Moskovets E, Preisler J, Chen H S, Rejtar T, Andreev V, Karger B L
Barnett Institute, Northeastern University, Boston, Massachusetts 02115, USA.
Anal Chem. 2006 Feb 1;78(3):912-9. doi: 10.1021/ac051393t.
A high-throughput axial MALDI-TOF mass spectrometer utilizing a laser with a 2-kHz pulse repetition-rate was constructed and tested. This fast mass spectrometer provided a data acquisition rate 10 times faster than a commercially available (200 Hz) axial mass spectrometer, while maintaining comparable limits of detection (200 amol of Glu fib peptide). Mass resolution, only slightly less than the commercial instrument (10 000 vs 14 000), was sufficient for baseline resolution of isotopic clusters of peptides with m/z <2700. A new method of mass calibration, which combined a limited number of internal and external standards, provided the same 15 ppm mass accuracy over the entire sample plate on either instrument. Implementing the 2-kHz laser required a faster data acquisition system and high-voltage pulse electronics, together with a novel strategy for rapid sample plate movements during acquisition, to achieve a sample analysis rate of up to 2 spots/s (with 800 shots/spot). The overall performance of the fast MALDI-TOF MS instrument was demonstrated by the acquisition, in 12 min, of an LC-MS data set from a plate of 625 fractions collected during LC separation of an 16O/18O differentially labeled proteomic sample of a tryptic digest of an E. coli lysate.
构建并测试了一台采用2 kHz脉冲重复率激光的高通量轴向基质辅助激光解吸电离飞行时间质谱仪。这台快速质谱仪的数据采集速率比市售（200 Hz）轴向质谱仪快10倍，同时保持了相当的检测限（200 amol的Glu纤维肽）。质量分辨率略低于商用仪器（10000对14000），但足以对m/z <2700的肽同位素簇进行基线分辨。一种结合了有限数量内标和外标的质量校准新方法，在两台仪器的整个样品板上都提供了相同的15 ppm质量准确度。采用2 kHz激光需要更快的数据采集系统和高压脉冲电子设备，以及一种在采集过程中快速移动样品板的新策略，以实现高达2个点/秒的样品分析速率（每个点800次射击）。通过在12分钟内从一块包含625个馏分的板上采集LC-MS数据集，展示了快速基质辅助激光解吸电离飞行时间质谱仪的整体性能，这些馏分是在对大肠杆菌裂解物的胰蛋白酶消化产物进行16O/18O差异标记的蛋白质组样品的LC分离过程中收集的。
