Spectral studies on the interaction of capsular polysaccharide (SPS) isolated from Klebsiella serotype K34, with oppositely charged dyes and surfactants have been reported. The SPS was acidic in nature and induced strong metachromacy (~110 nm blue shift) in the cationic dye pinacyanol chloride (PCYN) which was due to “card-pack stacking” of individual dye monomers on the surface of the polyanio...

The proposed work describes the nanodrop spectrophotometric determination of cationic surfactants using citrate-modified silver nanoparticles based on the aggregation of silver nanoparticles induced by cationic surfactants due to the hydrophobic effect. The visible color change in the solution of silver nanoparticle includes a red shift with the quenching of the absorption spectra. The maximum ...

The nature and strength of the interactions between a cationic fluorophore, Rhodamine 123 (R123), and surfactants of different head charge are investigated. Series of absorption and fluorescence emission spectra and of fluorescence decays are measured. R123 does not interact with the monomers of both nonionic and cationic surfactants but it presents affinity to their micelles. A partition equil...

hydroxyapatite (ha) nano-rods with uniform morphology and controllable size have been successfully synthesized in the presence of cationic and non-ionic surfactants by a hydrothermal method. (nh4) 2hpo4 and ca(no 3)2.4h2o were used as the phosphorus and calcium sources, respectively. the composition of synthesized powders was characterized using x-ray diffraction, and fourier transform infrared...

This report compares the effect of lipid and polymeric nanoparticles upon human neutrophils in the presence of cationic surfactants. Nanostructured lipid carriers and poly(lactic-co-glycolic) acid nanoparticles were manufactured as lipid and polymeric systems, respectively. Some cytotoxic and proinflammatory mediators such as lactate dehydrogenase (LDH), elastase, O2(•-), and intracellular Ca(2...

Surfactants have the special ability to interact with the lipid bilayer of cell membranes. The red blood cell is one of the most used cellular membrane models to study the mechanisms underlying surfactant – induced osmotic cell resistance.The aim of this study is the evaluation of the effect of the prepared surfactants on red blood cells (RBC) as a model for biological membranes. Also, in this ...

In this paper, we report studies which aim to elucidate the mechanisms involved in the antimicrobial activity of three cationic lysine-based surfactants: LLM, LALM, and C6 (LL)2. To this end, a simple membrane model (i.e., 1,2-dipalmitoyl-sn-phosphatidylcholine, DPPC) was used to explore the monolayer properties at the air/liquid interface. Compression π-A isotherms of mixtures of DPPC/lysine s...

We examined the enhancement effects of the double-chained cationic surfactants of n-dimethyldialkylammoniums (CH(3))(2)N(+)(C(n)H(2n+1))(2) on the permeation of anionic salicylate through excised guinea pig dorsal skin at pH 7.4. Among them, n-dimethyldidecylammonium (2C10), which seemed to form micelles, had dose-dependent enhancement effects at concentrations of more than 0.1 mM, and about a ...

We study the influence of different surfactants on NaCl crystallization during evaporation of aqueous salt solutions. We found that at concentrations of sodium chloride close to saturation, only the cationic surfactant CTAB and the nonionic surfactant Tween 80 remain stable. For the nonionic surfactant, the high concentration of salt does not significantly change either the critical micellar co...

A cationic surfactant-selective electrode for sensitive analysis of cationic surfactant has been developed by using a plasticized poly (vinyl chloride) membrane based on nanocomposite cation exchanger polypyrrole zirconium titanium phosphate. The electrode is excellently selective for the cetyl trimethyl ammonium bromide (CTAB) ion over inorganic ions and other cationic surfactants. The membran...