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The normal functioning of the endocrine system of humans and animals can be harmed by chemical compounds when they are present above a certain threshold in the environment. These compounds are referred to as endocrine disrupting compounds (EDCs). (Tyler et al., 2005, de Jesus Gaffney et al., 2014, Bieman, Blüher and Isermann, 2021). 
According to Sonnenschein and Soto (1998), four abilities can make EDCs hazardous: "(1) mimic the effect of endogenous hormones, (2) antagonize the effect of endogenous hormones, (3) disrupt the synthesis and metabolism of endogenous hormones, and (4) disrupt the synthesis and metabolism of hormone receptors.".
Among all EDCs, some of the most potent are estrogenic compounds (e-EDCs), so-called because they are able to mimic the natural and endogenous hormone called estradiol (E2) (Arcand-Hoy, Nimrod and Benson, 1997). There are three main types of e-EDCs, the synthetic (eg. pharmaceuticals, pesticides, surfactants, etc...) and the naturally produced which are either endogenous hormones from humans and animals (e.g. E2) or from plants (phytoestrogens) (Hamid and Eskicioglu, 2012 citing Caliman and Gavrilescu, 2009 and Burkhardt-Holm, 2010). e-EDCs are now ubiquitous in the environment and some of these compounds can be persistent. The major concern is probably the fate of e-EDCs in water as the aquatic environment represents the "ultimate sink for most chemicals" (Sumpter, 1998). e-EDCs can end up in the aquatic environment through three different pathways: the domestic effluents of wastewater treatment plants (WWTPs), the industrial effluents, and the agricultural waste products (Arcand-Hoy, Nimrod and Benson, 1997, Campbell et al., 2006).
Along with E2, highly important are also estrone (E1) and ethinyl estradiol (EE2). Their use includes oral contraceptive pills, hormone replacement therapy (HRT) and growth promoters in livestock production. The natural (endogenous hormones E1 and E2) and synthetic estrogens (e.g EE2) are excreted through urine and feces. These compounds have been demonstrated to contribute to the estrogenic activity of sewage or wastewater treatment plant (WWTP) effluents that are eventually discharged in the aquatic environment (Huang and Sedlak, 2001, Sumpter and Jobling, 2013, Valdés et al., 2015). The occurrence of such contaminants in water could further cause environmental hazards such as male fish feminization even when present at the nanogram per liter level (Purdom et al., 1994, Parrott and Blunt, 2004). Moreover, as these contaminants are persistent, it is suspected that they can bioaccumulate in aquatic organisms and ultimately be consumed by humans through the food chain route (Bilal, Barceló and Iqbal, 2021).
Accordingly, the E1, E2 and EE2 were included in the EU Water Framework Directive Watch List (WL) published in 2015. The EU WL established a list of substances that may pose a risk for the aquatic environment, but for which monitoring data are lacking to assess the actual risk. The proposed maximum detection limits (LODs) in this WL are of 0.4 ng/L for E1 and E2 and of 0.035 ng/L for EE2 (EC Decision 2015/495).
Seeing the extremely low sensitivity (i.e. ultra-trace level) required to meet the WL requirements, there is the need for performant, robust, selective and sensitive analytical methods. In this study, the feasibility of new methods using sorptive extraction, miniaturized techniques, derivatization and gas chromatography (GC) coupled with mass spectrometry (MS) or tandem mass spectrometry (MS/MS) was investigated. Le fonctionnement normal du système endocrinien des humains et des animaux peut être 
perturbé par des composés chimiques lorsqu'ils sont présents dans l'environnement au-delà d'un 
