title: Volatile polydimethylcyclosiloxanes in the ambient laboratory air identified as source of extreme background signals in nanoelectrospray mass spectrometry.
abstract: Polydimethylcyclosiloxanes, an almost ubiquitous air contaminant, can interfere with nanoelectrospray analysis. The sensitivity of nanoelectrospray to these volatile air contaminants was demonstrated in this study. The intensity of the interfering ion signals caused by these compounds can be decreased by changing the position of the nanoESI needle and almost completely suppressed by applying a flow of pure nitrogen around the needle and the sample cone. The nitrogen flow causes a slight shift in charge distribution, but does not influence the sensitivity for peptide detection.
authors.affiliation: Institute of Medical Immunology, Charité, Humboldt University, Hessische Strasse 3-4, 10115 Berlin, Germany. andreas.schlosser@charite.de
authors.forename: Andreas
authors.initials: A
authors.lastname: Schlosser
authors.forename: Rudolf
authors.initials: R
authors.lastname: Volkmer-Engert
mesh_terms: D000388:Air; D000393:Air Pollutants / Q000032:analysis / Q000737:chemistry; D016477:Artifacts; D004129:Dimethylpolysiloxanes / Q000032:analysis / Q000737:chemistry; D005345:Fibrinopeptide B / Q000032:analysis*; D007753:Laboratories; D009584:Nitrogen; D012680:Sensitivity and Specificity; D012833:Siloxanes / Q000032:analysis* / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods / Q000592:standards*; D014835:Volatilization
chemical_list: D000393:Air Pollutants; D004129:Dimethylpolysiloxanes; D012833:Siloxanes; D005345:Fibrinopeptide B; D009584:Nitrogen