Analytical method · Separation + Identification
Liquid Chromatography–Mass Spectrometry (LC-MS)
A combined technique that separates components by chromatography and then measures them by mass spectrometry.
What is it?
LC-MS couples a liquid-chromatography separation to a mass spectrometer, so components are first resolved over time and then characterised by mass.
What does it measure?
Both separation (retention) and mass information for eluting components.
What type of result does it produce?
Chromatographic and mass data together — a fuller characterisation than either method alone.
What can the result support?
- Separation and mass information in one workflow
- Distinguishing co-eluting components by mass
What can it not establish?
- Biological activity or fitness for use
- A guarantee of every possible impurity being detected
What variables affect the result?
- All HPLC variables plus all MS variables
- Interface and ionisation compatibility
Example output
A separated peak whose identity is supported by its observed mass in the same run.
Common interpretation mistake
Treating a combined method as proof of safety or suitability; it characterises the material, nothing more.
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