the more sensitive ones Peptide Matrix Water. Some, such as IGF-1 LR3, are reconstituted in 0.6% acetic acid. The differences are explained in the article Bacteriostatic water, acetic acid or matrix water.

Storage after reconstitution

Reconstituted solutions are stored at 2–8 °C, protected from light.

All information relates to laboratory work. The products are intended exclusively for research and not for human use.

1. 1. Amount in vial (mg)
2. 2. Solvent added (mL)
3. 3. Amount per sample (mg)

Calculator information

Laboratory reconstitution calculator: enter the amount of peptide in the vial (mg) and the volume of solvent you added (mL) to get the concentration (mg/mL and µg/µL). Enter the amount each sample requires (mg) to calculate the solution volume in mL and µL. For laboratory research use only.

Quick conversions

• 1 mg = 1000 µg
• 1 mL = 1000 µL
• 1 mg/mL = 1 µg/µL

Reconstitution examples

10 mg vial + 2 mL solvent

Concentration 5 mg/mL (5 µg/µL). For 1 mg per sample: 0.2 mL (200 µL).

5 mg vial + 1 mL solvent

Concentration 5 mg/mL (5 µg/µL). For 0.5 mg per sample: 0.1 mL (100 µL).

Frequently asked questions

How are lyophilized peptides reconstituted?

Add the sterile solvent slowly along the wall of the vial. Do not shake: swirl gently and wait 10–15 minutes at room temperature until the solution is clear.

What is the difference between mg and µg?

1 mg = 1000 µg. The calculator gives the concentration in mg/mL, which corresponds numerically to µg/µL.