TY - JOUR
T1 - Selective fluorescence quenching of polynuclear aromatic hydrocarbons in microcolumn liquid chromatography
AU - Chen, Shu Hui
AU - Evans, Christine E.
AU - McGuffin, Victoria L.
N1 - Funding Information:
This research was supported, in part, by the Mic~gan State University Foundation and by the Dow Chemical Company. Preliminary results were reported at the national meeting of the American Chemical Society (Boston, 1990).
PY - 1991/5/15
Y1 - 1991/5/15
N2 - A selective fluorescence quenching method using nitromethane as the quenching agent is systematically studied in the absence and presence of absorption effects. Nitromethane is found to quench the emission intensity of polynuclear aromatic hydrocarbons (PAHs) with six-membered rings, while the emission of PAHs with five-membered rings is essentially unaltered. However, fluorescence attenuation caused by primary and secondary absorption may result in errors in the determination of dynamic quenching constants. In this work, a modified Stern-Volmer relationship is developed to distinguish and to compensate mathematically for absorption effects. Utilizing this expression, the Stern-Volmer quenching constant (Kq) is determined to be 125 and 0.15 M-1 for pyrene and fluoranthene, respectively, using nitromethane as the quenching agent in methanol at ambient temperature. Because of the large difference in quenching constants, this analytical methodology is applied for the class-selective identification of PAHs in coal-derived fluids by microcolumn liquid chromatography with laser fluorescence detection.
AB - A selective fluorescence quenching method using nitromethane as the quenching agent is systematically studied in the absence and presence of absorption effects. Nitromethane is found to quench the emission intensity of polynuclear aromatic hydrocarbons (PAHs) with six-membered rings, while the emission of PAHs with five-membered rings is essentially unaltered. However, fluorescence attenuation caused by primary and secondary absorption may result in errors in the determination of dynamic quenching constants. In this work, a modified Stern-Volmer relationship is developed to distinguish and to compensate mathematically for absorption effects. Utilizing this expression, the Stern-Volmer quenching constant (Kq) is determined to be 125 and 0.15 M-1 for pyrene and fluoranthene, respectively, using nitromethane as the quenching agent in methanol at ambient temperature. Because of the large difference in quenching constants, this analytical methodology is applied for the class-selective identification of PAHs in coal-derived fluids by microcolumn liquid chromatography with laser fluorescence detection.
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U2 - 10.1016/S0003-2670(00)80665-0
DO - 10.1016/S0003-2670(00)80665-0
M3 - Article
AN - SCOPUS:0025730245
SN - 0003-2670
VL - 246
SP - 65
EP - 74
JO - Analytica Chimica Acta
JF - Analytica Chimica Acta
IS - 1
ER -