Laser-induced solid-surface room-temperature phosphorimetry of polycyclic aromatic hydrocarbons

Laser-induced solid-surface room-temperature phosphorimetry (SSRTP) has been employed for the detection of polycyclic aromatic hydrocarbons. A nitrogen-pumped laser and a dye laser were used as excitation sources. The effects of sample volume, laser irradiation, and background reduction treatment on the precision and sensitivity of the method were studied. With the use of thallium(I) acetate as a phosphorescence enhancer, picogram limits of detection were estimated for phenanthrene, pyrene, benzo[g,h,i]perylene, chrysene, coronene, and 1,2-benzofluorene. The study demonstrates that laser excitation can improve the sensitivity of SSRTP by up to three orders of magnitude.