title: Identification of polybrominated diphenyl ether metabolites based on calculated boiling points from COSMO-RS, experimental retention times, and mass spectral fragmentation patterns.
abstract: The COnductor-like Screening MOdel for Realistic Solvents (COSMO-RS) was used to predict the boiling points of several polybrominated diphenyl ethers (PBDEs) and methylated derivatives (MeO-BDEs) of monohydroxylated BDE (OH-BDE) metabolites. The linear correlation obtained by plotting theoretical boiling points calculated by COSMO-RS against experimentally determined retention times from gas chromatography-mass spectrometry facilitated the identification of PBDEs and OH-BDEs. This paper demonstrates the applicability of COSMO-RS in identifying unknown PBDE metabolites of 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) and 2,2',4,4',6-pentabromodiphenyl ether (BDE-100). Metabolites of BDE-47 and BDE-100 were formed through individual incubations of each PBDE with recombinant cytochrome P450 2B6. Using calculated boiling points and characteristic mass spectral fragmentation patterns of the MeO-BDE positional isomers, the identities of the unknown monohydroxylated metabolites were proposed to be 2'-hydroxy-2,3',4,4'-tetrabromodiphenyl ether (2'-OH-BDE-66) from BDE-47, and 2'-hydroxy-2,3',4,4',6-pentabromodiphenyl ether (2'-OH-BDE-119) and 4-hydroxy-2,2',3,4',6-pentabromodiphenyl ether (4-OH-BDE-91) from BDE-100. The collective use of boiling points predicted with COSMO-RS, and characteristic mass spectral fragmentation patterns provided a valuable tool toward the identification of isobaric compounds.
authors.affiliation: Department of Chemistry, University at Buffalo, The State University of New York (SUNY) , Buffalo, New York 14260, United States.
authors.forename: Scott
authors.initials: S
authors.lastname: Simpson
authors.forename: Michael S
authors.initials: MS
authors.lastname: Gross
authors.forename: James R
authors.initials: JR
authors.lastname: Olson
authors.forename: Eva
authors.initials: E
authors.lastname: Zurek
authors.forename: Diana S
authors.initials: DS
authors.lastname: Aga
mesh_terms: D065702:Cytochrome P-450 CYP2B6 / Q000737:chemistry / Q000378:metabolism; D055768:Halogenated Diphenyl Ethers / Q000032:analysis* / Q000378:metabolism*; D013058:Mass Spectrometry; D011789:Quantum Theory; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D012997:Solvents / Q000737:chemistry; D013997:Time Factors; D044366:Transition Temperature
chemical_list: D055768:Halogenated Diphenyl Ethers; D011994:Recombinant Proteins; D012997:Solvents; D065702:Cytochrome P-450 CYP2B6