Matsui Taiki, Fukazawa Kodai, Fujimoto Masatoshi, Imasaka Totaro
Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, Nishi, Fukuoka, Japan.
Anal Sci. 2012;28(5):445-50. doi: 10.2116/analsci.28.445.
A low-energy, high-repetition-rate picosecond laser (40 µJ, 20 kHz, 258 nm) was used for multiphoton ionization (MPI) in gas chromatography/time-of-flight mass spectrometry to quantitatively determine dioxins (DXNs) and polycyclic aromatic hydrocarbons (PAHs). The sensitivity of the technique was compared with that obtained using a high-energy, low-repetition-rate femtosecond laser (86 µJ, 1 kHz, 261 nm). The limits of detection (LODs) for the picosecond laser were several femtograms for chlorinated DXNs with low numbers of chloro substituents, and were several times lower than values obtained using a femtosecond laser, although the LODs were increased, reaching values that were nearly identical to those for the femtosecond laser for octachlorodibenzo-p-dioxin (octaCDD) and octachlorodibenzofuran (octaCDF). The LODs were also measured for 16 PAHs specified by the United States Environmental Protection Agency; the values for half of these compounds were at sub-femtogram levels. The procedure was used to analyze a surface-water sample collected from a river.
采用低能量、高重复频率的皮秒激光（40 μJ，20 kHz，258 nm）在气相色谱/飞行时间质谱中进行多光子电离（MPI），以定量测定二噁英（DXNs）和多环芳烃（PAHs）。将该技术的灵敏度与使用高能量、低重复频率的飞秒激光（86 μJ，1 kHz，261 nm）所获得的灵敏度进行了比较。皮秒激光对含氯取代基数量较少的氯化二噁英的检测限为几飞克，且比使用飞秒激光获得的值低几倍，不过八氯二苯并对二噁英（八氯二噁英）和八氯二苯并呋喃（八氯二苯并呋喃）的检测限有所增加，达到了与飞秒激光几乎相同的值。还对美国环境保护局指定的16种多环芳烃的检测限进行了测定；其中一半化合物的值处于亚飞克水平。该方法用于分析从河流采集的地表水样品。
