High-accuracy microanaiysis-LC-MS~n:Hitachi M-8000 LC-MS system with sonic spray ionization

摘要

In 1994, Hirabayshi et al developed a sonic spray ionization (SSI) interface for LC-MS system.In this technique, a sample solution in sprayed from a sample introduction capillary by a high-speed nitrogen gas flow that is coaxial to the capillary, and ions of chemicals in the solution as well as charged droplets are produced at room temperature and atmospheric pressure. The LC-Ms with SSI system possesses following major features: (1) Ionization is performed with high efficiency by the sonic spray technique; (2) Since high voltage is not required, highly polar solvents may be introduced to permit mass analysis without alteration of the standard separation conditions for physiological components; (3) Since heating is not required, thermally unstable polysaccharides, proteins and peptides, which have been difficult to analyze using conventional ionization methods, can now be analyze with high sensitivity; (4) Mass spectrum: pseudo molecular ions [M+Na]+ are detected at high sensitivity levels; and (5) The MS/MS methodology is especially useful for obtaining structural information. In the system with SSI, MS/MS method can be developed quickly with very little effort. In this paper, The SSI technique and the major features of M-8000 LC/MS 3DQ system are introduced.