certain seuil. Ces composés sont appelés perturbateurs endocriniens (PEs). (Tyler et al., 2005, 
de Jesus Gaffney et al., 2014, Bieman, Blüher et Isermann, 2021). 
Selon Sonnenschein et Soto (1998), quatre capacités peuvent rendre ces PEs dangereux : " (1) 
imiter l'effet des hormones endogènes, (2) antagoniser l'effet des hormones endogènes, (3) 
perturber la synthèse et le métabolisme des hormones endogènes, et (4) perturber la synthèse 
et le métabolisme des récepteurs hormonaux ".
Parmi tous les PEs, certains des plus puissants sont les composés œstrogéniques (PE-e), appelés 
ainsi car ils sont capables d'imiter l'hormone naturelle et endogène appelée œstradiol (E2) 
(Arcand-Hoy, Nimrod et Benson, 1997). Il existe trois principaux types de PE-e, les 
synthétiques (par exemple, les produits pharmaceutiques, les pesticides, les agents de surface, 
etc.) et les produits naturels qui sont soit des hormones endogènes provenant des humains et 
des animaux (par exemple, E2) ou soit provenant des plantes (phytoestrogènes) (Hamid et 
Eskicioglu, 2012 citant Caliman et Gavrilescu, 2009 et Burkhardt-Holm, 2010). Les PE-e sont 
maintenant omniprésents dans l'environnement et certains de ces composés peuvent être 
persistants. La principale préoccupation est probablement le devenir des PE-e dans l'eau, car 
l'environnement aquatique représente le " puit ultime pour la plupart des produits chimiques " 
(Sumpter, 1998). Les PE-e peuvent se retrouver dans l'environnement aquatique par trois voies 
différentes : les effluents domestiques des stations d'épuration (STEP), les effluents industriels 
et les déchets agricoles (Arcand-Hoy, Nimrod et Benson, 1997, Campbell et al., 2006).
Outre E2, l'estrone (E1) et l'éthinylestradiol (EE2) sont également très importants. Leur 
utilisation comprend les pilules contraceptives orales, la thérapie de remplacement hormonal
(TRH) et les stimulateurs de croissance dans la production animale. Les œstrogènes naturels 
(hormones endogènes E1 et E2) et synthétiques (par exemple EE2) sont excrétés dans l'urine 
et les fèces. Il a été démontré que ces composés contribuent à l'activité œstrogénique des eaux 
usées ou des effluents des stations d'épuration des eaux usées (STEP) qui sont finalement 
déversés dans l'environnement aquatique (Huang et Sedlak, 2001, Sumpter et Jobling, 2013, 
Valdés et al., 2015). La présence de ces contaminants dans l'eau pourrait en outre provoquer 
des risques environnementaux tels que la féminisation des poissons mâles, même lorsqu'ils sont 
présents au niveau du nanogramme par litre (Purdom et al., 1994, Parrott et Blunt, 2004). De 
plus, comme ces contaminants sont persistants, on soupçonne qu'ils peuvent se bioaccumuler 
dans les organismes aquatiques et finalement être consommés par les humains à travers la 
chaîne alimentaire (Bilal, Barceló et Iqbal, 2021).
En conséquence, les E1, E2 et EE2 ont été inclus dans la liste de surveillance de la directive cadre sur l'eau de l'UE (WL) publiée en 2015. La WL de l'UE a établi une liste de substances 
qui peuvent présenter un risque pour l'environnement aquatique, mais pour lesquelles les 
données de surveillance font défaut pour évaluer le risque réel. Les limites maximales de 
détection (LOD) proposées dans cette WL sont de 0,4 ng/L pour E1 et E2 et de 0,035 ng/L pour 
EE2 (Décision CE 2015/495).
Au vu de la sensibilité extrêmement faible (c'est-à-dire au niveau de l'ultra-trace) requise pour 
répondre aux exigences de la WL, il est nécessaire de disposer de méthodes analytiques 
performantes, robustes, sélectives et sensibles. Dans cette étude, la faisabilité de nouvelles 
méthodes utilisant l'extraction sorptive, les techniques miniaturisées, la dérivatization et la 
chromatographie en phase gazeuse (GC) couplée à la spectrométrie de masse (MS) ou à la 
spectrométrie de masse en tandem (MS/MS) a été étudiée.

