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Data Types
Ion Polarity Modes
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TSQ Altis, Quantis, and Fortis Hardware Manual
Thermo Scientific
Ion Polarity Modes
The TSQ Altis, TSQ Quantis, and TSQ Fortis MSs can operate in either positive or negative
ion polarity mode. You can obtain positive ion or negative ion or positive/negative ion mass
spectra.The MS controls whether positive ions or negative ions are transmitted to the mass
analyzer for mass analysis by changing the polarity of the voltage potentials applied to the API
source, ion optics, and ion detection system.
The information obtained from a positive ion mass spectrum is different from and
complementary to the information from a negative ion spectrum. Therefore, the ability to
obtain both positive ion and negative ion mass spectra aids you in the qualitative analysis of
your sample. You can choose the ion polarity mode and ionization mode to obtain maximum
sensitivity for the particular analyte of interest.
