title: Accurate mass measurement by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. II. Measurement of negative radical ions using porphyrin and fullerene standard reference materials.
abstract: A method for the accurate mass measurement of negative radical ions by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOFMS) is described. This is an extension to our previously described method for the accurate mass measurement of positive radical ions (Griffiths NW, Wyatt MF, Kean SD, Graham AE, Stein BK, Brenton AG. Rapid Commun. Mass Spectrom. 2010; 24: 1629). The porphyrin standard reference materials (SRMs) developed for positive mode measurements cannot be observed in negative ion mode, so fullerene and fluorinated porphyrin compounds were identified as effective SRMs. The method is of immediate practical use for the accurate mass measurement of functionalised fullerenes, for which negative ion MALDI-TOFMS is the principal mass spectrometry characterisation technique. This was demonstrated by the accurate mass measurement of six functionalised C(60) compounds.
authors.affiliation: EPSRC National Mass Spectrometry Service Centre (NMSSC), Institute of Mass Spectrometry (IMS), School of Medicine, Swansea University, Singleton Park, Swansea SA2 8PP, UK.
authors.forename: Zhecheng
authors.initials: Z
authors.lastname: Shao
authors.forename: Mark F
authors.initials: MF
authors.lastname: Wyatt
authors.forename: Bridget K
authors.initials: BK
authors.lastname: Stein
authors.forename: A Gareth
authors.initials: AG
authors.lastname: Brenton
mesh_terms: D000838:Anions / Q000737:chemistry; D017611:Fluorine Compounds / Q000737:chemistry; D037741:Fullerenes / Q000737:chemistry*; D011166:Porphyrins / Q000737:chemistry*; D012015:Reference Standards; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods / Q000592:standards
chemical_list: D000838:Anions; D017611:Fluorine Compounds; D037741:Fullerenes; D011166:Porphyrins