University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Hydrocarbons, aromatic, polycyclic

@ ChemSpider@ NIST@ PubChem

Citations 8

"Liquid Chromatographic Method With Fluorescence Detection For The Determination Of Polycyclic Aromatic Hydrocarbons In Environmental Samples"
Anal. Chim. Acta 1990 Volume 234, Issue 1 Pages 269-273
M. D. Núñez and F. Centrich

Abstract: A method for the determination of some polynuclear aromatic hydrocarbons (PAHs) in water samples and air filters is presented. Samples were extracted with light petroleum-diethyl ether (85 + 15) and the extracts were concentrated before analysis. Reversed-phase liquid chromatography with fluorescence detection was applied to separate and determine the PAHs. Recoveries of individual PAHs from spiked water samples were 0.16-0.27 ng mL-1. Detection limits in the picogram range were obtained for each compound.
Environmental LC Fluorescence Sample preparation Filter Extraction Post-column derivatization

"Multiple Solvent Extraction System With Flow Injection Technology"
Anal. Chem. 1982 Volume 54, Issue 1 Pages 87-91
Dennis C. Shelly, Thomas M. Rossi, and Isiah M. Warner

Abstract: A three-stage extraction procedure for the isolation of polycyclic aromatic compounds from complicated sample matrices has been automated by use of flow injection technology. Three single-step liquid-liquid extractions are linked together by multichannel pumping and resampling. In addition to the multiple extraction capability, the system demonstrates two other novel features. First, both Teflon and glass extraction coils are used to minimize sample carryover and memory effects. Second, microprocessor-controlled pneumatically actuated valves control sample injection and effluent concentration. The performance of the system is evaluated by high-performance liquid chromatography and video fluorometric analyzes of both automated and manually performed extractions of a crude oil-ash residue sample. The three extraction system is rapid, reproducible, and quantitative as compared to an identical manual procedure.
Sample preparation Solvent extraction

"Optimization Of A Flow Injection Analysis System For Multiple Solvent Extraction"
Anal. Chem. 1982 Volume 54, Issue 12 Pages 2056-2061
Thomas M. Rossi, Dennis C. Shelly, and Isiah M. Warner

Abstract: The performance of a multistage flow injection analysis solvent extraction system has been optimized. The effect of solvent segmentation devices, extraction coils, and phase separators on performance characteristics is discussed. Theoretical consideration is given to the effects and determination of dispersion and the extraction dynamics within both glass and Teflon extraction coils. The optimized system has a sample recovery similar to an identical manual procedure and a 1.5% relative standard deviation between injections. Sample throughput time is under 5 min. These characteristics represent significant Improvements over the performance of the same system before optimization.
Sample preparation Optimization Review Phase separator Solvent extraction

"Determination Of Polycyclic Aromatic Hydrocarbons In Diesel Soot By High Performance Liquid Chromatography"
Fresenius J. Anal. Chem. 1991 Volume 340, Issue 1 Pages 27-30
H.-J. Götze Contact Information, J. Schneider and H.-G. Herzog

Abstract: Soot particles from exhaust fumes are collected by blowing exhaust gases for 2 min through an Al collection apparatus containing a borosilicate - glass-fiber extraction thimble. The sample is extracted with CHCl2 for 2 h in a Soxtec extractor, the extract is cleaned up on a SiO2 column (20 cm x 11 mm), eluted with CHCl2 and the eluate was treated with Al2O3 and evaporated to dryness. The residue is placed on top of an alumina column and PAHs are separated by elution with benzene, CHCl3 - 1% ethanol and methanol. These fractions were further analyzed by reversed-phase HPLC on a column (25 cm x 1 mm) of Nucleosil RP 18 (5 µm) with a mobile phase (30 µL min-1) of methanol - THF - water (49:21:30) and detection at 254 nm for the benzene fraction and fluorescence detection at 370 nm (excitation at 289 nm) for the CHCl3 fraction after post-column derivatization. The calibration graph was rectilinear over three orders of magnitude and the detection limit was 0.05 pg to 0.3 ng.
Diesel Soot HPLC Fluorescence Sample preparation Column Extraction Post-column derivatization

"Simultaneous Identification Of Different Classes Of Hydrocarbons And Determination Of Nitro-polycyclic Aromatic Hydrocarbons By Means Of Particle-beam Liquid Chromatography-mass Spectrometry"
J. Chromatogr. A 1996 Volume 728, Issue 1 Pages 359-369
L. Bonfanti, M. Careri*, A. Mangia, P. Manini and M. Maspero

