Panne U, Knöller A, Kotzick R, Niessner R
Institute of Hydrochemistry, Technical University of Munich, München, Germany.
Fresenius J Anal Chem. 2000 Feb;366(4):408-14. doi: 10.1007/s002160050083.
A fiber optical sensor system for the determination of polycyclic aromatic hydrocarbons (PAH) on aerosols by laser-induced, time-resolved fluorescence is combined with a thermodesorption device. The sensor system is based on an aerosol flow cell, which is fibre-optically coupled to a pulsed nitrogen laser for excitation and the detection system. Time-resolved fluorescence emission spectra are detected by a monochromator equipped with a photomultiplier and a fast digital storage oscilloscope. The analytical figures of merit of the thermodenuder are reported for benzo[a]pyrene, benzo[b]fluoranthene, and benzo[ghi]-perylene on ultrafine soot and NaCl aerosols. By thermodesorption of the PAH, problems due to quenching of the PAH fluorescence by the bulk aerosol material or excimer formation on the aerosol surface were avoided. For the PAH under study, the sensitivity was improved considerably and detection limits between 110 and 850 ng m(-3) were attained, while a response time of 2-3 min was achieved with the thermodenuder. A calibration for PAH on ultrafine soot and NaCl aerosols was established independent of the aerosol substrate.
一种用于通过激光诱导的时间分辨荧光测定气溶胶中多环芳烃（PAH）的光纤传感器系统与热脱附装置相结合。该传感器系统基于一个气溶胶流通池，它通过光纤与用于激发的脉冲氮激光器以及检测系统耦合。时间分辨荧光发射光谱由配备光电倍增管和快速数字存储示波器的单色仪检测。报告了热脱附器对超细烟尘和氯化钠气溶胶上的苯并[a]芘、苯并[b]荧蒽和苯并[ghi]苝的分析性能指标。通过PAH的热脱附，避免了由于大量气溶胶材料淬灭PAH荧光或在气溶胶表面形成准分子而产生的问题。对于所研究的PAH，灵敏度有了显著提高，检测限达到110至850 ng m(-3)，同时热脱附器的响应时间为2至3分钟。建立了独立于气溶胶基质的超细烟尘和氯化钠气溶胶上PAH的校准方法。
