Mass Analyzer

The key variable is m/z, not mass alone. After ionization, electric and magnetic fields alter ion motion, so ions with different mass-to-charge ratios follow different trajectories. In analyzer designs based on trapping, controlled conditions instead stabilize selected m/z values. This selective behavior allows the instrument to distinguish chemical species before their signals reach the detector.

These analyzer types apply different separation principles to the ions produced during mass spectrometry. Quadrupole, time-of-flight, ion-trap, and Orbitrap designs therefore provide distinct combinations of resolution, speed, and mass range rather than identical performance. The appropriate choice depends on which measurement characteristics matter most for the chemical analysis, such as distinguishing closely related species or surveying a broader range.

Resolution, speed, and mass range describe complementary aspects of analyzer performance. Resolution affects how effectively chemical species can be distinguished, speed influences how rapidly measurements can be obtained, and mass range determines the span of m/z values accessible to the measurement. Because analyzer designs combine these properties differently, selection should reflect the analytical question and sample requirements.

Ionization first creates the ions that the analyzer can examine. The Mass Analyzer then directs those ions through electric or magnetic fields, or applies controlled ion-trapping conditions, to separate or stabilize selected m/z values. A detector records the resulting ion signals, converting the analyzer's separation behavior into measurable information about chemical species.

Chemists use analyzer-based measurements when they need to distinguish chemical species and compare their ion signals. The resulting data can support compound identification as well as isotope-ratio measurements, where signals associated with isotopic species are evaluated. These capabilities make mass analyzers useful for characterizing chemical composition rather than merely detecting that a sample produces ions.

In structural analysis, separated ion signals provide information that helps researchers examine chemical species within a sample. For quantitative assays, the measured signals support determination of chemical amounts, including in complex samples. These applications extend the role of the analyzer from ion separation to chemically relevant interpretation, linking instrument measurements with identification, composition, and measurement tasks.