O'Connor Peter B, Mirgorodskaya Ekaterina, Costello Catherine E
Mass Spectrometry Resource, Department of Biochemistry, Boston University School of Medicine, Massachusetts 02118, USA.
J Am Soc Mass Spectrom. 2002 Apr;13(4):402-7. doi: 10.1016/S1044-0305(02)00351-3.
Transiently elevating pressure in a matrix-assisted laser desorption/ionization Fourier transform mass spectrometry (MALDI-FTMS) source into the 1-10 mbar range during ionization decreases the metastable fragmentation of gangliosides. This allows detection of the molecular ion species without loss of the highly labile sialic acid residues. In these experiments, gangliosides with up to five sialic acids were ionized by MALDI and detected with the FTMS. In each case, when the high pressure collisional cooling was used, the singly charged molecular ion was the base peak in the spectra, both in the positive and negative ion modes, and minimal metastable fragmentation was observed. This result is promising, as the previously developed TLC separation methods can be coupled to MALDI-FTMS.
在基质辅助激光解吸/电离傅里叶变换质谱（MALDI-FTMS）源中，在电离过程中将压力短暂提升至1-10毫巴范围，可减少神经节苷脂的亚稳碎裂。这使得能够检测到分子离子物种，而不会损失高度不稳定的唾液酸残基。在这些实验中，含有多达五个唾液酸的神经节苷脂通过MALDI进行电离，并使用FTMS进行检测。在每种情况下，当使用高压碰撞冷却时，无论是在正离子模式还是负离子模式下，单电荷分子离子都是光谱中的基峰，并且观察到的亚稳碎裂极少。这一结果很有前景，因为先前开发的薄层色谱分离方法可以与MALDI-FTMS联用。
