title: A dopant for improved sensitivity in easy ambient sonic-spray ionization mass spectrometry.
abstract: Recently, 3-nitrobenzonitrile (3-NBN) has been used to improve sensitivity of sonic-spray ionization mass spectrometry. Easy ambient sonic-spray ionization (EASI) is one of the simplest, gentlest and most used spray-based desorption/ionization ambient techniques, but limited sensitivity has been commonly taken as its major drawback. Herein we investigate the use of 3-NBN as a dopant in EASI-MS for improved sensitivity. Using a few typical EASI samples as test cases, the presence of 10 ppm (µg ml(-1) ) of 3-NBN in the spray solvent showed two to fourfold gains in EASI-MS sensitivity as measured both by total ion current and S/N ratios, accompanied with significant reductions in chemical noise. Sensitivity for DESI using 3-NBN as a dopant also improved and dopant DESI versus dopant EASI sensitivities were compared. The use of solvent dopants seems therefore to be a promising strategy to improve sensitivity for spray-based ambient MS techniques. Copyright © 2015 John Wiley & Sons, Ltd.
authors.affiliation: ThoMSon Mass Spectrometry Laboratory, University of Campinas-UNICAMP, Institute of Chemistry, Campinas, São Paulo, 13083-970, Brazil.
authors.forename: Jandyson M
authors.initials: JM
authors.lastname: Santos
authors.affiliation: ThoMSon Mass Spectrometry Laboratory, University of Campinas-UNICAMP, Institute of Chemistry, Campinas, São Paulo, 13083-970, Brazil.
authors.forename: Pedro H
authors.initials: PH
authors.lastname: Vendramini
authors.affiliation: ThoMSon Mass Spectrometry Laboratory, University of Campinas-UNICAMP, Institute of Chemistry, Campinas, São Paulo, 13083-970, Brazil.
authors.forename: Nicolas V
authors.initials: NV
authors.lastname: Schwab
authors.affiliation: ThoMSon Mass Spectrometry Laboratory, University of Campinas-UNICAMP, Institute of Chemistry, Campinas, São Paulo, 13083-970, Brazil.
authors.forename: Marcos N
authors.initials: MN
authors.lastname: Eberlin
authors.affiliation: ThoMSon Mass Spectrometry Laboratory, University of Campinas-UNICAMP, Institute of Chemistry, Campinas, São Paulo, 13083-970, Brazil.
authors.forename: Damila R
authors.initials: DR
authors.lastname: de Morais
mesh_terms: D056804:Biofuels / Q000032:analysis; D004867:Equipment Design; D020404:Glycerophospholipids / Q000032:analysis; D007202:Indicators and Reagents / Q000737:chemistry; D009570:Nitriles / Q000737:chemistry*; D009578:Nitrobenzenes / Q000737:chemistry*; D000069463:Olive Oil / Q000032:analysis; D012997:Solvents / Q000737:chemistry / Q000145:classification; D021241:Spectrometry, Mass, Electrospray Ionization / Q000295:instrumentation / Q000379:methods*
chemical_list: D056804:Biofuels; D020404:Glycerophospholipids; D007202:Indicators and Reagents; D009570:Nitriles; D009578:Nitrobenzenes; D000069463:Olive Oil; D012997:Solvents; C110438:3-nitrobenzonitrile
keywords: 3-nitrobenzonitrile and mass spectrometry; DESI-MS; EASI-MS; dopant