Cetylpyridinium bromide

The method developed by Epton [212,213] became the universally accepted method for the analysis of active matter of anionic and cationic surfactants. Epton s method, also known as the two-phase titration, is based on the titration of the anionic surfactant with cetylpyridinium bromide, a cationic surfactant, in the presence of methylene blue as indicator. A solution of the anionic surfactant is mixed with the indicator dissolved in dilute sulfuric acid, followed by further addition of chloroform, and then it is titrated with the cationic surfactant. Methylene blue forms a complex with the anionic salt that is soluble in chloroform, giving the layer a blue color. As the titration proceeds there is a slow transference of color to the water layer until the equivalence point. At the equivalence point colors of the chloroform and water layers are visually the same. On successive additions of titrant the chloroform layer lightens in shade and finally becomes colorless. 

Hexadecylpyridinium chloride (cetylpyridinium chloride) Hexadecylpyridinium bromide (cetylpyridinium bromide) Dioctadecyldimethylammonium chloride... 

Cetylpyridinium bromide, physical properties of, 4 350t Cetylpyridinium chloride, function as ingredient in cosmetics, 7 829t Cetyltrimethylammonium bromide (CTAB) surface area, of silica, 22 371, 386. 

Orienting systems of quasi-ternary mixtures composed of cetylpyridinium chloride/hexa-nol/NaCl [26] and cetylpyridinium bromide/hexanol/NaBr [27] have been reported to form lamellar liquid crystalline phases that allow a large temperature range over which dipolar couplings can be measured. The optimum condition for protein alignment consists of a 1 1.33 (w/w) ratio of cetylpyridinium bromide/hexanol. The residual 2H quad-rupolar splitting of the HOD resonance increases from 5 Hz to 20 Hz as the concentration of the mixture is varied from 30 to 65 mg/mL. These quasi-ternary mixtures are positively charged. 

R = Et) were hydrolysed in micellar solutions of the prepared ketoximes under pseudo-first-order reaction conditions.In the alkaline hydrolysis of / -nitrophenyl ethyl chloromethylphosphonate (254), micellar catalysis by cetylpyridinium bromide is much reduced when KCl and KBr are present. ... 

Surfactant (cetylpyridinium bromide [CPBr]) + hexanol + salt + water... 

A method for purifying certain neutral polysaccharides by precipitation in borate buffer with cetyltrimethylammonium bromide was developed by Stacey and coworkers,118 but it does not appear to have been used for the isolation of galactomannan gums. It has, however, been claimed119 that guar gum and locust-bean gum can be separated by carefully controlled precipitation of the cetylpyridinium bromide complexes by 0.1 M sodium hydroxide. Guar gum is precipitated between pH 7.0 and 8.3, and locust-bean gum between 8.6 and 9.3. 

AA BAA CMC CPB CTAB DM SO IPC MVPQ PAA PDADMAB PEG PIPAA SDS SMA TEMED acrylamide methylene bisacrylamide critical micelle concentration cetylpyridinium bromide cetyltrimethylammonium bromide dimethylsulfoxide interpolymer complex methylvinylpiridine units quaternized by dimethyl sulfate poly(acrylamide) poly(diallyldimethylammonium bromide) polyethylene glycol) poly(isopropylacrylamide) sodium dodecyl sulfate sodium methacrylate tetramethylethylenediamine... 

The objects of our experimental study were the networks of PMAA with different degree of neutralization and also networks of copolymers of AA or methacrylamide with SMA. Cetylpyridinium bromide (CPB) was employed as the surfactant. 

Alkyl (Me, Et, n-Pr, n-Bu), alkyldimethyl, and alkyltrimethylammonium bromides retard the neutral hydrolysis of 1-benzoyl-1,2,4-triazole (190) to benzoic acid and the triazole (191).162 This effect is attributed to a dominant stabilization of the initial state through hydrophobic interactions with the co-solute. The effects of cetylpyridinium bromide on the hydrolysis of 2,4-dinitrochlorobenzene by hydroxide ion in water have been reported.163... 

Chloroalkanes.1 The conversion of primary alcohols to 1-chloroalkanes with aqueous hydrochloric acid is not useful because of mediocre yields (30-60%). The rate and yield of this reaction are improved considerably by use of a surfactant such as cetyltrimethylammonium bromide or cetylpyridinium bromide. 

A blended composition for facilitating delivery of a biologically active conjugated material was prepared by Kabanov [6] and consisted of a block copolymer of ethylene oxide and acrylic acid salt of cetylpyridinium bromide, (II). 

