Differential Organic Contaminant Ionization Source Detection and Identification in Environmental Waters by Non‐Targeted Analysis

Here, a methodology employing doped Ag(I) salt as an in situ cationization reagent for efficient ionization of nonpolar molecules within a conventional electrospray ionization source is described. The effectiveness of Ag(I)-mediated ionization is demonstrated using ESI Fourier transform mass spectrometry for the rapid detection and identification of priority pollutant polyaromatic hydrocarbon (PAH) species. In contrast to earlier coordination ESI-MS reports employing silver salts, argentated species are not typically observed for PAH species. Instead, oxidation of the PAH occurs to produce only the [PAH]+· odd-electron molecular parent ion, simplifying spectral analysis. In addition, the method demonstrates linear quantitative performance. The Ag(I) reagent provides quantifiable PAHs (not ordinarily amenable to ESI-MS) from 64 ppb, and suggests the immediate potential for sampling and on-line monitoring of complex, real world, and otherwise intractable environmental samples. Finally, the high mass accuracy of ESI Fourier transform mass spectrometry further allows unequivocal identification of molecular formulas within PAH mixtures.Key words: electrospray ionization, nonpolar, hydrocarbons, polyaromatic, Fourier transform mass spectrometry.

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Animal and vegetable fats and oils. Detection and identification of a volatile organic contaminant by GC/MS

10.3403/02391206 ◽

2001 ◽

Keyword(s):

Fats And Oils ◽

Organic Contaminant ◽

Detection And Identification ◽

Volatile Organic

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Extended Targeted and Non-Targeted Strategies for the Analysis of Marine Toxins in Mussels and Oysters by (LC-HRMS)

Toxins ◽

10.3390/toxins10090375 ◽

2018 ◽

Vol 10 (9) ◽

pp. 375 ◽

Cited By ~ 4

Author(s):

Inès Dom ◽

Ronel Biré ◽

Vincent Hort ◽

Gwenaëlle Lavison-Bompard ◽

Marina Nicolas ◽

...

Keyword(s):

High Resolution Mass Spectrometry ◽

A Priori ◽

Detection Methods ◽

Marine Toxins ◽

Targeted Analysis ◽

Detection And Identification ◽

Recent Approach ◽

Emerging Compounds ◽

Geographical Expansion ◽

Lipophilic Toxins

When considering the geographical expansion of marine toxins, the emergence of new toxins and the associated risk for human health, there is urgent need for versatile and efficient analytical methods that are able to detect a range, as wide as possible, of known or emerging toxins. Current detection methods for marine toxins rely on a priori defined target lists of toxins and are generally inappropriate for the detection and identification of emerging compounds. The authors describe the implementation of a recent approach for the non-targeted analysis of marine toxins in shellfish with a focus on a comprehensive workflow for the acquisition and treatment of the data generated after liquid chromatography coupled with high resolution mass spectrometry (LC-HRMS) analysis. First, the study was carried out in targeted mode to assess the performance of the method for known toxins with an extended range of polarities, including lipophilic toxins (okadaic acid, dinophysistoxins, azaspiracids, pectenotoxins, yessotoxins, cyclic imines, brevetoxins) and domoic acid. The targeted method, assessed for 14 toxins, shows good performance both in mussel and oyster extracts. The non-target potential of the method was then challenged via suspects and without a priori screening by blind analyzing mussel and oyster samples spiked with marine toxins. The data processing was optimized and successfully identified the toxins that were spiked in the blind samples.

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Clustering, methodology, and mechanistic insights into acetate chemical ionization using high-resolution time-of-flight mass spectrometry

Atmospheric Measurement Techniques ◽

10.5194/amt-9-3969-2016 ◽

2016 ◽

Vol 9 (8) ◽

pp. 3969-3986 ◽

Cited By ~ 27

Author(s):

Patrick Brophy ◽

Delphine K. Farmer

Keyword(s):

High Resolution ◽

Atmospheric Pressure ◽

Chemical Ionization ◽

Time Of Flight ◽

Ionization Mass ◽

Resolution Time ◽

Ionization Source ◽

Targeted Analysis ◽

The Impact

Abstract. We present a comprehensive characterization of cluster control and transmission through the Tofwerk atmospheric pressure interface installed on various chemical ionization time-of-flight mass spectrometers using authentic standards. This characterization of the atmospheric pressure interface allows for a detailed investigation of the acetate chemical ionization mechanisms and the impact of controlling these mechanisms on sensitivity, selectivity, and mass spectral ambiguity with the aim of non-targeted analysis. Chemical ionization with acetate reagent ions is controlled by a distribution of reagent ion-neutral clusters that vary with relative humidity and the concentration of the acetic anhydride precursor. Deprotonated carboxylic acids are primarily detected only if sufficient declustering is employed inside the atmospheric pressure interface. The configuration of a high-resolution time-of-flight chemical ionization mass spectrometer (HR-TOF-CIMS) using an acetate chemical ionization source for non-targeted analysis is discussed. Recent approaches and studies characterizing acetate chemical ionization as it applies to the HR-TOF-CIMS are evaluated in light of the work presented herein.

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