Belov M E, Gorshkov M V, Udseth H R, Anderson G A, Smith R D
Environmental Molecular Sciences Laboratory, Richland, Washington 99352, USA.
Anal Chem. 2000 May 15;72(10):2271-9. doi: 10.1021/ac991360b.
Methods are being developed for ultrasensitive protein characterization based upon electrospray ionization (ESI) with Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). The sensitivity of a FTICR mass spectrometer equipped with an ESI source depends on the overall ion transmission, which combines the probability of ionization, transmission efficiency, and ion trapping in the FTICR cell. Our developments implemented in a 3.5 tesla FTICR mass spectrometer include introduction and optimization of a newly designed electrodynamic ion funnel in the ESI interface, improving the ion beam characteristics in a quadrupole-electrostatic ion guide interface, and modification of the electrostatic ion guide. These developments provide a detection limit of approximately 30 zmol (approximately 18,000 molecules) for proteins with molecular weights ranging from 8 to 20 kDa.
基于电喷雾电离（ESI）与傅里叶变换离子回旋共振质谱（FTICR-MS）的超灵敏蛋白质表征方法正在开发中。配备ESI源的FTICR质谱仪的灵敏度取决于整体离子传输，这结合了电离概率、传输效率以及在FTICR池中离子捕获的情况。我们在一台3.5特斯拉FTICR质谱仪中实施的改进包括在ESI接口中引入并优化新设计的电动离子漏斗、改善四极-静电离子导向接口中的离子束特性以及对静电离子导向进行改造。这些改进为分子量在8至20 kDa范围内的蛋白质提供了约30 zmol（约18,000个分子）的检测限。
