Chen Y C, Tsai M F
Institute of Toxicology, Tzu Chi University, Hualien 970, Taiwan.
Rapid Commun Mass Spectrom. 2000;14(23):2300-4. doi: 10.1002/1097-0231(20001215)14:23<2300::AID-RCM166>3.0.CO;2-#.
Previous work has demonstrated that a combination of solid-phase extraction with surface-assisted laser desorption/ionization (SPE-SALDI) mass spectrometry can be applied to the determination of trace nitrophenols in water. An improved method to lower the detection limit of this hyphenated technique is described in this present study. Activated carbon powder is used as both the SPE adsorbent and the SALDI solid in the analysis by SPE-SALDI. The surface of the activated carbon is modified by passing an aqueous solution of a cationic surfactant through the SPE cartridge. The results demonstrate that the sensitivity for nitrophenols in the analysis by SPE-SALDI can be improved by using cationic surfactants to modify the surface of the activated carbon. The detection limit for nitrophenols is about 25 ppt based on a signal-to-noise ratio of 3 by sampling from 100 mL of solution.
先前的研究表明，固相萃取与表面辅助激光解吸/电离（SPE-SALDI）质谱联用技术可用于测定水中的痕量硝基酚。本研究描述了一种降低这种联用技术检测限的改进方法。在SPE-SALDI分析中，活性炭粉末既用作SPE吸附剂，又用作SALDI固体。通过使阳离子表面活性剂水溶液通过SPE小柱来修饰活性炭表面。结果表明，使用阳离子表面活性剂修饰活性炭表面可提高SPE-SALDI分析中对硝基酚的灵敏度。基于从100 mL溶液中取样，信噪比为3时，硝基酚的检测限约为25 ppt。
