Liquid chromatography
Separate components first.
The LC stage reduces complexity by chromatographically separating sample components, supporting subsequent mass-spectrometric characterisation.
Analytical Methods
LC-MS
LC-MS combines liquid chromatography with mass spectrometry, allowing sample components to be separated and then characterised by mass-spectrometric signals.
Mass spectrometry
Interpret signals by mass and charge.
Mass-spectrometric data are based on ions and their mass-to-charge ratios. For identity assessment, the key question is how those signals are matched against the expected molecular structure.
Read the report
Identity is more than a single peak.
Sample / batch
Check that the tested sample corresponds to the stated batch.
LC separation
Liquid chromatography separates components before or while they are assessed by mass spectrometry.
m/z data
Mass spectrometry characterises ions by their mass-to-charge ratio.
Expected identity
The report should make it clear how measured signals correspond to the expected molecular identity.
Limits of the result
LC-MS does not automatically replace quantitative amount determination, sterility testing or endotoxin testing.
LC-MS
IUPAC Gold Book · Liquid chromatography-mass spectrometryIUPAC mass-spectrometry terminology
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