Wilkes J G, Zarrin F, Lay J O, Vestal M L
USFDA, National Center for Toxicological Research, Jefferson, Arizona 72079.
Rapid Commun Mass Spectrom. 1995;9(2):133-7. doi: 10.1002/rcm.1290090206.
We characterized the particle size distribution and the analyte transmission efficiency of a liquid chromatography/particle beam/mass spectrometry (LC/PB/MS) system as a function of experimental variations normally used to optimize the LC/PB/MS system. The particle size distribution was evaluated using an electrical differential mobility particle sizer (DMPS) and both the DMPS and the mass spectrometer were used to evaluate transmission. The latter results were correlated to provide evidence related to mechanisms which contribute to poor sample transmission. Addition of ammonium acetate buffer did not increase the aerosol particle mean diameter. However, it did lead to significant increases in caffeine transmission efficiency observed in both the DMPS and the mass spectrometer. Our results were interpreted to suggest a possible electrostatic cause for quantitative anomalies in LC/PB/MS rather than simple mass discrimination in the particle beam momentum separator.
我们将液相色谱/粒子束/质谱（LC/PB/MS）系统的粒径分布和分析物传输效率表征为通常用于优化LC/PB/MS系统的实验变量的函数。使用电微分迁移率粒度分析仪（DMPS）评估粒径分布，并使用DMPS和质谱仪评估传输。将后者的结果进行关联，以提供与导致样品传输不佳的机制相关的证据。添加醋酸铵缓冲液并未增加气溶胶颗粒的平均直径。然而，它确实导致在DMPS和质谱仪中观察到的咖啡因传输效率显著提高。我们的结果被解释为表明LC/PB/MS中定量异常可能存在静电原因，而非粒子束动量分离器中的简单质量歧视。
