Solid-phase extraction (SPE) methods are easy, rapid, and reliable. Their growing popularity is in part due to their operational simplicity and cost reduction in solvents, and partly because they are easier to automate. Sphingolipids are implicated in various cellular events such as growth, differentiation, and apoptosis. However, their separation by small SPE cartridges has attracted limited a...

We applied various prepurification protocols (extraction with different solvents, liquid/solid separation on bonded silica media, Celite, and Sephadex LH20 chromatography) with a range of commercially available RIA kits to measure cortisol in urine samples. We then compared the results with the concentrations measured by a HPLC method validated with reference to isotope dilution gas chromatogra...

acetonitrile used as a solvent in manufactures and affects to central nervous system from inhalation exposure. the aim of this study was to develop a micro-solid phase extraction method for  the determination of acetonitrile in the air matrix. the sampling was performed with a small diameter fused silica fiber coated with a thin film of stationary phase and was subsequently desorbed and analyze...

The gas-like mass transfer properties and liquid-like solvation characteristics of supercritical fluid make it a promising medium in performing extractory and chromatographic separations, i.e., supercritical fluid extraction (SFE) and supercritical fluid chromatography (SFC), respectively. The tunable solvation properties of supercritical carbon dioxide not only improve SFE's efficiency and spe...

In the 70s, reports began to appear of phenolic metabolites of brown algae with the characteristics of tannins; these compounds, initially termed phaeophyte tannins, marine algal polyphenols or polyphloroglucinols, are known as phlorotannins, the youngest group of plant polyphenolics. Despite over 40 years of research in phlorotannins, this area is still in the exponential growth phase; however...

separation of ten sedative- hypnotic drugs was performed by rp-hplc using mixed micellar mobile phase. effect of temperature, type and amount of organic modifier in mobile phase on efficiency (n) and asymmetry factor (b/a) showed that, the appropriate conditions for a good separation were 35°c and 7% (v/v) butanol in mobile phase.  variations of selectivity factor versus butanol concentration, ...

Ionic liquids (ILs) have been applied in different areas of separation, such as ionic liquid supported membranes, as mobile phase additives and surface-bonded stationary phases in chromatography separations and as the extraction solvent in sample preparations, because they can be composed from various cations and anions that change the properties and phase behavior of liquids. Although the appl...

Background and objectives: Chromatography fingerprinting is considered as a comprehensive method for quality control, diagnosis and the nature of herbal drugs, and it is important to classify the different samples of medicinal plants and determine the chemical species present in them. Methods: In this research, a new strategy based on the combination of multiva...

1-(2-Pyridylazo)-2-naphthol has been used for extraction concentration of palladium, copper, cobalt and nickel from aqueous solutions and subsequent separation of the chelates obtained, by means of high-pressure liquid chromatography. A technique for determining microamounts of palladium in aqueous solutions in the presence of 100-fold ratio of copper and 80-fold ratio of cobalt has been develo...

A reversed-phase high-performance liquid chromatography method using evaporative light-scattering detection is developed for the determination of residual octylglucoside (OG) levels after a detergent exchange step for in-process samples of a vaccine antigen. The reversed-phase column not only provides separation of the OG but also functions as an extraction column to remove the vaccine antigen ...