Chen Y C, Tsai M F
Institute of Toxicology, Tzu Chi University, Hualien 970, Taiwan.
J Mass Spectrom. 2000 Nov;35(11):1278-84. doi: 10.1002/1096-9888(200011)35:11<1278::AID-JMS59>3.0.CO;2-Z.
The effect of surface activity in surface-assisted laser desorption/ionization (SALDI) mass spectrometry was examined. Several surfactants, including p-tolunensulfonic acid (PTSA), sodium dodecyl sulfate and alkyltrimethylammonium bromide, were used as analytes or additives in the SALDI matrix to demonstrate the surface activity effect. The experimental results demonstrate that analytes that have good surface activity have good sensitivity. Adding suitable amounts of surfactants to the SALDI matrix can dramatically enhance the sensitivity of analytes lacking surface activity. We propose that the enhancement of analyte signals is due to the ionic interaction between ionic surfactants and analytes because non-ionic surfactant additives in the SALDI matrix do not affect the analyte signals. The detection limit of methylephedrine can be as low as 100 pg in the SALDI analysis of 0.5 M PTSA additive in the SALDI matrix. Although other surfactants can also be used as matrix additives to enhance the analyte signal, they do not improve the ion abundance as much as PTSA does.
研究了表面辅助激光解吸/电离（SALDI）质谱中的表面活性效应。几种表面活性剂，包括对甲苯磺酸（PTSA）、十二烷基硫酸钠和烷基三甲基溴化铵，被用作SALDI基质中的分析物或添加剂，以证明表面活性效应。实验结果表明，具有良好表面活性的分析物具有良好的灵敏度。向SALDI基质中添加适量的表面活性剂可以显著提高缺乏表面活性的分析物的灵敏度。我们认为分析物信号的增强是由于离子表面活性剂与分析物之间的离子相互作用，因为SALDI基质中的非离子表面活性剂添加剂不会影响分析物信号。在SALDI基质中添加0.5 M PTSA的SALDI分析中，甲基麻黄碱的检测限可低至100 pg。虽然其他表面活性剂也可用作基质添加剂来增强分析物信号，但它们对离子丰度的改善不如PTSA。
