Thin-layer chromatography fluorescence spectroscopy

Finally, and apart from the importance of micelles in the solubilization of chemical species, mention should also be made of their intervention in the displacement of equilibria and in the modification of kinetics of reactions, as well as in the alteration of physicochemical parameters of certain ions and molecules that affect electrochemical measurements, processes of visible-ultraviolet radiation, fluorescence and phosphorescence emission, flame emission, and plasma spectroscopy, or in processes of extraction, thin-layer chromatography, or high-performance liquid chromatography [2-4, 29-33],... 

Dunn and Stich [78] and Dunn [79] have described a monitoring procedure for polyaromatic hydrocarbons, particularly benzo[a]pyrene in marine sediments. The procedures involve extraction and purification of hydrocarbon fractions from the sediments and determination of compounds by thin layer chromatography and fluorometry, or gas chromatography. In this procedure, the sediment was refluxed with ethanolic potassium hydroxide, then filtered and the filtrate extracted with isooctane. The isooctane extract was cleaned up on a florisil column, then the polyaromatic hydrocarbons were extracted from the isoactive extract with pure dimethyl sulphoxide. The latter phase was contacted with water, then extracted with isooctane to recover polyaromatic hydrocarbons. The overall recovery of polyaromatic hydrocarbons in this extract by fluorescence spectroscopy was 50-70%. 

C. G. A. Bos and J. G. J. Frijns, Quantitative analysis of dihy-droergotamine in pharmaceuticals using fluorescent spectroscopy and thin-layer chromatography, Pharm. Weekbl., 107 111 (1972). 

The sorption efficiency of MC was determined as the ratio of the quantity of the adsorbed substance to its initial amount (w / w), expressed in % for a certain ratio (w / w) of adsorbent to substance. Optimal ratios of adsorbent to substance equal 15-20 for barbiturates, 20 - 25 for cyanocobalamin and bilirubin, and 40 - 50 for hemoglobin. The initial concentration of absorbed substances was 100 - 200 pg/ml. The substances were incubated for lmin with MC either in physiological solution or in donor plasma and donor blood at room temperature (pH 7.4). The concentration of substances in the solutions was measured by differential visual and UV-spectroscopy. Concentrations of substances in blood and plasma and adsorption of total plasma proteins was determined by thin-layer chromatography with a fluorescent label. 

Technical examination of objects coated with a protective covering derived from the sap of a shrubby tree produces information that can be used to determine the materials and methods of manufacture. This information sometimes indicates when and where the piece was made. This chapter is intended to present a brief review of the raw material urushi, and the history and study of its use. Analytical techniques have included atomic absorption spectroscopy, thin layer chromatography, differential thermal analysis, emission spectroscopy, x-ray radiography, and optical and scanning electron microscopy these methods and results are reviewed. In addition, new methods are reported, including the use of energy dispensive x-ray fluorescence, scanning photoacoustical microscopy, laser microprobe and nondestructive IR spectrophotometry. 

High Performance Liquid Chromatography Electrophoresis Thin Layer Chromatography Ultraviolet and Visible Spectroscopy Fluorescence and Phosphorescence Atomic Absorption and Plasma Spectroscopy X-ray Methods Mass Spectrometry... 

Another important application of CDs is (chiral) drug analysis. In this field, CDs are used in combination with UV-VIS spectrometry, fluorescence and NMR spectroscopy, mass spectrometry, in electrochemical analysis and most widely in various separation techniques such as thin-layer chromatography (TLC), gas chromatograpy (GC), high-performance liquid chromatography (HPLC), super- and subcritical fluid chromatography (SFC) [13] and capillary electrophoresis (CE) [9], [16]. 

Fluorescamine is employed for more sensitive determination of amino acids by fluorescence spectroscopy. Since it undergoes rapid hydrolysis under aqueous conditions, the reagent is normally dissolved in acetone. It is commonly employed for the detection of amino acids on surfaces, such as thin-layer chromatography (TLC) plates. Amino acids are detected based on emission of light at 470 nm following excitation at 390 nm. Detection limits for amino acids are in the low picomole range. 

See also Asbestos. Color Measurement. Forensic Sciences Thin-Layer Chromatography. Gas Chromatography Pyrolysis Mass Spectrometry Fourier Transform Infrared Spectroscopy. Microscopy Applications Forensic. Spectrophotometry Diode Array. Textiles Natural Synthetic. X-Ray Absorption and Diffraction X-Ray Diffraction - Powder. X-Ray Fluorescence and Emission X-Ray Fluorescence Theory Energy Dispersive X-Ray Fluorescence Total Reflection X-Ray Fluorescence. 

Dytkiewitz, E. and Morlock, G.E. 2008, Analytical strategy for rapid identification and quantification of lubricant additives in mineral oil by high-performance thin-layer chromatography with UV absorption and fluorescence detection combined with mass spectrometry and infrared spectroscopy, J. AOAC Int., 91 1237-1243. 

HPLC High liquid chromatography, ED electrochemical detector, ESI electrospray ionization, MS tandem mass spectrometry, LPT Liquid-phase sorbent trapping, TD Thermal desorption, GC Gas chromatography, TLC Thin layer chromatography, DAD Diode Array, FD Fluorescence detection, FTIR Fourier transform infrared spectroscopy, SPME Solid phase microextraction... 

The chimney-sweeper cancer described by P. Pott in England as early as 1775, which is basically related to soot but not to carbon black, was the starting point of intensive research on analytical test methods for polycyclic aromatic hydrocarbons (PAH) in carbon blacks. Increasingly refined test methods have been developed (e.g., column, thin-layer, and paper chromatography, gas chromatography, UV and fluorescence spectrophotometry, and mass spectroscopy) to detect traces of such substances and to investigate the ability of carbon black surfaces to adsorb and to desorb PAHs. 

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