A quantitative HPLC – fluorescence method for the simultaneous determination of sulfamerazine (SMR) and sulfamethoxazole (SMX) in honey has been developed. Sample pretreatment included acidic hydrolysis, followed by solid phase extraction (SPE) procedure. The liquid chromatography (LC) separation was carried out on RP C 18 column and sulfonamides were detected by fluorescence detector after pre...

The crystals in animal biominerals, such as sea urchin spines, mollusk shells, and coral skeletons, form by attachment of amorphous particles that subsequently crystallize. Do these solid precursor have liquid precursors? Polymer-induced precursors (PILP) or prenucleation clusters coalescing into a to calcium carbonate crystallization been observed extensively synthetic systems. Molecular dynam...

of amino alcohols using Z-L-Glu-L-Pro or Z-L-Glu-D-Pro as chiral counter ions and Hypercarb as the solid phase. Chirality 9: 650}655. Knox JH and Jurand J (1982) Separation of optical isomers by zwitterion pair chromatography. Journal of Chromatography 234: 222}224. Knox JH and Ross P (1997) Carbon-based packing materials for liquid chromatography. Advances in Chromatography, 74}162. Petterson ...

The functional mechanisms of local anesthetics (LAs) have not yet been fully explained, despite their importance in modern medicine. Recently, an indirect interaction between channel proteins and LAs was proposed as follows: LAs alter the physical properties of lipid membranes, thus affecting the channel proteins. To examine this hypothesis, we investigated changes in thermal stability in lipid...

We describe a fluoroimmunoassay for progesterone in serum or plasma. The assay involves use of an antiserum to progesterone-11-hemisuccinate and a labeled antigen prepared by linking fluoresceinamine to progesterone-3-carboxymethyloxime by use of a mixed-anhydride procedure. Serum or plasma samples are extracted with hexane. After incubation of a portion of the evaporated extract with antiserum...

Comparative Study of Liquid-Liquid Extraction and Solid-Phase Extraction Methods for the Separation of Sufentanil from Plasma before Gas Chromatographic– Mass Spectrometric Analysis, Christelle Dufresne, Patrick Favetta, Chantal Paradis, and Roselyne Boulieu ( Université Claude Bernard Lyon 1 (U.C.B.L.), Institut des Sciences Pharmaceutiques et Biologiques (I.S.P.B.), Département de Pharmacie C...

Individual tocopherol profile of five Agaricus mushroom species, widely consumed in Portugal, was obtained by a normal-phase high-performance liquid chromatography (NP-HPLC). It was used a simple solid-liquid extraction procedure without saponification step and the chromatographic separation was achieved using a YMC-Pack Polyamine II column using an isocratic elution with hexane/ethyl acetate (...

A convenient solid phase method for extracting and fractionating steroid hormones from serum or urine is presented. The influence of the solvent used for extraction, of the body fluid to be extracted, and of the degree of sample dilution on the efficiency of extraction was studied for progesterone and cortisol. The potency of fractionation was demonstrated by the separation of the steroid pairs...

Various biological and chemical processes lead to the nucleation growth of non-wetting fluid bubbles within pore space a granular medium, such as formation gas in liquid-saturated lake-bed sediments. In sufficiently soft porous materials, nature these can result open cavities solid skeleton. Here, we consider this process through lens phase separation, where thermomechanics govern separation fr...