Structural Identification of Highly Polar Nontarget Contaminants in Drinking Water by ESI-FAIMS-Q-TOF-MS
Notice bibliographique
Résumé
Drinking water is a complex mixture that contains thousands of naturally occurring and anthropogenic contaminants. Liquid chromatography-mass spectrometry (LC-MS) methods have gained a tremendous popularity in monitoring nonvolatile, highly polar, and thermally labile components in drinking water. It is well recognized, however, that there are difficulties or limitations of LC-MS methods associated with (1) significant resources (time and effort) involved in sample preparation (preconcentration, fractionation, separation), (2) low screening capacity for target contaminants, and (3) insufficient capabilities for structural identification (elucidation) of nontarget contaminants. Consequently, LC-MS methods are mainly used for the detection of target contaminants (compounds identified in drinking water before), seldom for the structural identification of abundant nontarget pollutants (unidentified pollutants in drinking water), and almost never for the structural identification of nontarget components at a trace level. The paper presents a new method of electrospray ionization high field asymmetric waveform ion mobility spectrometry mass spectrometry (ESI-FAIMS-MS), which can detect a large number of water pollutants in a quick and convenient fashion without preconcentration, fractionation, derivatization, or column separation. Most importantly, the method provides structural identification of nontarget contaminants including species present in drinking water at a sub-parts-per-billion concentration level. The identification of previously unknown contaminants was based on mass measurements of investigated ions and their fragments in mass and tandem mass spectrometry. Elemental compositions of these ions, determined by mass measurements, were used to link dissociation patterns of investigated species with their chemical structures. Characterization of nontarget contaminants of chlorine-treated drinking water by ESI-FAIMS-MS has revealed many previously unknown disinfection byproducts. The most intriguing compound, from a group of highly polar hydroxycarboxylic acids discovered in the study, was the most abundant component of drinking water, glycolic acid. Glycolic acid (toxic to kidneys and associated with a moderate maternal toxicity) has never been considered as a drinking water contaminant, despite the fact that it is present in drinking water at a higher concentration (high ppm) than concentrations of highly polar water pollutants that had attracted most attention in the past. The process of structural elucidation of discovered pollutants, including ultratrace contaminants representing a variety of carboxylic acids, will be presented in detail. The structural identification of highly polar contaminants in drinking water presented in the paper is rarely reported in the literature. The key experimental feature of the ESI-FAIMS-MS method is FAIMS separation, which significantly improves the identification capabilities of mass spectrometry.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».