LC-MS - Glossary - peptidetesting.cc

LC-MS (Liquid Chromatography-Mass Spectrometry) is an analytical method that combines liquid chromatography separation with mass spectrometry mass measurement to identify compounds in complex samples. It separates dissolved substances, then measures their mass-to-charge ratio, helping identify compounds and spot impurities other methods may miss.

LC-MS separates compounds before mass measurement

In peptide and research chemical testing, LC-MS supports checks for identity, purity, and impurities. Liquid chromatography moves a dissolved sample through a column, where different compounds exit at different times. Mass spectrometry then measures each compound's mass-to-charge ratio, a mass signal used to confirm what the compound is.

This matters because UV-based HPLC mainly shows peaks, not molecular identity. Contaminants can hide or co-elute within one HPLC peak, making an impure sample look pure. LC-MS can show whether a peak matches the target peptide or includes a degradation product or hidden impurity.

LC-MS has clear distinctions and limits

Standard HPLC is often confused with LC-MS but lacks mass measurement for absolute identity confirmation.
GC-MS uses gas to test volatile residual solvents rather than intact peptides, so it is a different method.
ICP-MS measures elemental heavy metals, unlike LC-MS, which focuses on molecular compounds.
LC-MS/MS further fragments the molecule to read its exact amino acid sequence.
LC-MS verifies the molecule itself and does not test biological safety hazards like endotoxins, which require separate testing.

LC-MS separates compounds before mass measurement

LC-MS has clear distinctions and limits

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