A simple, accurate, sensitive and rapid method for the determination of some aromatic amines in either the pure form or in pharmaceutical formulation or in biological fluids or in waste water sample is proposed. The method is based on the formation of colored compounds with sodium 1,2-naphthoquinone-4-sulphonate and cetyltrimethyl ammonium bromide in alkaline medium. Beer’s law of colored speci...

Cetyltrimethyl ammonium bromide cationic (CTAB) surfactant was used as template for the synthesis of nanoclusters of ZnS composed of nanowires, by hydrothermal method. The structural and morphological studies were performed by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM) techniques. The synthesized ZnS nanocluster...

In the title compound, C(12)H(28)N(+)·Br(-)·H(2)O, the ionic pairs formed by n-dodecyl-ammonium cations and bromide anions are arranged into thick layers; these layers are linked in a nearly perpendicular fashion [the angle between the layers is 85.84 (5)°] by hydrogen-bonding inter-actions involving the water mol-ecules. The methyl-ene part of the alkyl chain in the cation adopts an all-trans ...

The title compound {systematic name: 1-(2-bromo-benz-yl)-5-ethenyl-2-[hy-droxy(quinolin-4-yl)meth-yl]-1-aza-bicyclo-[2.2.2]octan-1-ium bromide}, C(26)H(28)BrN(2)O(+)·Br(-), is a chiral quater-nary ammonium salt of one of the Cinchona alkaloids. The planes of the quinoline and of the bromo-benzyl substituent are inclined to one another by 9.11 (9)°. A weak intra-molecular C-H⋯O hydrogen bond occ...

The interaction of pyridine-4(-3,-2)aldoxime has been studied whit 3-bromo-N,N,N-trialkyl-2oxo(-hydroxyimino)-1-propanaminium bromide. The structure of all synthesized compounds was determined by elemental analysis as well as by physical and chemical methods. All synthesized compounds were tested for reactivation of phosphorylated acetylcholinesterase. Using fragments of the molecules (an oxime...

Surfactants such as didodecyldimethyl ammonium bromide (DDAB) and 1,2-dilauroyl-sn-phosphatidylcholine (DLPC) form bilayers at the walls of bare silica capillaries. Once formed, these bilayers are stable in the absence of surfactant in the buffer. DDAB provides a cationic bilayer coating which yields a strong reversed EOF and is effective for separation of cationic proteins. DLPC provides a zwi...

The functional silica/polyamide-imide composite films were prepared via simple ultrasonic blending, after the silica nanoparticles were modified by cationic surfactant-cetyltrimethyl ammonium bromide (CTAB). The composite films were characterized by scanning electron microscope (SEM), thermo gravimetric analysis (TGA) and thermomechanical analysis (TMA). CTAB-modified silica nanoparticles were ...

Sodium dodecyl sulfate (SDS) self assembles at hydrophobic graphite surfaces forming linear parallel hemicylinders with approximately 5 nm spacing between adjacent hemicylinders. In this paper, we report the effect of cosurfactants on the SDS surface micelle structures. It is known from the literature that cosurfactants influence the relaxation times of bulk phase micelles. Specifically, the re...

New quaternary 3-phthalimidopropylammonium conjugates of steroids were obtained by reaction of sterols (ergosterol, cholesterol, cholestanol) and bile acids (lithocholic, deoxycholic, cholic) with bromoacetic acid bromide to give sterol 3β-bromoacetates and bile acid 3α-bromoacetates, respectively. These intermediates were subjected to nuclephilic substitution with N,N-dimethyl-3-phthalimidopro...

Pulsed Field Gradient NMR experiments, in their original time domain, have been carried out to separate both water and surfactant self-diffusion coefficients in the micel[ar solution of the system cety[trimethy[ammonium bromide/water. These results have been supported by those obtained by NMR experiments performed with a Fourier Transform spectrometer. The water selfdiffusion coefficients were ...