Determination of polycyclic aromatic hydrocarbons with molecular weight 302 in water samples by solid-phase nano-extraction and laser excited time-resolved shpol'skii spectroscopy
Abbreviated Journal Title
MULTIDIMENSIONAL FLUORESCENCE SPECTROSCOPY; STANDARD REFERENCE; MATERIALS; DIBENZOPYRENE ISOMERS; ENVIRONMENTAL-SAMPLES; LIQUID-CHROMATOGRAPHY; MATRICES; IDENTIFICATION; SPECTROMETRY; TEMPERATURE; HPLC; Chemistry, Analytical
Monitoring of high-molecular weight polycyclic aromatic hydrocarbons (HMW-PAH) via simple and cost effective methods still remains a challenge. In this article, we combine solid-phase nano-extraction (SPNE) and 4.2 K laser-excited time resolved Shpol'skii spectroscopy (LETRSS) into a valuable alternative for the water analysis of dibenzo[a, l] pyrene, dibenzo[a, h] pyrene, dibenzo[a,i] pyrene and naphtho[2,3-a] pyrene. In comparison to the original SPNE procedure, the present method improves PAH recoveries and reduces extraction time from 30 to 20 min per sample. Quantitative release of HMW-PAH into the Shpol'skii matrix (n-octane) is best accomplished with a mixture of 48 mu L of methanol and 2 mu L of 1-pentanethiol. Their migration into the 50 mu L layer of n-octane provides highly resolved spectra with distinct fluorescence lifetimes for unambiguous isomer determination. Complete analysis takes less than 30 min per sample and consumes only 100 micro-liters of organic solvents. 500 mu L of water are sufficient to obtain limits of detection ranging from 16 ng L(-1) (dibenzo[a, l] pyrene) to 55 ng L(-1) (dibenzo[a, i] pyrene), relative standard deviations better than 3% and analytical recoveries above 90%. Although a straightforward comparison to chromatographic methods is not possible because of the lack of analytical figures of merit on HMW-PAH, the excellent precision of measurements, limits of detection and overall recoveries makes SPNE-LETRSS an attractive approach to water analysis of HMW-PAH.
"Determination of polycyclic aromatic hydrocarbons with molecular weight 302 in water samples by solid-phase nano-extraction and laser excited time-resolved shpol'skii spectroscopy" (2011). Faculty Bibliography 2010s. 2099.