mass spectrometry assay tandem mass spectrometry assay Hector Guzman-Orozco, ORCID:0000-0003-3430-8997 tandem mass spectrometry assay http://purl.obolibrary.org/obo/OBI_0200198 https://github.com/obi-ontology/obi/issues/1506 A precursor ion is selected in the first stage, allowed to fragment and then all resultant masses are scanned in the second mass analyzer and detected in the detector that is positioned after the second mass analyzer. This experiment is commonly performed to identify transitions used for quantification by tandem MS. Discussed on the OBI developer call 2022-03-07: 'tandem mass spectrometry' OBI:0200198 is under 'data transformation' but is actually defined like an assay. Moving OBI:0200198 from 'data transformation' to 'assay' is a major logical change, so the OBI development team supports obsoleting 'tandem mass spectrometry' OBI:0200198 and replacing it with ‘tandem mass spectrometry assay’ OBI:0003540. A mass spectrometry assay that uses two or more analyzers separated by a region in which ions can be induced to fragment by transfer of energy (frequently by collision with other molecules). metadata complete