Charge competition and the linear dynamic range of detection in electrospray ionization mass spectrometry
Charge competition and the linear dynamic range of detection in electrospray ionization mass spectrometry
复制标题
DOI：
10.1016/j.jasms.2004.04.034
复制
发表时间：
2004-10-01
影响因子：
3.2
通讯作者：
Smith, RD
中科院分区：
文献类型：
--
作者：
Tang, KQ;Page, JS;Smith, RD
对电喷雾电离过程中的电荷竞争及其对电喷雾电离质谱线性动态范围的影响进行了实验研究和理论分析。实验证实，随着电喷雾流量的降低，MS的灵敏度预期会增加。然而，不同的化合物即使在最低的流速、相同的浓度和电喷雾操作条件下也表现出略有不同的质谱峰强度。每种化合物溶液的MS响应在较低浓度下表现出良好的线性，在较高浓度下表现出较低的水平，与ESI过程中分析物的“饱和”一致。在ESI过程中导致饱和的电荷竞争程度与电喷雾中过剩电荷相对于溶液中分析物分子总数的相对大小是一致的。该ESI容量模型允许人们预测电荷竞争和电离抑制效应的样品浓度极限，以及ESI-MS的线性动态范围。讨论了定量MS分析的含义和有效扩展ESI测量动态范围的可能性。(C)2004年美国质谱学学会。
An experimental investigation and theoretical analysis are reported on charge competition in electrospray ionization (ESI) and its effects on the linear dynamic range of ESI mass spectrometric (MS) measurements. The experiments confirmed the expected increase of MS sensitivities as the ESI flow rate decreases. However, different compounds show somewhat different mass spectral peak intensities even at the lowest flow rates, at the same concentration and electrospray operating conditions. MS response for each compound solution shows good linearity at lower concentrations and levels off at high concentration, consistent with analyte "saturation" in the ESI process. The extent of charge competition leading to saturation in the ESI process is consistent with the relative magnitude of excess charge in the electrospray compared to the total number of analyte molecules in the solution. This ESI capacity model allows one to predict the sample concentration limits for charge competition and the on-set of ionization suppression effects, as well as the linear dynamic range for ESI-MS. The implications for quantitative MS analysis and possibilities for effectively extending the dynamic range of ESI measurements are discussed. (C) 2004 American Society for Mass Spectrometry.