title: Analyses of polycyclic aromatic hydrocarbons in seafood by capillary electrochromatography-atmospheric pressure chemical ionization/mass spectrometry.
abstract: In this work, an on-line preconcentration capillary electrochromatographic (CEC) separation coupled with atmospheric pressure chemical ionization-mass spectrometry (APCI-MS) was used for 16 PAHs analyses, in which poly(stearyl methacrylate-divinylbenzene) (poly(SMA-DVB)) monolith was used as the separation column. With variations in the effective length of poly(SMA-DVB) monolith as well as the volume fraction of acetonitrile (ACN) in the mobile phase, both separation and resolution were improved. A poly(SMA-DVB) monolith of 50-cm effective length (i.e. 50-cm column length filled with polymer) and a two-step step-gradient elution (by changing the ACN levels of the mobile phase starting with an initial of 70% up to 80% with 30-min time interval), which provided baseline separation for PAHs solutes (except for chrysene and benzo[a]anthracene) within 50 min, were employed as the optimal chromatographic conditions. In contrast to the other mass spectrometer parameters (nebulizer gas pressure, vaporizer temperature, corona current) as well as on-line preconcentration parameter (the ACN level in the sample matrix), the sheath liquid composition (methanol/water in the ratio of 3:1) and the sample injection time (40 min) were found as the predominant factors that control the sensitivity of PAHs determination. Finally, this on-line preconcentration CEC-APCI-MS method determined PAH residues in seafood samples successfully with as low as 10 ng/g level.
authors.affiliation: Department of Chemistry, Chung Yuan Christian University, 200 Chung Pei Road, Chung-Li 320, Taiwan.
authors.forename: Yi-Jie
authors.initials: YJ
authors.lastname: Cheng
authors.forename: Sing-Hao
authors.initials: SH
authors.lastname: Huang
authors.forename: Ju-Yin
authors.initials: JY
authors.lastname: Chiu
authors.forename: Wan-Ling
authors.initials: WL
authors.lastname: Liu
authors.forename: Hsi-Ya
authors.initials: HY
authors.lastname: Huang
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000818:Animals; D053801:Capillary Electrochromatography / Q000379:methods*; D057230:Limit of Detection; D013058:Mass Spectrometry / Q000379:methods*; D010125:Ostreidae / Q000737:chemistry; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D015203:Reproducibility of Results; D017747:Seafood / Q000032:analysis*
chemical_list: D000097:Acetonitriles; D011084:Polycyclic Aromatic Hydrocarbons; C032159:acetonitrile
keywords: Atmospheric pressure chemical ionization-mass spectrometry; Capillary electrochromatography; Monolithic column; Polycyclic aromatic hydrocarbons