What Is Dimethyl Sulfoxide (DMSO)?
DMSO (dimethyl sulfoxide, (CH3)2SO) is a polar aprotic solvent with exceptional solubility power for both polar and nonpolar compounds. It is widely used in research for reconstituting small-molecule compounds, cryopreservation of cell lines, and as a vehicle in pharmacological assays. DMSO is hygroscopic and has a freezing point of 18.5°C.
Side-by-Side Specification
| Criterion | Bacteriostatic Water (BW-10) | DMSO |
|---|---|---|
| Solvent Type | Aqueous | Polar aprotic organic |
| Solubility Range | Hydrophilic compounds only | Hydrophilic + hydrophobic |
| Freezing Point | ~0°C | 18.5°C (solid at room temp in winter) |
| Preservative | 0.9% Benzyl Alcohol | None (self-stable) |
| Cellular Effects | Inert at use concentrations | Penetrates cell membranes — vehicle effect |
| Typical Final Concentration | 100% diluent | <0.1% in assays (vehicle) |
When to Use Bacteriostatic Water
Use bacteriostatic water when reconstituting hydrophilic compounds — most research peptides, water-soluble proteins, and salts of biologically active compounds.
View BAC Water Depot 10 mL specification · single vials from $9.99, bulk from $6.49 per vial.
When to Use DMSO
Use DMSO when the compound documentation specifies it — typically small-molecule hydrophobic compounds, certain inhibitor stocks, or kinase substrate reconstitution. Always dilute DMSO stocks into aqueous buffer at the assay step to keep final DMSO concentration <0.1%.
Frequently Asked Questions
Can I mix bacteriostatic water and DMSO for partially soluble compounds?
Yes — DMSO/water co-solvent systems are common for compounds with intermediate solubility. Typical protocols dissolve in DMSO first then dilute into bacteriostatic water at a defined final DMSO percentage. Always check the compound's published reconstitution protocol.
Does DMSO require a preservative like benzyl alcohol?
No. DMSO itself is bacteriostatic at typical research concentrations and stable at room temperature.
Why prefer water-based reconstitution when possible?
DMSO has measurable biological effects on cells (membrane penetration, vehicle effects in assays). Water-based reconstitution with bacteriostatic water introduces no such confounds, so it is preferred whenever the compound's solubility allows.
Order Direct
Research-Grade Bacteriostatic Water · From $9.99
ISO 9001:2015 USA-manufactured. Three independent labs verify every production lot. CoA available per lot.
