Reconstitution & Storage

How lyophilised material is brought into solution and kept stable. Laboratory reference only: this page covers solvent handling, concentration arithmetic and storage conditions, and nothing else.

Bringing material into solution

  1. 1

    Bring the vial to room temperature

    Take the lyophilised vial out of cold storage and let it stand until it reaches room temperature. Cold glass draws condensation, and a temperature gradient slows dissolution.

  2. 2

    Calculate the volume before adding anything

    Decide the final concentration first, then derive the solvent volume from it. A 10 mg vial brought to 2 ml gives 5 mg/ml; the same vial brought to 1 ml gives 10 mg/ml. The calculator does this arithmetic for every Milo-Lab vial size.

  3. 3

    Add the solvent slowly against the glass wall

    Direct the stream onto the inner wall of the vial rather than onto the lyophilised cake. Peptides are surface-active and shear-sensitive; a stream hitting the powder directly causes foaming and can denature material.

  4. 4

    Swirl, never shake

    Rotate the vial gently until the solution is clear. Shaking introduces air and mechanical stress, both of which degrade peptide integrity. Full dissolution normally takes under a minute.

  5. 5

    Inspect the solution

    A correctly reconstituted solution is clear and free of visible particles. Cloudiness, fibres or persistent foam indicate a problem with the solvent, the temperature or the material.

The arithmetic for every vial size in the catalogue is in the reconstitution calculator.

Storage conditions

Lyophilised, unopened

Minus 20 degrees Celsius, protected from light. Stable for the period stated on the certificate of analysis, usually 24 to 36 months.

Lyophilised, short term

Two to eight degrees Celsius is acceptable for a few weeks where freezer space is unavailable. Avoid temperature cycling.

Reconstituted

Two to eight degrees Celsius, protected from light. The usable period depends on the compound and the solvent; bacteriostatic water extends it relative to plain sterile water.

Freeze-thaw

Avoid repeated cycles of the reconstituted solution. Each cycle costs material through aggregation and adsorption to the vial wall.

Questions

Which solvent is used for reconstitution?

Bacteriostatic water is the common choice because its benzyl alcohol content inhibits bacterial growth once the stopper has been punctured. Some compounds are degradation-sensitive and are handled in dilute acetic acid instead; the product page states this where it applies.

How much solvent does a vial take?

That follows from the concentration you want, not from the vial. Enter the vial amount and the final volume in the reconstitution calculator and it returns the concentration and the volume per U-100 marking.

Why does the solution have to stay cold?

Peptides in solution degrade through hydrolysis, oxidation and aggregation, all of which accelerate with temperature. Cold storage slows every one of these pathways.

What does the certificate of analysis cover?

Purity by HPLC, identity by mass spectrometry, and the storage period the batch was tested for. It is available on request before ordering.

All Milo-Lab material is supplied for laboratory research use only and is not for human or veterinary use. Nothing on this page is a recommendation for use in humans.