Thin-layer chromatography microwave extraction

Basic alumina (18 g) was added to the solution of phenylhydrazine (1.4 g, 0.013 mol) and chalcone 1 (2.38 g, 0.01 mol) dissolved in dichloromethane (5 ml) at room temperature. The reaction mixture was thoroughly mixed and the adsorbed material was dried in air (beaker) and placed in an alumina bath inside a microwave oven. Upon completion of the microwave reaction (1-2 min), based on thin-layer chromatography (TLC) examination, the mixture was cooled to room temperature and then the product was extracted into dichloromethane (4x15 ml). Removal of the solvent under reduced pressure gave the product, which was purified by crystallization from a mixture of methanol and dichloromethane. The yield of 2 was 82%. 

Other techniques that have been used to determine polycyclic aromatic hydrocarbons in soil extracts include ELISA field screening [86], micellar elec-tr okinetic capillary chromatography [ 87], supersonic jet laser-induced fluorescence [88,89], fluorescence quenching [90], thermal desorption gas chromatography-mass spectrometry [81,90,100], microwave-assisted extraction [91], thermal desorption [92], immunochemical methods [93,94], electrophoresis [96], thin layer chromatography [95], and pyrolysis gas chromatography [35]. 

HPLC, coupled with element-specific detectors such as AAS, AFS, ICP-MS and microwave-induced plasma atomic emission spectrometry (MIP-AES). In general, methods for mercury speciation are classified according to the isolation/separation technique and the detection systems (Horvat 1996, Carro and Mejuto 2000). Most methods for isolation/separation are based on solvent extraction, differential reduction, difference calculation between total and ionic mercury, derivatization, or on paper- and thin-layer chromatography. 

Microwave-Assisted Solvent Extraction Pressurized Fluid Extraction Supercritical Fluid Extraction Solid-Phase Extraction Solid-Phase Microextraction. Gas Chromatography Overview, Mass Spectrometry Environmental Applications. Immunoassays Overview. Liquid Chromatography Overview Reversed Phase Size-Exclusion Liquid Chromatography-Mass Spectrometry. Pesticides. Supercritical Fluid Chromatography Overview Applications. Thin-Layer Chromatography Overview. Water Analysis Organic Compounds. 

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