Cetrimonium bromide
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Preferred IUPAC name
N,N,N-Trimethylhexadecan-1-aminium bromide | |
Other names
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3D model (
JSmol ) |
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ChEBI | |
ChEMBL | |
ChemSpider | |
ECHA InfoCard
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100.000.283 |
KEGG | |
PubChem CID
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UNII | |
CompTox Dashboard (EPA)
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Properties | |
C19H42BrN | |
Molar mass | 364.45 g/mol |
Appearance | white powder |
Melting point | 237 to 243 °C (459 to 469 °F; 510 to 516 K) (decomposes) |
Pharmacology | |
D08AJ02 (WHO) | |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Cetrimonium bromide, also known with the abbreviation CTAB, is a
It is one of the components of the topical antiseptic cetrimide.[1] The cetrimonium (hexadecyltrimethylammonium) cation is an effective antiseptic agent against bacteria and fungi. It is also one of the main components of some buffers for the extraction of DNA.[2] It has been widely used in synthesis of gold nanoparticles (e.g., spheres, rods, bipyramids), mesoporous silica nanoparticles (e.g., MCM-41), and hair conditioning products. The closely related compounds cetrimonium chloride and cetrimonium stearate are also used as topical antiseptics and may be found in many household products such as shampoos and cosmetics. CTAB, due to its relatively high cost, is typically only used in select cosmetics.
As with most surfactants, CTAB forms micelles in aqueous solutions. At 303 K (30 °C) it forms micelles with aggregation number 75–120 (depending on method of determination; average ~95) and degree of ionization, α = 0.2–0.1 (fractional charge; from low to high concentration).[3] The binding constant (K°) of Br− counterion to a CTA+ micelle at 303 K (30 °C) is c. 400 M-1. This value is calculated from Br− and CTA+ ion selective electrode measurements and conductometry data by using literature data for micelle size (r = ~3 nm)[citation needed], extrapolated to the critical micelle concentration of 1 mM[citation needed]. However, K° varies with total surfactant concentration so it is extrapolated to the point at which micelle concentration is zero.[citation needed]
Applications
Biological
Cell lysis is a convenient tool to isolate certain macromolecules that exist primarily inside of the cell. Cell membranes consist of hydrophilic and lipophilic endgroups. Therefore, detergents are often used to dissolve these membranes since they interact with both polar and nonpolar endgroups. CTAB has emerged as the preferred choice for biological use because it maintains the integrity of precipitated DNA during its isolation.[4] Cells typically have high concentrations of macromolecules, such as glycoproteins and polysaccharides, that co-precipitate with DNA during the extraction process, causing the extracted DNA to lose purity. The positive charge of the CTAB molecule allows it to denature these molecules that would interfere with this isolation.[5]
Medical
CTAB has been shown to have potential use as an apoptosis-promoting anticancer agent for head and neck cancer (HNC).[6] In vitro, CTAB interacted additively with γ radiation and cisplatin, two standard HNC therapeutic agents. CTAB exhibited anticancer cytotoxicity against several HNC cell lines with minimal effects on normal fibroblasts, a selectivity that exploits cancer-specific metabolic aberrations. In vivo, CTAB ablated tumor-forming capacity of FaDu cells and delayed growth of established tumors. Thus, using this approach, CTAB was identified as a potential apoptogenic quaternary ammonium compound possessing in vitro and in vivo efficacy against HNC models. CTAB is also recommended by the World Health Organisation (WHO) as a purification agent in the downstream vaccine processing of polysaccharide vaccines.[7]
Protein electrophoresis
Glycoproteins form broad, fuzzy bands in SDS-PAGE (Laemmli-electrophoresis) because of their broad distribution of negative charges. Using positively charged detergents such as CTAB will avoid issues associated with glycoproteins. Proteins can be blotted from CTAB-gels in analogy to western blots ("eastern blot"), and Myelin-associated high hydrophobic protein can be analyzed using CTAB 2-DE.[citation needed]
DNA extraction
CTAB serves as an important surfactant in the DNA extraction buffer system to remove membrane lipids and promote cell lysis. Separation is also successful when the tissue contains high amounts of polysaccharides.[2] CTAB binds to the polysaccharides when the salt concentration is high, thus removing polysaccharides from solution. A typical recipe can be to combine 100 mL of 1 M Tris HCl (pH 8.0), 280 mL 5 M NaCl, 40 mL of 0.5 M EDTA, and 20 g of CTAB then add double distilled water (ddH2O) to bring total volume to 1 L.