In addition to divalent metal cations, trivalent and tetravalent cations (i.e. ln +, Ga +, Sb +, and Sn +) were also effective as linking agents to organize [Ge4Sio]" clusters to form hexagonally ordered mesostractures. In this case, cetylpyridinium bromide was nsed as the surfactant, and formamide served as the solvent. The mesophases made with Ga + and Sb + showed intense visible photoluminescence at77K. 

Ge4Sio]" and [Fe4S4CLi] clusters was synthesized from a formamide solution containing the surfactant cetylpyridinium bromide. ... 

The electrochemical behavior of ascorbic acid (1) and uric acid (3) in the presence of micelles and their selective determination were investigated. Aqueous cetylpyridinium bromide (cpb) and sodium dodecylbenzenesulfonate (sdbs) miceUar solutions have been used. The oxidation peak potentials for 1 and 3 are separated by 270 mV in the presence of cpb in aqueous phosphate buffer solution (pH 6.8), thus allowing their selective determination, as well as the selective determination of 3 in the presence of excess of 1. The method is simple, inexpensive and rapid with no need to modify the electrode surface by tedious procedures, and it was applied to 3 determination in samples of human urine and serum. Abnormal levels of uric acid in urine and serum are symptomatic of several diseases (gout, hyperuricaemia and Lesch-Nyhan syndrome) . 

The ratio of the slope above to the slope below the cmc provided an estimate of P [7]. The binding constant was also used to estimate the concentration of alcohol in the bulk phase. Time resolved fluorescence quenching of dimethylnaphthalene by cetylpyridinium bromide solubilized in the micelles was used to obtain estimates of the mean aggregation number of the surfactant in the mixed micelles. 

Synonyms Aceloquat CPB BromoceP, Cetapharm-, Cetasoh, N-cetylpyridinium bromide hexadexylpyridinium bromide Nitrogenoh, Seprison Sterogenol. 

Carbon dioxide-free water Cationic emulsifying wax Ceratonia extract Cetylpyridinium bromide Chlorhexidine acetate Chlorhexidine gluconate Chlorhexidine hydrochloride Chlorodifluoromethane Chlorophenoxyethanol Com syrup solids m-Cresol o-Cresol p-Cresol... 

A variety of weak liquid crystalline media have been used to align carbohydrates. Examples include Pfl phage,147-150 filamentous bacteriophage fd,151 C12E5/ -hexanol,77,152-154 C8E5/ -octanol,155 cetylpyridinium bromide / -hexanol /NaCl,73,156-158 DMPC/DHPC (dimyristoyl-phosphatidyl choline / dihexanoyl-... 

Other cationic surfactants, cetylpyridinium bromide (CP) [27], and Zephiramine [26] have been recommended for determining Ga in a ternary system with ECR. 

Trace amounts of Th in geological samples were determined after conversion into molybdothoric acid and reaction with basic dyes [4]. Thorium in ores and minerals was determined using the ternary purple-coloured complex formed between Th(IV), bromocresol orange and cetylpyridinium bromide (X = 560 nm e = 9.2 x 10 1 mof cm ) [5]. 

In the photopolymerisation of methyl methacrylate induced by mixtures of chloroacetic acid derivatives and dimethylaniline the kinetics were found to be influenced by the degree of substitution of the chlorine atoms while the initiation occurred through a complex S. Ethyl aluminium sesquichloride has been found to induce the photocopolymerisation of 9-vinylanthracene with methyl methacrylate at -20°c while photochromic polymers have been made by reacting para-bromoazobenzene with ethylene gas O. Surface active N-cetylpyridinium bromide and chloride have been found to... 

Two-phase titration is usually less sensitive to interference from other foreign (nonsurfactant) species. When applied to anionic surfactant systems, two-phase titration is primarily used for the analysis of alkyl sulfates and sulfonates. Typical titrants in these applications are solutions of cetylpyridinium bromide, cetyltrimethylammonium bromide, and benzyldimethylalkyl (C12 or C14) ammonium chloride. The most accurate results are, however, obtained with p-tert-octyl-phenoxy-ethoxy-ethyl-dimethyl-benzylammonium chloride, also known under the commercial name of Hyamine 1622. The structure of Hyamine 1622 is shown in Fig. 11-32,a. 

Another group of complexing agents, especially useful for charged polysaccharides, are such quarternary ammonium salts as cetyltrimethyl-ammonium bromide or cetylpyridinium bromide. Scott has summarized the work in this field. Acidic polysaccharides form insoluble complexes... 

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