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Chemical structures of two gadolinium chelates typically used in MRI, (a) Magnevist with linear and (b) Gadovist with macrocyclic polyaminopolycarboxylic acid ligands.
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... from the paramagnetic elements manganese and iron, the lanthanide gadolinium, with its seven unpaired electrons in the outer electron shell, is one of the metals most commonly used in MRI contrast agents. Because of its intrinsic toxicity, however, gadolinium cannot be used in the free ionic form (Gd 3+ ), but only in the form of its water-soluble chelate complexes ( Figure 1). In particular, the derivates of diethylenetriaminepentaacetic acid (DTPA) have proved useful as MRI contrast-enhancing agents. ...
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Imaging non-invasively into the human body is currently limited by cost (MRI and CT scan), image resolution (ultrasound), exposure to ionising radiation (CT scan and X-ray), and the requirement for exogenous contrast agents (CT scan and PET scan). Optical imaging has the potential to overcome all these issues but is currently limited by imaging dep...
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Цель. На современном этапе развития медицины использование рентгеноконтрастных препаратов имеет тенденцию к постоянному росту и составляет ежегодно более 60 млн доз рентгеноконтрастных соеди-нений (РКС) ежегодно. Целью исследования было изучение нежелательных реакций (НР), возникающих при применении РКС у пациентов, проживающих на территори...
Citations
... However recently, Okabayashi et al. were able to separate up to six different GBCAs in 13.3 min using a HILIC method that was based on an aqueous mobile phase only (Okabayashi et al., 2021). Purely aqueous conditions, such as those used in ion-exchange chromatography (IC), might be a favorable alternative to separate the polar to ionic Gd species (Pfundstein et al., 2011;Telgmann et al., 2012a). In general, organic solvent-free approaches address an important aspect of Green Analytical Chemistry (Anastas, 1999). ...
Gadolinium-based contrast agents (GBCAs) are frequently used for magnetic resonance imaging to improve image contrast. These inert complexes are excreted unmetabolized from the human body and pass through wastewater treatment plants almost unaffected, leading to a significant release of anthropogenic Gd into the environment. However, long-term ecotoxicological effects of GBCAs are mainly unknown and thus powerful methods of speciation analysis are required to monitor their distribution and fate in aquatic systems. In this work, a rapid and efficient monitoring method was developed utilizing a fully automated single platform system for total metal analysis and syringe-driven chromatography in combination with inductively coupled plasma-mass spectrometry (ICP-MS). An anion-exchange chromatography (IC) method was developed and applied to achieve a rapid separation and sensitive detection of the five complexes Gd-HP-DO3A, Gd-BT-DO3A, Gd-DOTA, Gd-DTPA, and Gd-BOPTA that are commonly administered in the European Union. Furthermore, the use of an automated inline-dilution function allowed a fast-external calibration from single stock standards. A chromatographic run time of less than 2 min and species-specific detection limits between 11 and 19 pmol L⁻¹ on a quadrupole ICP-MS proved to be competitive compared to previously published methods, but without the use of aerosol drying and/or sector field ICP-MS to enhance sensitivity. The automated IC-ICP-MS method was applied for quantitative GBCA monitoring in a multitude of surface water samples that were obtained in the German state of North Rhine-Westphalia. The complexes Gd-HP-DO3A, Gd-BT-DO3A, and Gd-DOTA, were detected and quantified. In addition, the occurrence of an unidentified Gd species was observed for one of the sampled river systems.
... Moreover, size exclusion chromatography (SEC) was used with ICP-MS to separate free Gd 3+ from Gd complexes and Gd adducts; however, the size differences between the individual Gd chelates are too small for effective SEC separation [133,134]. Ion chromatography (IC) [131,135], time-resolved luminescence (TRL) detector [136], and direct fluorescence [137] are also utilized for the separation of Gd species. Künnemeyer et al. [138] indicated a high separation efficiency of hydrophilic interaction chromatography (HILIC) for ionic and polar compounds by the determination of contrast agents in blood plasma using HILIC hyphenated to electrospray ionization mass spectrometry (ESI-MS). ...
