Williams D Keith, Kovach Alexander L, Muddiman David C, Hanck Kenneth W
W. M. Keck FT-ICR Mass Spectrometry Laboratory, Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, USA.
J Am Soc Mass Spectrom. 2009 Jul;20(7):1303-10. doi: 10.1016/j.jasms.2009.02.030. Epub 2009 Mar 11.
Fourier transform ion cyclotron resonance mass spectrometry has the ability to realize exceptional mass measurement accuracy (MMA); MMA is one of the most significant attributes of mass spectrometric measurements as it affords extraordinary molecular specificity. However, due to space-charge effects, the achievable MMA significantly depends on the total number of ions trapped in the ICR cell for a particular measurement, as well as relative ion abundance of a given species. Artificial neural network calibration in conjunction with automatic gain control (AGC) is utilized in these experiments to formally account for the differences in total ion population in the ICR cell between the external calibration spectra and experimental spectra. In addition, artificial neural network calibration is used to account for both differences in total ion population in the ICR cell as well as relative ion abundance of a given species, which also affords mean MMA values at the parts-per-billion level.
傅里叶变换离子回旋共振质谱仪能够实现极高的质量测量精度(MMA);MMA是质谱测量最重要的属性之一,因为它提供了非凡的分子特异性。然而,由于空间电荷效应,可实现的MMA显著取决于特定测量中捕获在ICR池中离子的总数,以及给定物种的相对离子丰度。在这些实验中,结合自动增益控制(AGC)的人工神经网络校准被用于正式考虑外部校准光谱和实验光谱之间ICR池中总离子数的差异。此外,人工神经网络校准用于考虑ICR池中总离子数的差异以及给定物种的相对离子丰度,这也能提供十亿分之一水平的平均MMA值。