Generalized Analytic Approach for Determination of Multidimensional Franck–Condon Factors: Simulated Photoelectron Spectra of Polynuclear Aromatic Hydrocarbons

Abstract A simple, rapid method has been developed for the separation and determination of polynuclear aromatic hydrocarbons (PAHs) in barley malt. An ultrasonic- cyclohexane extraction method was used to separate the PAHs from ground barley malt. The cyclohexane extracts were purified by chromatography through a water-deactivated silica gel-alumina column. The eluate from the column was concentrated and purified further by partitioning between dimethyl sulfoxide (DMSO) and cyclohexane. The DMSO extract was diluted with water and the PAHs were extracted back into cyclohexane. The cyclohexane extract was washed with water, dried through sodium sulfate, and evaporated, and the resulting residue was dissolved in 80% aqueous acetonitrile-methanol (1 + 1) and subjected to reverse phase high performance liquid chromatography. Thirty barley malt samples were analyzed using this procedure. Peaks having the same retention time as the carcinogen benzo(a)pyrene were isolated from 18 of the samples, and were equivalent to trace levels ranging from <0.1 to 0.2 ppb. Average recoveries of 11 PAHs, including benzo(a)pyrene, benzo(b)fluoranthene, indeno(l,2,3-cd)pyrene, and benz(a)anthracene, added to 25 g samples at 2.5 and 5 ppb, ranged from 78 to 97%, with a mean relative standard deviation of 6.6%.

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Improved Method for Determination of Polynuclear Aromatic Hydrocarbons in Pharmacopoeial Paraffin and Mineral Oils

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/74.6.968 ◽

1991 ◽

Vol 74 (6) ◽

pp. 968-973

Author(s):

Aziz Geahchan ◽

I Le Gren ◽

Paul Chambon ◽

Renee Chambon

Keyword(s):

Gas Chromatography ◽

Liquid Chromatography ◽

Quantitative Determination ◽

Aromatic Hydrocarbons ◽

Detectable Level ◽

Polynuclear Aromatic Hydrocarbons ◽

Improved Method ◽

Fluorometric Determination ◽

Mineral Oils

Abstract An improved method has been developed for quantitative determination of poiynuciear aromatic hydrocarbons (PAHs) in pharmacopoeial paraffin and medicinal white oil samples. This new method combines 2 liquid-liquid partition and adsorption chromatography procedures with a 2-step purification on Sephadex LH 20 and liquid chromatography with fluorometric determination. Selective elution of PAHs results in absence of background fluorescence. The minimum detectable level ranges from 0.2 ppt for benzofluoranthene isomers to 200 ppt for acenaphthene. Recoveries of PAHs added at 7 ppm varied from 92.1 to 111.4%. When a variety of medicinal white oil samples were analyzed by this improved method, 27 PAHs were identified, including 11 suspected carcinogens. Their identities were confirmed by capillary gas chromatography.

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Determination of Polynuclear Aromatic Hydrocarbons in Seafood by Liquid Chromatography with Fluorescence Detection

Journal of AOAC International ◽

10.1093/jaoac/75.5.872 ◽

1992 ◽

Vol 75 (5) ◽

pp. 872-877 ◽

Cited By ~ 5

Author(s):

Gracia A Perfetti ◽

Patricia J Nyman ◽

Sheryl Fisher ◽

Frank L Joe ◽

Gregory W Diachenko

Keyword(s):

Liquid Chromatography ◽

Fluorescence Detection ◽

Aromatic Hydrocarbons ◽

Solid Phase ◽

Reversed Phase ◽

Polynuclear Aromatic Hydrocarbons ◽

Matrix Interferences ◽

Phase Liquid ◽

Certified Values

Abstract Modification of a previously published method for determination of polynuclear aromatic hydrocarbons (PAHs) produces very clean seafood extracts in less than half the time. After alkaline digestion of the seafood, PAHs were partitioned into 1,1,2- trichlorotrifluoroethane. The resulting extract was cleaned up by solid-phase extraction on alumina, silica, and C18 adsorbents and then analyzed by gradient reversed-phase liquid chromatography with programmable fluorescence detection. Average recoveries of 12 PAHs [acenaphthene, anthracene, fluoranthene, pyrene, benz(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)- fluoranthene, benzo(a)pyrene, dibenz(a,h)anthracene, benzo(ghi)perylene, and indeno(1,2,3-cd)pyrene] from 5 different matrixes (mussels, oysters, clams, crabmeat, and salmon) spiked at low partsper- billion levels ranged from 76 to 94%. Estimated limits of quantitation ranged from 0.01 to 0.6 ppb PAHs in extracts that were free of matrix interferences. Results of analyses of a mussels standard reference material obtained from the National Institute of Standards and Technology were in good agreement with the certified values.

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