The Phlegrean Fields are located in southern Italy and the latest volcanic eruption in this area goes back to 1538 CE. In the last decades, the bradysismic crises were sometimes followed by evacuation orders from the authorities to manage an emergency. On the other hand, the study area is highly populated and urbanization, industries together with agricultural practices may pose a threat to the ecosystem and human health. The main objective of this thesis is to use some recently developed data treatment approaches (i.e. compositional data analysis and spatial analysis) for highlighting the dominant processes controlling geochemical composition of different environmental compartments.
... Moreover, size exclusion chromatography (SEC) was used with ICP-MS to separate free Gd 3+ from Gd complexes and Gd adducts; however, the size differences between the individual Gd chelates are too small for effective SEC separation [133,134]. Ion chromatography (IC) [131,135], time-resolved luminescence (TRL) detector [136], and direct fluorescence [137] are also utilized for the separation of Gd species. Künnemeyer et al. [138] indicated a high separation efficiency of hydrophilic interaction chromatography (HILIC) for ionic and polar compounds by the determination of contrast agents in blood plasma using HILIC hyphenated to electrospray ionization mass spectrometry (ESI-MS). ...
As a result of high doses of paramagnetic gadolinium (Gd) chelates administered in magnetic resonance imaging (MRI) exams, their unmetabolized excretion, and insufficient removal in wastewater treatment plants (WWTPs), large amounts of anthropogenic Gd (Gdanth) are released into surface water. The upward trend of gadolinium-based contrast agent (Gd-CA) administrations is expected to continue growing and consequently higher and higher anthropogenic Gd concentrations are annually recorded in water resources, which can pose a great threat to aquatic organisms and human beings. In addition, the feasibility of Gd retention in patients administered with Gd-CAs repeatedly, and even potentially fatal diseases, including nephrogenic systemic fibrosis (NSF), due to trace amounts of Gd have recently arisen severe health concerns. Thus, there is a need to investigate probable adverse health effects of currently marketed Gd-CAs meticulously and to modify the actual approach in using Gd contrast media in daily practice in order to minimize unknown possible health risks. Furthermore, the employment of enhanced wastewater treatment processes that are capable of removing the stable contrast agents, and the evaluation of the ecotoxicity of Gd chelates and human exposure to these emerging contaminants through dermal and ingestion pathways deserve more attention. On the other hand, point source releases of anthropogenic Gd into the aquatic environment presents the opportunity to assess surface water—groundwater interactions and trace the fate of wastewater plume as a proxy for the potential presence of other microcontaminants associated with treated wastewater in freshwater and marine systems.
... Therefore, it is necessary to develop highly sensitive speciation analysis methods. Methods based on ion chromatography (IC), high performance liquid chromatography (HPLC), and size exclusion chromatography (SEC) have been developed for the chromatographic separation of gadolinium-based contrast agents [17][18][19]. In 2008, Künnemeyer et al. demonstrated the separation of commonly applied contrast agents using hydrophilic interaction liquid chromatography (HILIC) hyphenated to electrospray ionization mass spectrometry (ESI-MS) [20]. ...
In recent decades, a significant amount of anthropogenic gadolinium has been released into the environment as a result of the broad application of contrast agents for magnetic resonance imaging (MRI). Since this anthropogenic gadolinium anomaly has also been detected in drinking water, it has become necessary to investigate the possible effect of drinking water purification on these highly polar microcontaminats. Therefore, a novel highly sensitive method for speciation analysis of gadolinium is presented. For that purpose, the hyphenation of hydrophilic interaction liquid chromatography (HILIC) and inductively coupled plasma-mass spectrometry (ICP-MS) was employed. In order to enhance the detection power, sample introduction was carried out by ultrasonic nebulization. In combination with a novel HILIC method using a diol-based stationary phase, it was possible to achieve superior limits of detection for frequently applied gadolinium-based contrast agents below 20 pmol/L. With this method, the contrast agents Gd-DTPA, Gd-DOTA and Gd-BT-DO3A were determined in concentrations up to 159 pmol/L in samples from several waterworks in a densely populated region of Germany alongside the river Ruhr as well as from a waterworks near a catchment lake. Thereby, the direct impact of anthropogenic gadolinium species being present in the surface water on the amount of anthropogenic gadolinium in drinking water was shown. There was no evidence for the degradation of contrast agents, the release of Gd3+ or the presence of further Gd species.
