How Much Bacteriostatic Water for an SS-31 10 mg Vial?
A 10 mg vial of SS-31 reconstituted with 2 mL of bacteriostatic water gives a concentration of 5 mg/mL; with 1 mL it gives 10 mg/mL. The calculation depends only on the quantity in the vial and the volume of water added, so the figures below apply to any 10 mg vial.
Voir le produit →There is no single correct volume. Adding more water does not change how much is in the vial. It spreads the same quantity through a larger volume, which changes how many syringe units correspond to a given amount. The tables on this page use volumes that produce round numbers on a U-100 syringe; other volumes work identically as long as the resulting concentration is written on the vial.
Concentration by water volume
Concentration is the quantity in the vial divided by the water volume. A 10 mg vial holds 10 mg whether it receives 1 mL or 5 mL; only the mg/mL figure moves. The right-hand column converts each concentration into the number of U-100 units that contain 1 mg.
| Vial | Bacteriostatic water added | Concentration | Units containing 1 mg |
|---|---|---|---|
| 10 mg SS-31 | 1 mL | 10 mg/mL | 10 units |
| 10 mg | 2 mL | 5 mg/mL | 20 units |
| 10 mg | 3 mL | 3.33 mg/mL | 30 units |
| 10 mg | 5 mL | 2 mg/mL | 50 units |
Before choosing a larger volume, check that the vial has headspace for it. A 10 mL vial of bacteriostatic water reconstitutes five 10 mg vials at 2 mL each.
Reading the concentration on a U-100 syringe
A U-100 insulin syringe is graduated in units, and 100 units equal 1 mL. Units are therefore millilitres multiplied by 100: 0.1 mL is 10 units and 0.25 mL is 25 units. A 0.5 mL syringe carries 50 units and a 0.3 mL syringe carries 30 units on the same scale, with finer markings that make small volumes easier to read.
To find the volume that contains a given amount, divide the amount by the concentration. At 5 mg/mL (a 10 mg vial with 2 mL of water), the volume that contains 1 mg is 1 divided by 5, which is 0.2 mL, or 20 units. The table below runs the same calculation for four arbitrary amounts. They illustrate the arithmetic and nothing else.
| Amount (illustrative) | Volume at 5 mg/mL | U-100 units |
|---|---|---|
| 0.25 mg | 0.05 mL | 5 units |
| 0.5 mg | 0.1 mL | 10 units |
| 1 mg | 0.2 mL | 20 units |
| 2 mg | 0.4 mL | 40 units |
At 10 mg/mL, which the same vial gives with 1 mL of water, every volume in the table moves in proportion: a 1 mg draw measures 10 units instead of 20. Volumes below about 0.1 mL are hard to read accurately on a 1 mL syringe. Either move to a 0.3 mL or 0.5 mL syringe, or reconstitute with more water so that the same mass occupies a larger, more legible volume.
SS-31 is supplied by Vistara Labs as a lyophilised material for research use. The quantities on this page illustrate the arithmetic of dilution and measurement only.
The SS-31 vial
SS-31, also called elamipretide, is a tetrapeptide: four amino acids that bind cardiolipin in the inner mitochondrial membrane. Vistara Labs supplies it as a 10 mg lyophilised vial. The same 10 mg arithmetic covers MOTS-c, the other mitochondrial vial in the catalogue. Certificates of analysis for the catalogue are published on the Résultats de laboratoire page.
SS-31 is built from an alternating pattern of positively charged and aromatic residues, including D-arginine and a modified tyrosine, and that pattern is what lets it cross membranes and settle on cardiolipin. It is also the research name for elamipretide, which received its first FDA approval in late 2025, for Barth syndrome; the approved medicine is a separate product under its own labelling. The trial record, including the misses, is in SS-31 (elamipretide): from research to FDA approval, and the buying questions in buying SS-31 in Canada.
Reconstitution technique
Let the vial reach room temperature, swab both stoppers, and run the measured water slowly down the inside wall of the vial rather than onto the powder. Swirl or tilt gently until the cake dissolves, never shake, and give any remaining powder a few minutes to settle into solution. Label the vial with the date and the concentration, then keep it refrigerated at 2 to 8 °C and protected from light. The full method, with the reason behind each step, is in l'achat d'eau bactériostatique au Canada.