Estrogens, water, contaminants analyzis, mass spectrometry, gas chromatography --- Physique, chimie, mathématiques & sciences de la terre > Chimie

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This collection highlights gemstone identification and analysis using spectroscopic techniques. It also includes the exciting applications of artificial intelligence and machine learning technologies that are being developed and used to enhance the efficiency of identification and analysis techniques.

Gemology --- Artificial intelligence --- Spectrum analysis. --- Spectrum analysis, spectrochemistry, mass spectrometry. --- SCIENCE / Spectroscopy & Spectrum Analysis. --- Data processing. --- Industrial applications.

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As the population is becoming older, osteoporosis is more and more important worldwide. It affects 200 
million women and costs enormously to society. Also, the treatment is not always effective, and the 
compliance is low. Adverse effects are really important and the absorption of molecules for 
bisphosphonates, which is the most common therapy, is less than 2%. A follow-up of the treatment is thus 
necessary, as it is not correctly taken. This follow-up is based on bone formation and resorption markers. 
In the present work, the focus will be realised on ß-CTX, a degradation product of type 1 collagen. 
Immunoassays analysing the concentration of ß-CTX in biological samples gave different concentrations 
when the analysis was realised on a same sample. The work here was part of a larger one which consisted 
of creating a commutable standard to harmonize every immunoassay. The project was separated in 
different parts. The first one was the isolation of ß-CTX by liquid chromatography, followed by a 
characterization by mass spectrometry. Indeed, the structure was still unknown. Finally, the creation of an 
internal standard and a commutable product was planned. This work describes the isolation part. 
The isolation was an important part of the work. Indeed, the more the sample was separated, the more ß CTX was pure and the more the characterization was realised easily. Different parameters were tested, such 
as the addition of ammonium formate, formic acid and DMSO in phases. These were really efficient for the 
separation. Also, the gradient was optimized, as it was elongated to allow a better separation of the peaks. 
Finally, the injection solvent was modified, with the removing of the acetonitrile and the addition of DMSO. 
All these modifications of parameters on the method are described in detail. They lead to a good 
separation of the peaks and it was thus possible to pass to the second part of the project which was the 
characterization.

Osteoporosis --- B-CTX --- High pressure liquid chromatogrpahy --- HPLC --- mass spectrometry --- Sciences de la santé humaine > Multidisciplinaire, généralités & autres

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This volume presents updated methods and new developments in the field of mass spectrometry imaging. Chapters guide readers through four parts covering imaging, software, data analysis, new instrumentation, and new methodological approaches. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and cutting-edge, Mass Spectrometry Imaging of Small Molecules aims to be a useful practical guide to researchers to help further their study in this field. .

Mass spectroscopy. --- Biomolecules. --- Mass Spectrometry. --- Small Molecules. --- Biological molecules --- Molecules --- Molecular biology --- Mass spectra --- Mass spectrograph --- Mass spectroscopy --- Mass spectrum analysis --- Mass (Physics) --- Nuclear spectroscopy --- Spectrum analysis

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This open access book covers recent advances in experiments using the ultra-cold, very weakly perturbing superfluid environment provided by helium nanodroplets for high resolution spectroscopic, structural and dynamic studies of molecules and synthetic clusters. The recent infra-red, UV-Vis studies of radicals, molecules, clusters, ions and biomolecules, as well as laser dynamical and laser orientational studies, are reviewed. The Coulomb explosion studies of the uniquely quantum structures of small helium clusters, X-ray imaging of large droplets and electron diffraction of embedded molecules are also described. Particular emphasis is given to the synthesis and detection of new species by mass spectrometry and deposition electron microscopy.

Nuclear physics --- Low temperature physics --- Spectrum analysis, spectrochemistry, mass spectrometry --- Microscopic superfluidity --- X-ray imaging --- Spectroscopy of biomolecules --- Spectroscopic matrices --- Vibronic spectroscopy --- Rovibronic spectroscopy