Nanoparticle synthesis
Surfactants play a key role in nanoparticle synthesis by adsorbing to the surface of the forming nanoparticle and lowering its surface energy.[8][9] Surfactants also help to prevent aggregation (e.g. via DLVO mechanisms).
Au nanoparticle synthesis
Gold (Au) nanoparticles are interesting to researchers because of their unique properties that can be used in applications such as catalysis, optics, electronics, sensing, and medicine.[10] Control of nanoparticle size and shape is important in order to tune its properties. CTAB has been a widely used reagent to both impart stability to these nanoparticles as well as control their morphologies. CTAB may play a role in controlling nanoparticle size and shape by selectively or more strongly binding to various emerging crystal facets.
Some of this control originates from the reaction of CTAB with other reagents in the gold nanoparticle synthesis. For example, in aqueous gold nanoparticle syntheses,
However, CTA+-AuCl−
4 should not be called a complex, electrostatic interaction of quaternary ammonium cation with AuCl−
4 results in formation of an ion pair at best. CTA+ does not have any donating centers which can form a coordination complex with Au(III) metal centers.
Mesoporous materials
CTAB is used as the template for the first report of ordered
Toxicity
CTAB has been used for applications from nanoparticle synthesis to cosmetics. Due to its use in human products, along with other applications, it is essential to be made aware of the hazards this agent contains. The Santa Cruz Biotechnology, Inc.
CTAB along with other quaternary ammonium salts have frequently been used in cosmetics at concentrations up to 10%. Cosmetics at that concentration must only be used as rinse-off types such as shampoos. Other leave-on cosmetics are considered only safe at or below 0.25% concentrations. Injections into the body cavity of pregnant mice showed embryotoxic and teratogenic effects. Only teratogenic effects were seen with 10 mg/kg doses, while both effects were seen at 35 mg/kg doses. Oral doses of 50 mg/kg/day showed embryotoxic effects as well.[16] Similar tests were completed by giving rats 10, 20, and 45 mg/kg/day of CTAB in their drinking water for one year. At the 10 and 20 mg/kg/day doses, the rats did not have any toxic symptoms. At the highest dose, the rats began experiencing weight loss. The weight loss in the male rats was attributed to less efficient food conversion. The tests showed no microscopic alterations to the gastrointestinal tract of the rats.[18]
Other toxicity tests have been conducted using incubated human skin HaCaT keratinocyte cells. These human cells were incubated with gold nanorods that were synthesized using seed-mediated, surfactant-assisted growth of gold nanoparticles. Gold nanoparticles are shown to be nontoxic, however once the nanoparticles are put through the growth solutions, the newly formed nanorods are highly toxic. This large increase in toxicity is attributed to the CTAB that is used in the growth solutions to cause anisotropic growth.[19] Experiments also showed the toxicity of bulk CTAB and the synthesized gold nanorods to be equivalent. Toxicity tests showed CTAB remaining toxic with concentrations as low as 10 μM. The human cells show CTAB being nontoxic at concentrations less than 1 μM. Without the use of CTAB in this synthesis, the gold nanorods are not stable; they break into nanoparticles or undergo aggregation.[19]
The mechanism for
See also
- Behentrimonium chloride – A C25 structural analogue
- Cetrimonium chloride – The corresponding chloride salt
References
- S2CID 3105149.
- ^ PMID 20147112.
- ISSN 0001-4842.
- PMID 22467363.
- PMID 20147112.
- S2CID 7767460.
- ^ "CTAB in polysaccharide (bacterial) vaccines". 22 October 2021. Archived from the original on 2017-05-17.
- PMID 20596462.
- ^ "Surfactants: Types and uses" (PDF).
- .
- PMID 23298582.
- ISSN 0743-7463.
- S2CID 4249872.
- ^ "Cetyltrimethylammonium Bromide" (PDF). scbt.com. Retrieved 7 April 2024.
- ^ a b "Santa Cruz Biotechnology, Inc. MSDS" (PDF). April 23, 2011.
- ^ S2CID 91433062.
- ^ "Sigma-Aldrich MSDS" (PDF). September 29, 2008.
- S2CID 21556825.
- ^ PMID 19204862.
- doi:10.7282/t3x63kms.
Further reading
- Merck Index, 11th Edition, 1989.
- Drug information