title: Benzene-assisted atmospheric-pressure chemical ionization: a new liquid chromatography/mass spectrometry approach to the analysis of selected hydrophobic compounds.
abstract: Charge-exchange reactions involving benzene have been successfully exploited to increase the sensitivity of atmospheric-pressure chemical ionization mass spectrometry (APCI-MS) towards hydrophobic compounds of significant environmental relevance which are not detectable with the ordinary APCI techniques. Among them, good sensitivity have been found for (a) highly chlorinated biphenyl derivatives such as dichlorodiphenyltrichloroethane (DDT), dichlorodiphenyldichloroethane (DDD) and dichlorodiphenyldichloroethene (DDE); (b) cyclopentadienes such as Aldrin and its epoxy derivatives Dieldrin and Endrin; and (c) dibenzofurans and dibenzo-para-dioxins such as 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF) and 2,3,7,8-tetrachloro-dibenzo-para-dioxin (2,3,7,8-TCDD). The reactant benzene molecules were introduced into the source either through the nebulizer gas or by direct post-column addition of neat liquid, whereas the targeted compounds were analyzed using a high-performance liquid chromatography (HPLC) RP-18 column using methanol/water solutions as mobile phase. By using benzene as post-column reagent, positive ion mode detection was proven to be significantly enhanced as compared with APCI measurements carried out without benzene assistance.
authors.affiliation: Dipartimento di Fisica, Laboratorio di Chimica Bioorganica, Università di Trento, 38050 Via Sommarive 14, Povo-Trento, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Perazzolli
authors.forename: Ines
authors.initials: I
authors.lastname: Mancini
authors.forename: Graziano
authors.initials: G
authors.lastname: Guella
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D000452:Aldrin / Q000031:analogs & derivatives / Q000032:analysis; D001272:Atmosphere; D001554:Benzene / Q000737:chemistry*; D001572:Benzofurans; D002851:Chromatography, High Pressure Liquid; D003634:DDT / Q000032:analysis; D003633:Dichlorodiphenyl Dichloroethylene / Q000032:analysis; D003632:Dichlorodiphenyldichloroethane / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods*; D057927:Hydrophobic and Hydrophilic Interactions; D000072317:Polychlorinated Dibenzodioxins / Q000032:analysis; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D000393:Air Pollutants; D001572:Benzofurans; D000072317:Polychlorinated Dibenzodioxins; D003633:Dichlorodiphenyl Dichloroethylene; D003634:DDT; D001554:Benzene; D000452:Aldrin; D003632:Dichlorodiphenyldichloroethane; C014211:2,3,7,8-tetrachlorodibenzofuran