sodium-dodecyl-sulfate and dodecylamine

Topics: Amines; Electrochemical Techniques; Oxides; Rheology; Sodium Dodecyl Sulfate; Surface-Active Agents; Suspensions; Tungsten

The viability of A549 cells, a human lung carcinoma epithelial cell line, was evaluated after exposure to graphene oxide (GO) and its derivatives (dodecylamine GO (DA-GO), reduced GO (rGO), and sodium dodecyl sulfate rGO (SDS-rGO)). A decrease in the relative amounts of C-OH bonds and an increase in the number of C-C and C-N bonds in the C 1s spectra indicated that the reduction of GO to rGO and the surface functionalization of GO has taken place. The appearance of amine stretching bands, out-of-plane C-H stretching vibrations, and S = O stretching bands in the infrared spectra indicated the formation of DA-GO, rGO, and SDS-rGO, respectively. Low concentrations (3-25 µg/mL) of GO, rGO, and SDS-rGO were found to be mildly toxic, whereas DA-GO exhibited severe dose-dependent toxicity over the same concentration range. High concen- trations (50-400 µg/mL) of GO and all its derivatives resulted in severe toxicity to the A549 cells. It is believed that surface functionality strongly affects the viability of A549 cells.

Topics: Amines; Cell Line, Tumor; Cell Survival; Epithelial Cells; Graphite; Humans; Lung; Models, Molecular; Molecular Conformation; Oxidation-Reduction; Oxides; Sodium Dodecyl Sulfate; Surface Properties

Functionalized ionic liquids containing the tris(pentafluoroethyl)trifluorophosphate (FAP) anion were used as extraction solvents in dispersive liquid-liquid microextraction (DLLME) for the extraction of 14 emerging contaminants from water samples. The extraction efficiencies and selectivities were compared to those of an in situ IL DLLME method which uses an in situ metathesis reaction to exchange 1-butyl-3-methylimidazolium chloride (BMIM-Cl) to 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide (BMIM-NTf(2)). Compounds containing tertiary amine functionality were extracted with high selectivity and sensitivity by the 1-(6-amino-hexyl)-1-methylpyrrolidinium tris(pentafluoroethyl)trifluorophosphate (HNH(2)MPL-FAP) IL compared to other FAP-based ILs and the BMIM-NTf(2) IL. On the other hand, polar or acidic compounds without amine groups exhibited higher enrichment factors using the BMIM-NTf(2) IL. The detection limits for the studied analytes varied from 0.1 to 55.1 μg/L using the traditional IL DLLME method with the HNH(2)MPL-FAP IL as extraction solvent, and from 0.1 to 55.8 μg/L using in situ IL DLLME method with BMIM-Cl+LiNTf(2) as extraction solvent. A 93-fold decrease in the detection limit of caffeine was observed when using the HNH(2)MPL-FAP IL compared to that obtained using in situ IL DLLME method. Real water samples including tap water and creek water were analyzed with both IL DLLME methods and yielded recoveries ranging from 91% to 110%.

Topics: Amines; Chemical Fractionation; Chromatography, High Pressure Liquid; Hydrocarbons, Fluorinated; Hydrogen-Ion Concentration; Imidazoles; Ionic Liquids; Pharmaceutical Preparations; Rivers; Sensitivity and Specificity; Sodium Chloride; Sodium Dodecyl Sulfate; Water Pollutants, Chemical

Alloyed gold/silver nanoparticles with a core/shell structure are produced from preformed gold and silver nanoparticles during ultrasonic treatment at different intensities in water and in the presence of surface-active species. Preformed gold nanoparticles with an average diameter of 15 + or - 5 nm are prepared by the citrate reduction of chloroauric acid in water, and silver nanoparticles (38 + or - 7 nm) are formed after reduction of silver nitrate by sodium borohydride. Bare binary gold/silver nanoparticles with a core/shell structure are formed in aqueous solution after 1 h of sonication at high ultrasonic intensity. Cationic-surfactant-coated preformed gold and silver nanoparticles become gold/silver-alloy nanoparticles after 3 h of sonication in water at 55 W cm(-2), whereas only fusion of isolated gold and silver nanoparticles is observed after ultrasonic treatment in the presence of an anionic surfactant. As the X-ray diffraction profile of alloyed gold/silver nanoparticles reveals split, shifted, and disappeared peaks, the face-centered-cubic crystalline structure of the binary nanoparticles is defect-enriched by temperatures that can be as high as several thousand Kelvin inside the cavitation bubbles during ultrasonic treatment.

Topics: Adsorption; Alloys; Amines; Colloids; Gold; Metal Nanoparticles; Silver; Sodium Dodecyl Sulfate; Sonication; Spectrophotometry, Ultraviolet; Ultrasonics; Water; X-Ray Diffraction

Adsorption of collectors and modifying reagents in the flotation of oxide and silicate minerals is controlled by the electrical double layer at the mineral-water interface. In systems where the collector is physically adsorbed, flotation with anionic or cationic collectors depends on the mineral surface being charged oppositely. Adjusting the pH of the system can enhance or prevent the flotation of a mineral. Thus, the point of zero charge (PZC) of the mineral is the most important property of a mineral in such systems. The length of the hydrocarbon chain of the collector is important because of chain-chain association enhances the adsorption once the surfactant ions aggregate to form hemimicelles at the surface. Strongly chemisorbing collectors are able to induce flotation even when collector and the mineral surface are charged similarly, but raising the pH sufficiently above the PZC can repel chemisorbing collectors from the mineral surface. Zeta potentials can be used to delineate interfacial phenomena in these various systems.

Topics: Adsorption; Amines; Colloids; Electrolytes; Hydrocarbons; Hydrogen-Ion Concentration; Ions; Kinetics; Micelles; Oxides; Salts; Silicates; Sodium Dodecyl Sulfate; Surface Properties; Surface-Active Agents; Thermodynamics

Topics: Amines; Dental Enamel; Detergents; Fluorides; Humans; Lipids; Organic Chemicals; Quaternary Ammonium Compounds; Sodium Dodecyl Sulfate; Surface-Active Agents