title: Analysis of polynitrophenols and hexyl by liquid chromatography-mass spectrometry using atmospheric pressure ionisation methods and a volatile ion-pairing reagent.
abstract: An LC-MS method for the determination of picric acid (2,4,6-trinitrophenol), its reductive transformation products picramic acid (2-amino-4,6-dinitrophenol) and iso-picramic acid (4-amino-2,6-dinitrophenol) and hexyl (2,2',4,4',6,6'-hexanitrodiphenylamine) has been developed. The analytes were separated using ion-pairing chromatography with a volatile ion-pairing reagent suitable for subsequent MS detection. The performance of an atmospheric pressure chemical ionisation (APCI) and an electrospray ionisation (ESI) interface was compared. ESI-MS is more sensitive for the analytes, especially for hexyl and picric acid, APCI-MS delivered more fragments necessary for unequivocal identification. With LC-ESI-MS limits of detection using single ion monitoring (SIM) mode are 4 ng (iso-picramic acid), 800 pg (picramic acid), 400 pg (picric acid) and 80 pg (hexyl). For quantification, 15N-picric acid was used as an internal standard. Using this new method, the degradation of picric acid in soil was monitored in a laboratory study. Furthermore, the presence of picramic acid was for the first time verified in soil samples from a former ammunition plant.
authors.affiliation: Department of Chemistry, Philipps-University Marburg, Germany.
authors.forename: Nicole
authors.initials: N
authors.lastname: Pamme
authors.forename: Klaus
authors.initials: K
authors.lastname: Steinbach
authors.forename: Wolfgang J
authors.initials: WJ
authors.lastname: Ensinger
authors.forename: Torsten C
authors.initials: TC
authors.lastname: Schmidt
mesh_terms: D001274:Atmospheric Pressure; D002853:Chromatography, Liquid / Q000379:methods*; D007202:Indicators and Reagents; D009596:Nitrophenols / Q000032:analysis*; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D007202:Indicators and Reagents; D009596:Nitrophenols