Cetyltrimethyl ammonium bromide CTAB

Systems and materials. The reaction was carried out at several compositions in an ionic and in a nonionic system. The ionic system consisted of an emulsifier (49.6 wt % cetyltrimethyl ammonium bromide (CTAB)/50.4% n-butanol), hexadecane, and water. The nonionic emulsifier consisted of 65.7% polyoxyethylene (10) oleyl ether (Brij 96) and 34.4% n-butanol, again with hexadecane and water. In both systems, mlcroemulslon (pE) compositions used were obtained by diluting an initial 90 weight percent (%) emulsifler/10% oil mixture with varying amounts of water. Micro-emulsion samples thus obtained had final compositions of 30 to 80% water. Phase maps describing these systems have been published (10-11). 

Since N will be larger than S+, all anionic surfactants are negatively charged. Similarly, cationic micelles will be positively charged. For instance, the cationic surfactant cetyltrimethyl ammonium bromide (CTAB), we have following equilibrium in micellar solutions ... 

Contrary to hydrotropes, micelle-forming surfactants spontaneously self-aggregate cooperatively above the critical micelle concentration (cmc) even in the absence of solubilizate. Typical examples of micelle-forming surfactants include sodium dode-cylsulfate (SDS), dodecyltrimethylammonium bromide (DTAB), cetyltrimethyl-ammonium bromide (CTAB), and heptaoxyethylene dodecyl ether (C12E7) (Scheme 2). 

Cetyltrimethyl ammonium bromide (CTAB) dodecyltrimethyl ammonium bromide (DTAB) tetradecyltrimethyl ammonium bromide (TTAB) trioctyl-methyl ammonium chloride (TOMAC) N-benzyl-N-dodecyl-hf-bis(2-hy-droxy ethyl) ammonium chloride (BDBAC) cetyl pyridinimn chloride (CPC) quaternary ammonium salt with carbon atoms of R ranging from 8-10 (CHj Rj N+ CL) (Aliquat 336)... 

Several approaches to develop an improved JEV vaccine are in progress in various laboratories. Of these, immunization of mice with plasmid DNA encoding JEV envelope (E) protein has shown great promise. The technology, developed by Kaur et al. [232], involved the adsorption of DNA onto cetyltrimethyl-ammonium bromide (CTAB) containing cationicpoly(lactide-co-glycolide) (PLG) microspheres. 

The vast majority of miniemulsion polymerizations reported in the literature have been stabilized with anionic surfactants, probably because of the widespread application of anionic surfactants in macroemulsion polymerization, and due to their compatibility with neutral or anionic (acid) monomers and anionic initiators. However, Landfester and coworkers [70, 71] have used the cationic surfactants cetyltrimethyl ammonium bromide (CTAB) and cetyltri-methyl ammonium tartrate for the production of styrene miniemulsions. They report that these surfactants produce similar particle sizes to anionic surfactants used at the same levels. Bradley and Grieser [72] report the use of dodecyltrimethyl ammonium chloride for the miniemulsion polymerization of MMA and BA. 

All chemicals were obtained reagent grade from Aldrich Chemical Company. The liquids were passed through a column of Woelm Act. I alumina for purification, and were subsequently dried and storaged over 4A molecular sieves. The cetyltrimethyl-ammonium bromide (CTAB) was twice recrystallized from acetone. 

MCM-41 and Mo containing MCM-41 materials were synthesized under hydrothermal conditions at 388 K in a static stainless steel autoclave. In a typical synthesis of Mo-MCM-41, to a 25% aqueous solution of cetyltrimethyl ammonium bromide (CTAB) (S.D.Fine Chem.) 4gms. of 10% aqueous tetramethyl ammonium hydroxide (TMAOH) (S.D.Fine Chem.) was... 

Finally, the present reaction proceeds smoothly only in water, without using any organic solvents, and in the presence or absence of a small amount of a cationic surfactant, cetyltrimethyl-ammonium bromide (CTAB). " ... 