Why the solution should look clear
Properly reconstituted SS-31 forms a clear, colourless solution. Cloudiness, strands or a gel that will not disperse usually mean the water went in too fast or the vial was shaken; haze that appears later points to warm or bright storage. The causes are covered in why peptides gel or go cloudy.
Bacteriostatic water, not sterile water
Bacteriostatic water is sterile water with 0.9% benzyl alcohol, a preservative that allows a refrigerated vial to be accessed more than once; plain sterile water is intended for single access. The difference is explained in bacteriostatic water explained.
Questions fréquentes
How much bacteriostatic water do I add to a 10 mg vial of SS-31?
There is no single correct volume. With 2 mL of bacteriostatic water a 10 mg vial of SS-31 gives 5 mg/mL; with 1 mL it gives 10 mg/mL. Adding more water does not change the quantity in the vial, it spreads it through a larger volume, so write the concentration you chose on the vial.
How many 10 mg vials does a 10 mL vial of bacteriostatic water cover?
A 10 mL vial of bacteriostatic water reconstitutes five 10 mg vials at 2 mL each. Check that the peptide vial has headspace for the volume before choosing a larger one.
How many units on a U-100 syringe contain 1 mg at 5 mg/mL?
At 5 mg/mL (a 10 mg vial with 2 mL of water), the volume that contains 1 mg is 1 divided by 5, which is 0.2 mL, or 20 units. Units are millilitres multiplied by 100, so 0.1 mL is 10 units. The amounts on this page illustrate the arithmetic only.
What should reconstituted SS-31 look like?
Properly reconstituted SS-31 forms a clear, colourless solution. Cloudiness, strands or a gel that will not disperse usually mean the water went in too fast or the vial was shaken; haze that appears later points to warm or bright storage. More on the causes in why peptides gel or go cloudy.
Can I use sterile water instead of bacteriostatic water?
Only for a vial that will be accessed once. Bacteriostatic water is sterile water with 0.9% benzyl alcohol, a preservative that allows a refrigerated vial to be accessed more than once; plain sterile water is intended for single access. Details in bacteriostatic water explained.
How should a reconstituted SS-31 vial be stored?
Refrigerated at 2 to 8 °C, protected from light and labelled with the date and the concentration. Unopened lyophilised vials are kept cold and dark until they are needed. The full storage guide is how to store research peptides.
Work it out for a different vial or concentration
Our calculateur de peptides opens pre-set for a 10 mg vial with 2 mL of water and marks the 1 mg draw of 20 units on a syringe diagram. Change the vial size, water volume, amount or syringe and it recalculates.
Products: SS-31 10 mg et bacteriostatic water 10 mL.
Références
SS-31 (elamipretide) has a mature clinical programme. Mechanistic evidence is strong and human exposure substantial, but efficacy results are mixed and indication-dependent — including trials that missed their primary endpoints.
- Efficacy and Safety of Elamipretide in Individuals With Primary Mitochondrial Myopathy: The MMPOWER-3 Randomized Clinical TrialRandomised, double-blind phase 3 trial (MMPOWER-3), 24 weeks. The primary exercise and fatigue endpoints were not met.
- A randomized crossover trial of elamipretide in adults with primary mitochondrial myopathyRandomised crossover trial in adults with genetically confirmed primary mitochondrial myopathy.
- Effects of Elamipretide on Left Ventricular Function in Patients With Heart Failure With Reduced Ejection Fraction: The PROGRESS-HF Phase 2 TrialRandomised phase 2 trial; 71 patients. No significant improvement in left-ventricular end-systolic volume or ejection fraction versus placebo.
Les liens ouvrent la fiche de l'étude sur PubMed afin que la source puisse être vérifiée directement. Citer une étude ne signifie pas que ses résultats s'appliquent à un autre usage, produit ou mode d'administration. Usage laboratoire uniquement.
