What Dimethyl Sulfoxide Is
Dimethyl sulfoxide, commonly called DMSO, is a colourless liquid with the CAS number 67-68-5 and the molecular formula C2H6OS. Its molecular weight is about 78.13 and it has a strong, distinctive odour. DMSO is remarkable for its solvency: it dissolves a wide range of organic and inorganic substances, including both polar and non-polar compounds.
That broad solubility range is the foundation of its many roles in the chemical, pharmaceutical, industrial and scientific fields. DMSO also has a high boiling point and good thermal stability, which lets it be recovered and reused in continuous processes.
Role in the Chemical and Industrial Sectors
In the chemical industry DMSO is used as a laboratory and industrial solvent for gases, synthetic fibres, paints, hydrocarbons, salts and natural products. Industrial-grade DMSO is used in paint and coating formulations, in adhesive production and in polymer processing, where it acts as a solvent that aids formulation and processing.
Because DMSO can be distilled and returned to the process, it suits large-scale continuous operations where solvent recovery drives the economics. Typical technical duties include:
Solvent for polymer spinning and polymer processing
Carrier solvent in paints, coatings and adhesive formulations
Cleaning and stripping agent in electronics and precision parts production
Formulation solvent for agrochemical actives
Reaction medium for organic synthesis at elevated temperature
Role in Pharmaceuticals and Medicine
Pharmaceutical-grade DMSO penetrates human skin with little effect on the underlying tissue, so it is used in certain transdermal drug delivery systems, where it helps active substances cross the skin barrier. One approved prescription product containing DMSO is used for the relief of symptoms of chronic interstitial cystitis, a painful bladder condition.
In the medical literature DMSO is described as having anti-inflammatory, local anaesthetic, weak bacteriostatic and diuretic properties, and it has been applied topically in the management of burns, pain, sprains and incision healing. These uses are limited to approved drug products and medical supervision; DMSO is not a general-purpose medicine and self-treatment is not recommended.
Role in Scientific Research and Cryopreservation
In research laboratories DMSO is a standard solvent for chemical reactions and for nuclear magnetic resonance spectroscopy. It is also widely used as a cryoprotectant for freezing and storing living cells, including stem cells, without damaging them.
Its ability to dissolve both hydrophilic and lipophilic compounds makes it a convenient vehicle for preparing stock solutions of drugs and natural products in biological experiments. Researchers value DMSO for its broad solvent range, its stability and its relatively low toxicity in controlled laboratory use.
Purity Grades and Safe Handling
DMSO is supplied in different purity grades that must match the application. Industrial-grade DMSO suits paints, coatings, adhesives, electronics cleaning and agrochemical formulations, where technical performance is the priority. Pharmaceutical-grade DMSO meets much stricter purity specifications because it may be used in drug products that come into contact with the human body.
| Grade | Typical use | Key requirement |
|---|---|---|
| Industrial grade | Coatings, adhesives, polymer processing, cleaning | Consistent solvency and recovery performance |
| Pharmaceutical grade | Drug products, transdermal delivery | Tight limits on residual impurities and water |
Because DMSO penetrates the skin readily and can carry dissolved substances with it, handlers must wear protective gloves made of materials that resist DMSO, work in ventilated areas and follow the safety data sheet. Storage should be sealed, cool and away from strong oxidisers.
Frequently Asked Questions
Q: What is the role of dimethyl sulfoxide DMSO liquid?
DMSO serves as a versatile solvent in chemical, pharmaceutical, industrial and research applications, and as a penetration enhancer in approved transdermal drug products.
Q: What is the CAS number of DMSO?
The CAS number of dimethyl sulfoxide is 67-68-5, and its molecular formula is C2H6OS.
Q: Is DMSO used in medicine?
Pharmaceutical-grade DMSO is approved for relief of symptoms of interstitial cystitis, and DMSO is used in certain transdermal delivery systems under medical supervision.
Q: Can DMSO dissolve both polar and non-polar substances?
Yes. DMSO dissolves a wide range of organic and inorganic compounds, which is why it is so widely used across industries.
Q: What precautions are needed when handling DMSO?
Because DMSO penetrates the skin and can carry dissolved substances into the body, use resistant gloves, good ventilation and eye protection.
Q: What is the molecular formula of DMSO?
The molecular formula of dimethyl sulfoxide is C2H6OS, with a molecular weight of about 78.13.