title: Matrix-Assisted Ionization-Ion Mobility Spectrometry-Mass Spectrometry: Selective Analysis of a Europium-PEG Complex in a Crude Mixture.
abstract: The analytical utility of a new and simple to use ionization method, matrix-assisted ionization (MAI), coupled with ion mobility spectrometry (IMS) and mass spectrometry (MS) is used to characterize a 2-armed europium(III)-containing poly(ethylene glycol) (Eu-PEG) complex directly from a crude sample. MAI was used with the matrix 1,2-dicyanobenzene, which affords low chemical background relative to matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI). MAI provides high ion abundance of desired products in comparison to ESI and MALDI. Inductively coupled plasma-MS measurements were used to estimate a maximum of 10% of the crude sample by mass was the 2-arm Eu-PEG complex, supporting evidence of selective ionization of Eu-PEG complexes using the new MAI matrix, 1,2-dicyanobenzene. Multiply charged ions formed in MAI enhance the IMS gas-phase separation, especially relative to the singly charged ions observed with MALDI. Individual components are cleanly separated and readily identified, allowing characterization of the 2-arm Eu-PEG conjugate from a mixture of the 1-arm Eu-PEG complex and unreacted starting materials. Size-exclusion chromatography, liquid chromatography at critical conditions, MALDI-MS, ESI-MS, and ESI-IMS-MS had difficulties with this analysis, or failed. Graphical Abstract ᅟ.
authors.affiliation: Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA.
authors.forename: Joshua L
authors.initials: JL
authors.lastname: Fischer
authors.affiliation: Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA.
authors.forename: Corinne A
authors.initials: CA
authors.lastname: Lutomski
authors.affiliation: Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA.
authors.forename: Tarick J
authors.initials: TJ
authors.lastname: El-Baba
authors.affiliation: Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA.
authors.forename: Buddhima N
authors.initials: BN
authors.lastname: Siriwardena-Mahanama
authors.affiliation: BAM Federal Institute for Materials Research and Testing, D-12489, Berlin, Germany.
authors.forename: Steffen M
authors.initials: SM
authors.lastname: Weidner
authors.affiliation: BAM Federal Institute for Materials Research and Testing, D-12489, Berlin, Germany.
authors.forename: Jana
authors.initials: J
authors.lastname: Falkenhagen
authors.affiliation: Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA.
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Allen
authors.affiliation: Department of Chemistry, Wayne State University, Detroit, MI, 48202, USA. strimpin@chem.wayne.edu.|MSTM, LLC, Newark, DE, 19711, USA. strimpin@chem.wayne.edu.
authors.forename: Sarah
authors.initials: S
authors.lastname: Trimpin
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods; D056831:Coordination Complexes / Q000032:analysis*; D004867:Equipment Design; D005063:Europium / Q000032:analysis*; D009570:Nitriles / Q000737:chemistry; D011092:Polyethylene Glycols / Q000032:analysis*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000295:instrumentation / Q000379:methods*
chemical_list: D056831:Coordination Complexes; D009570:Nitriles; D011092:Polyethylene Glycols; D005063:Europium; C047080:1,2-benzenedicarbonitrile
keywords: Electrospray ionization; Europium; Inductively coupled plasma-mass spectrometry; Liquid chromatography at critical conditions; Matrix-assisted laser desorption/ionization; Poly(ethylene glycol); Selective ionization matrix-assisted ionization ion mobility spectrometry mass spectrometry; Size-exclusion chromatography