Analysis of histones is frequently carried out in the presence of detergents which may bind to them. Binding of the nonionic detergent Triton X-100 to histones from calf thymus can be analysed by gel chromatography. The binding of Triton to histones was abolished if 8 M urea was present in 0.01 M HCl or 0.9 M acetic acid [110]. Subsequently [111], the effects of the cationic detergent cetyltrimethyl ammonium bromide (CTAB), and the anionic detergent sodium dodecyl sulphate (SDS), in GPC and electrophoresis were compared. The results showed that, in the presence of CTAB, the values of the retardation and distribution coefficients were linear in respect to the molecular mass of histones, while in the presence of SDS, deviations from this type were observed. 

The most common surfactants used in MECC are anionic and cationic, for example, SDS and cetyltrimethyl ammonium bromide (CTAB). Subtle changes in the solute miscelle interactions giving enhanced resolution have been achieved by using a variety of organic modifications, e.g. chiral selectors such as cyclodextrins and crown ethers [88] and quaternary anions for ion pairing. 

In one of the reported works, TOPO-coated CdSe QDs were dispersed in a micellar solution of surfactant, which could be subsequently swollen by monomer [307], In detail, a toluene solution of CdSe was first added dropwise to a micellar solution of cetyltrimethyl ammonium bromide (CTAB). Then, a mixture of styrene, DVB, AA, and AIBN was added dropwise at 0°C. Finally, the system was heated to 70°C for 20 h. Submicrometer particles were prepared with an effective incorporation of hydrophobic TOPO-coated CdSe into carboxylic functionalized and crosslinked PS particles. The QD-tagged PS particles were then coated with a fluorescent silica shell through TEOS addition. Particle sizes ranging from 300 nm to 20pm were produced, depending on the recipe used for the synthesis. However, the solid content was quite low and there was no information about the amount of QDs incorporated. 

A wound-healing substance was produced with PVP—water-soluble, biocompatible biopolymer—and the active ingredient (cetyltrimethyl ammonium bromide [CTAB] or cetylp5n ridinum chloride [CPC]] as an organic material. It also has a potential drug release capacity due to its hydrophilic properties. 

Applications related to vanadium determination and micellar media can also be found. Different oxidation states of vanadium have been determined at pH 5 using gallic acid in a cationic micellar solution of cetyltrimethyl ammonium bromide (CTAB). 

Cetyltrimethyl ammonium bromide (CTAB, cationic) Scheme 3.38 Commonly employed surfactants... 

A library of spiro[indole-thiazolidinones] (158) was prepared sonochemically by a three-component reaction in an aqueous medium in the presence of cetyltrimethyl-ammonium bromide (CTAB) as a phase-transfer catalyst (Dandia et al. 2011b). The reaction of isatins (155), aryl or heteroaryl amines (156), and a-mercaptocarboxylic acids (157) under ultrasound for 40-50 min afforded the target molecules in good to excellent yields (80%-98%) (Scheme 8.51). 

Epoxidation of 3-aroylmethylene-indole-2-ones (173) with 30% aqueous hydrogen peroxide using cetyltrimethyl ammonium bromide (CTAB) as a phase-transfer catalyst under ultrasound irradiation afforded spiro[indole-3,2-oxiranes] derivatives (174) in 90%-97% yields (Scheme 8.55). The lead compounds showed potent antimicrobial activity and antioxidant properties (Dandia et al. 2011a). 

Pine Tree extraction buffer see Note 1) 2 % cetyltrimethyl ammonium bromide (CTAB), 2 % polyvinylpyrrolidone (K30), 100 mM Tris-HCl (pH 8.0), 25 mM EDTA, 2.0 M NaCl, 0.5 g/L spermidine, 2 % beta-mercaptoethanol. (Heat the extraction buffer to dissolve all components except the beta-mercaptoethanol and mix well. Aliquot 5 mL into the 15 mL tubes and add the BME just prior to use.)... 

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