title: Polymer-assisted laser desorption/ionization analysis of small molecular weight compounds.
abstract: The use of non-polar, small polymers as matrices for the analysis of low molecular weight compounds in polymer-assisted laser desorption/ionization mass spectrometry (PALDI-MS) is demonstrated. The matrices evaluated were either based on an oligothiophene or a benzodioxin backbone. Metallocenes, polycyclic hydrocarbons, a fluorosurfactant, and a subset of small organic compounds with various functionalities, served as model analytes. The mechanism of ionization charge transfer is discussed and ionization potentials for the matrices in the study have been estimated using density functional theory (DFT) calculations. Some of the results are possibly contradictory to the generally accepted limiting conditions for gas-phase charge-transfer reactions. These results are interpreted in the light of energy pooling. Also a new mass calibration procedure for the low-mass region in positive ion mode is presented, and some aspects of the ionization/desorption process leading to radical cations are studied.
authors.affiliation: Department of Chemistry, Analytical Chemistry, Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
authors.forename: Andreas
authors.initials: A
authors.lastname: Woldegiorgis
authors.forename: Fredrik
authors.initials: F
authors.lastname: von Kieseritzky
authors.forename: Emma
authors.initials: E
authors.lastname: Dahlstedt
authors.forename: Jonas
authors.initials: J
authors.lastname: Hellberg
authors.forename: Tore
authors.initials: T
authors.lastname: Brinck
authors.forename: Johan
authors.initials: J
authors.lastname: Roeraade
mesh_terms: D008970:Molecular Weight; D009930:Organic Chemicals / Q000032:analysis*; D011108:Polymers / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D009930:Organic Chemicals; D011108:Polymers