RESUMO
The polar metabolites of polycyclic aromatic compounds (PACs) are of significant oncological interest. In contrast to parent PACs, isomer selective detection of polar PACs by laser excited Shpol'skii spectrometry (LESS) is severely limited by excessively broadened spectra and rapid photodegradation in n-alkane solvents. To minimize these limitations a 10-min derivatization procedure was developed to produce corresponding methoxy compounds, that exhibit the Shpol'skii effect. By use of the extraction and permethylation procedure, the selective detection of a mixture of hydroxy-benz[a]anthracene isomers spiked at the low picogram level into urine and blood matrices was achieved. A detection limit for 1-hydroxybenz[a]anthracene was 0.6 part per trillion, or 12 fg (0.05 fmol) on a 20-microL sample.
Assuntos
Benzo(a)Antracenos/análise , Lasers , Espectrometria de Fluorescência , Benzo(a)Antracenos/metabolismo , Líquidos Corporais/análise , Fenômenos Químicos , QuímicaRESUMO
Methods are presented for the determination of methylmercury in fish, water, urine, and sediments, and diorganomercury compounds in water. Two significant differences from previous methods are the use of methylene chloride extracting solvent which permits sample extracts to be concentrated to volumes as low as 0.1 mL, and use of a gas chromatograph interfaced to an atmospheric pressure active nitrogen (APAN) afterflow detector. Such a detector is very sensitive and selective for Hg at picogram levels. Thus, limits of detection were significantly enhanced.
