Kwon J Y, Moini M
Department of Chemistry and Biochemistry, University of Texas at Austin, 78712, USA.
J Am Soc Mass Spectrom. 2001 Jan;12(1):117-22. doi: 10.1016/S1044-0305(00)00206-3.
A dual oscillating capillary nebulizer (OCN) in conjunction with an atmospheric pressure microwave induced plasma ionization (AP-MIPI) source was applied to the analysis of underivatized amino acid mixtures. It was found that, compared to the single OCN, the dual OCN enhanced the sensitivity of detection several fold. Enhanced sensitivity was compound dependent. For small molecules, such as amino acids, it was 2-5 times more sensitive, while for larger molecules such as peptides it was more than an order of magnitude. The increase in sensitivity was attributed to the enhanced nebulization of the new torch. By using water/ acetonitrile containing 0.1% nonafluoropentanoic acid as the high performance liquid chromatography (HPLC) mobile phase and a C18 column, all common amino acids were separated and detected. A comparison between the results obtained using microwave induced plasma, atmospheric pressure chemical ionization (APCI), and electrospray ionization (ESI) at flow rates compatible with micro LC (10-100 microL/min) showed a higher sensitivity of detection with the AP-MIPI technique for the analysis of underivatized amino acids.
一种双振荡毛细管雾化器（OCN）与大气压微波诱导等离子体电离（AP-MIPI）源相结合，用于分析未衍生化的氨基酸混合物。结果发现，与单振荡毛细管雾化器相比，双振荡毛细管雾化器将检测灵敏度提高了几倍。灵敏度的提高取决于化合物。对于小分子，如氨基酸，其灵敏度提高了2至5倍，而对于较大分子，如肽，则提高了一个数量级以上。灵敏度的提高归因于新型炬管雾化效果的增强。通过使用含有0.1%全氟戊酸的水/乙腈作为高效液相色谱（HPLC）流动相，并使用C18柱，所有常见氨基酸均被分离并检测。在与微液相色谱兼容的流速（10 - 100微升/分钟）下，对使用微波诱导等离子体、大气压化学电离（APCI）和电喷雾电离（ESI）获得的结果进行比较，结果表明，AP-MIPI技术在分析未衍生化氨基酸时具有更高的检测灵敏度。
