Cetylpyridinium bromide, micelle

R. A. Shagidullina, L. Ya. Zakharova, L. A. Kudryavtseva, The effects of cetylpyridinium bromide micelles on the kinetics of alkaline hydrolysis of aUcyl p-nitrophenyl chloromethyl-phosphonate, Russ. Chem. Bull., 1999, 48, 278-283. 

Porte G, AppeU J, Poggi Y (1980) Experimental investigations on the flexibility of elongated cetylpyridinium bromide micelles. J Phys Chem 84 3105-3110... 

Porte G, AppeU J (1981) Growth and size distributions of cetylpyridinium bromide micelles in high ionic strength aqueous solutions. J Phys Chem 85 2511-2519... 

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 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. 

Typical examples of giant worm-like micelles are cationic surfactants cetylpyridinium bromide (CPyB) or cetylpyridinium cloride (CPyC) [76-79] with added NaBr, NaCl,... 

After the critical concentration the conductance of the anion is observed to drop very sharply to zero and to pass into negative values. This is the same type of transport number behaviour as that shown by cadmium iodide (Chapter 2) and indicates that the anions are preferentially transported to the cathode rather than to the anode. It is evident that ion association between anions and positively charged micelles is the cause. Hartley calculated that in cetylpyridinium bromide about 53 bromide ions are associated with each micelle of 68 cationic species to give a net charge of +15. 

Hexadecylpyridinium chloride, cetylpyridinium chloride n-Hexadecyltrimethylammonium bromide (hydroxide) or cetyltrimethylammonium bromide (hydroxide) Stoichiometric concentration of surfactant (detergent) Concentration of micellized surfactant generally [D ] = [D]-cwc... 

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