Abstract: Aliphatic hydrocarbons (C7 to C36), PAH and nitro-PAH were analyzed using a HP 1050 instrument coupled to a Model 5989 A quadrupole MS via a particle beam interface. Samples were applied to a 10 µm LiChrosorb Si-60 column (25 cm x 4.6 mm i.d.). Isocratic elution with heptane was carried out for 5 min followed by a linear gradient of 0-50% THF in heptane over 30 min with a final hold for 5 min. He was the nebulizing gas at 241 kPa and 70°C. For nitro-PAH the best results were obtained by negative-ion CI detection with CH4 as reagent gas. In flow injection experiments maximum ion intensities were obtained in THF/heptane (3:7); detection limits were 1-700 pg nitro-PAH. Calibration graphs were linear over two orders of magnitude.
LC Mass spectrometry

"Separation And Determination Of Trace Dinitropyrenes By Means Of Off-line Reduction-HPLC-chemiluminescence Detection. Application To Assessing Atmospheric Environment"
Anal. Sci. 1994 Volume 10, Issue 4 Pages 583-587
M. MAEDA, K. TSUKAGOSHI, M. MURATA, M. TAKAGI and T. YAMASHITA

Abstract: A FIA system using a bis(2,4,6-trichlorophenyl)oxalate (TCPO)-H2O2 chemiluminescence (CL) system was developed for the determination of trace PAH (details and schematic diagram given). Results obtained allowed the development of a HPLC-CL detection system. Suspended particulate matter in air was collected on a glass-fiber filter and the filter was extracted with CH2Cl2 for 15 min with sonication. The supernatant was filtered, the filtrate was evaporated to dryness under N2, the residue was dissolved in hexane and applied to a Sep-Pak silica cartridge. The cartridge was eluted (details given) and the fraction containing dinitropyrenes (DNP) was concentrated by rotary evaporation, dried under N2 and the residue dissolved in ethanol and mixed with 7% sodium hydrogen sulfide. After 24 h, benzene and 0.15 M NaOH were added with shaking for 15 min. The organic phase was analyzed by HPLC on an ODS column (25 cm x 4.6 mm i.d.) with acetonitrile/10 mM imidazole of pH 7.5 (1:1) as mobile phase and CL detection as above. A metal-free system was developed using a plastic-frame column and PTFE line. The detection limit was 0.025 pg for 1,8- and 1,6-DNP and 0.05 pg for 1,3-DNP.
Particulates HPLC Chemiluminescence

"Determination Of Trace PAHs In Water Samples By Synchronous Fluorophotometry With Flow Injection And Column Preconcentration"
Fenxi Ceshi Xuebao 1998 Volume 17, Issue 2 Pages 68-70
Lin Yuhui, Zhang Yong, Yuan Dongxing

Abstract: A simple and rapid synchronous fluorophotometric method couples with flow injection and column pre-concentration is described for the online simultaneous determination of trace benzo[a]pyrene (BaP) and perylene (Per) in tap and well water. The detection limits of BaP and Per are 0.2 µg.L-1 and 0.04 µg.L-1, respectively. The relative standard deviations are 7.10% and 7.54%, respectively. The recoveries are 93.3-103.3% and 103.3-116.7%, respectively.
Well Water Fluorescence Column Preconcentration

"Rapid PAH Determination In Urban Particulate Air Samples By HPLC With Fluorimetric Detection And Programmed Excitation And Emission Wavelength Pairs"
J. Chromatogr. Sci. 1995 Volume 33, Issue 4 Pages 181-185
M.N. Kayali, S. Rubio-Barroso, and L.M. Polo-Diez

Abstract: The air sample was collected with use of a high-volume MCV sampler and glass fiber Whatman GF/A filters (Clifton, NJ) at a flow rate of 30 m3/h for 24 h. The filters were sonicated with 50 mL CH2Cl2 for 20 min and centrifuged at 4000 rpm. The extraction was repeated with 50 mL CH2Cl2 and the combined extract was evaporated to 2 mL to remove solvent followed by a further reduction in volume to 0.5 mL under N2. The extract was cleaned up on a preconditioned (details given) activated silica gel column (30 m x 1 cm i.d.; 8 g). Elution was effected with 25 mL hexane followed by 40 mL hexane/CH2Cl2 (4:1); the solvent of the second fraction was removed via a rotary evaporator. The residue was dissolved in methanol and made up to 10 mL. Samples without clean up were filtered. Portions (20 l) of the solutions were analyzed on a 5 m Hypersil Green PAH column (10 cm x 4.6 mm i.d.) operated at 22°C with gradient elution (1 ml/min). Detection was by fluorescence (wavelengths tabulated). Calibration graphs were linear from 0.01-1.2 ng/l for 13 PAH and detection limits ranged from fluoranthene (0.012 pg/l) and 0.45 g/l (naphthalene). Results were compared with those obtained by GC.
Environmental HPLC Fluorescence Post-column derivatization