DMSO vs Water: Solvent Properties Comparison
Dimethyl sulfoxide (DMSO) and water are both polar solvents, but they occupy opposite ends of the solvent spectrum in many respects. DMSO's extraordinary skin penetration, cryoprotective properties, and ability to dissolve both polar and nonpolar compounds make it unique among solvents. This comparison highlights when DMSO's unusual properties make it the superior choice — and when water remains the gold standard.
Property Comparison
| Property | DMSO (Dimethyl Sulfoxide) | Water (Deionized) |
|---|---|---|
| Polarity (dielectric constant) | 47 (highly polar) | 80 (extremely polar) |
| Skin Penetration | Exceptional — carries dissolved substances through skin | Minimal — skin is a barrier to water penetration |
| Freezing Point | 18.5 °C (solid at room temp below this) | 0 °C |
| Boiling Point | 189 °C | 100 °C |
| Viscosity | 2.0 cP at 20 °C | 1.0 cP at 20 °C |
| Dissolves Nonpolar Solutes | Yes — amphiphilic, dissolves many organics | Very limited — only dissolves ionic/polar compounds |
| Biological Compatibility | Moderate — cryoprotectant at 10%; toxic at high concentrations | Essential — universal biological solvent |
| Odor | Garlic/oyster-like (perceived after skin contact) | Odorless |
| Reactivity | Mild oxidant; reacts with strong oxidizers and acids | Chemically inert under most conditions |
Safety Comparison
Uses Comparison
Verdict
Frequently Asked Questions
Why does DMSO make you smell like garlic?
DMSO is metabolized in the body to dimethyl sulfide (DMS), which has a strong garlic/oyster odor. It's excreted through breath and skin for up to 72 hours after exposure. This is harmless but socially noticeable.
Can DMSO really carry toxins through skin?
Yes — this is DMSO's most important safety concern. DMSO penetrates the stratum corneum and can carry dissolved chemicals with it. Never handle DMSO with unwashed hands or contaminated gloves. Always work with pure DMSO in a clean environment.
Why is DMSO used for cell freezing?
DMSO at 10% concentration prevents ice crystal formation inside cells during freezing. It penetrates the cell membrane, replaces water, and reduces osmotic shock during thawing. Without DMSO, frozen cells typically have less than 10% viability; with DMSO, viability can exceed 90%.
What gloves should I wear with DMSO?
Nitrile gloves provide the best protection. DMSO penetrates latex rapidly. Double-gloving with nitrile is recommended for extended handling. Butyl rubber offers the highest resistance for prolonged industrial exposure.