Particles of titanium dioxide (TiO2) are widely used as white pigments in paints and inks, due to their brightness and high refractive index. Yet, with TiO2 having a high density (4.2 g/cm), particles with typical sizes of 300 nm sediment rapidly even before significant agglomeration can occur. Thus, increasing the stability of TiO2 dispersions against sedimentation as well as aggregation is im...

In the synthesis of nanoparticles, phenomenon agglomeration is an undesirable condition because particles formed can be larger. The use surfactants prevent occurrence this phenomenon. study, was studied in nanosilica from geothermal sludge. method applied sol-gel method. A 1 M sodium hydroxide (NaOH) solution used to prepare sol phase, while gel phase prepared at pH 5 using a 1.5 hydrochloric a...

A new serotype of Staphylococcus hyicus exfoliative toxin (SHET), serotype B, was isolated from the culture filtrate of a plasmid-carrying strain of S. hyicus. The new SHET was purified by precipitation with 70% saturated ammonium sulfate, gel filtration on a Sephadex G-75 column, column chromatography on DEAE-Cellulofine A-500, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS...

Recent reports show that contrary to common perception, branched alkyl sulfate surfactants are readily biodegradable in standard biodegradability tests. We report here the isolation of bacteria capable of biodegrading 2-butyloctyl sulfate and the identification of novel enzymes that initiate the process. Enrichment culturing from activated sewage sludge yielded several strains capable of growth...

Thermophilic Bacillus sp. GUS1, isolated from  a soil  sample obtained from citrus garden, produced at least three proteases as detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and zymogram analysis. The enzymes were stable in the alkaline pH range (8.0-12.0), with the optimum temperature and pH range of the proteases being 70ºC and 6.0-12.0, respectively. All th...

The use of aqueous mixed micellar system consisting of sodium dodecyl sulfate (SDS) and polyoxyethylene (23) dodecanol (Brij-35) as the mobile phase in reversed-phase liquid chromatography was studied. A group of chlorophenols was used as the test mixture. Adding organic modifier to the system showed that the use of low concentrations of organic additives improves efficiency in SDS/Brij-35 mixe...

Various concentrations of anionic surfactant, sodium dodecyl sulfate (SDS), were used to control the growth of calcium carbonate crystals. The obtained calcium carbonate particles were characterized by Fourier transform infrared spectrometry (FT-IR), X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), laser scattering particle size analyzer and zeta potential analyzer...

Many properties of chemicals depend on their streochemistry. Among these, the effects of streoisomerism on percutaneous absorption of drugs, which is subject of the present investigation, is not well studied yet. In this study, tretinoin (TT) and isotretinoin (ITT) (geometric isomers) were chosen and their permeations (alone or in the presence of each other) through enhancer-treated excised ...

We performed atomistic molecular dynamics simulations of anionic and cationic micelles in the presence of poly(ethylene oxide) (PEO) to understand why nonionic water-soluble polymers such as PEO interact strongly with anionic micelles but only weakly with cationic micelles. Our micelles include sodium n-dodecyl sulfate (SDS), n-dodecyl trimethylammonium chloride (DTAC), n-dodecyl ammonium chlor...