CTAB returns for an encore performance, the silky-smooth cationic surfactant that keeps biomolecules in line like a very tiny nightclub security guard.
Here is a clean and complete specification sheet for Cetyltrimethylammonium Bromide:
Cetyltrimethylammonium Bromide (CTAB) – Specifications
Chemical Identity
| Parameter | Value |
|---|---|
| Molecular formula | C₁₉H₄₂BrN |
| Molecular weight | ~364.45 g/mol |
| CAS Number | 57-09-0 |
| EC Number | 200-311-3 |
| IUPAC name | Hexadecyl(trimethyl)azanium bromide |
Synonyms
• Cetrimonium bromide
• Hexadecyltrimethylammonium bromide
• Cationic surfactant C16
Physical Characteristics
| Property | Specification |
|---|---|
| Appearance | White crystalline powder or waxy flakes |
| Odor | Faint surfactant odor |
| Solubility | Soluble in warm water and alcohols |
| Melting point | 242–247°C (decomposition begins) |
| pH (1% solution) | 6.0–8.0 |
| CMC (in water, 25°C) | ~0.9 mM |
| Charge | Positive (quaternary ammonium) |
Functional Profile
• Strong cationic detergent and disinfectant
• Common in plant DNA extraction buffers to remove polysaccharides
• Emulsifier and antiseptic in cosmetics and pharmaceuticals
• Template agent for nanoparticle synthesis
Purity Grades Available
• ≥98% general laboratory grade
• ≥99% molecular biology grade
• Low endotoxin options for nucleic acid workflows
Storage & Stability
• Keep tightly sealed in a cool, dry place
• Stable under typical lab conditions
• Avoid moisture, light, and oxidizers
Safety Highlights
• Corrosive to skin and eyes
• Harmful if swallowed or inhaled
• PPE recommended: gloves, coat, eye protection
• Environmental hazard in aquatic systems
• Hazard statements: H302, H314, H400
Regulatory Notes
• Quaternary ammonium compound
• Dispose of as hazardous chemical waste
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