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1.
Electrophoresis ; 2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37946621

RESUMO

In this study, we investigated the uptake and metabolization of four drugs (plus the associated prodrugs) from the sartan family by eight edible plants. Growing the plants hydroponically in a medium containing the respective drug, more than 40 phases I and II metabolites derived from the four sartan drugs could be tentatively identified. To demonstrate the suitability of the proposed analytical approach for actual environmental samples, garden cress (Lepidium sativum) selected as a model plant was grown in water drawn from the effluent of two local wastewater treatment plants. Thereby, three of the sartans, namely, olmesartan, candesartan, and valsartan, could be found in the plant extracts at concentrations of 3.1, 10.4, and 14.4 ng g-1 , respectively. Additionally, for candesartan and valsartan, a glycosylated transformation product could be detected. In order to extend the present (targeted) workflow also toward the analysis of unknown transformation products (i.e., those not listed in the custom-made database used for this research), a nontargeted approach for the analysis of plant extracts with respect to the presence of drug-related metabolites was developed. Comparison of the targeted and the nontargeted workflows led to the finding of two additional, so far unidentified, transformation products originating from azilsartan.

2.
Isotopes Environ Health Stud ; 54(3): 274-287, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29166773

RESUMO

Tritium (3H) is an essential tracer of the Earth's water cycle; yet widespread adoption of tritium in hydrologic studies remains a challenge because of analytical barriers to quantification and detection of 3H by electrolytic pre-concentration. Here, we propose a simple tritium electrolytic enrichment system based on the use of solid polymer electrolyte membranes (PEMs) that can be used to enrich 3H in 250-3000 mL environmental water samples to a 10-mL final volume. The IAEA PEM-3H system reported here can produce high enrichment factors (>70-fold) and, importantly, removes some of the deterrents to conventional 3H enrichments methods, including the use of toxic electrolysis and neutralization chemicals, spike standards, a complex electrolysis apparatus that requires extensive cooling and temperature controls, and improves precision by eliminating the need for tracking recovery gravimetrics. Preliminary results with varying operating conditions show 3H enrichments to 70-fold and higher are feasible, spanning a wide range of tritium activities from 5 to 150 TU with a precision of ∼4.5 %. Further work is needed to quantify inter-sample memory and to establish lower 3H detection limits. The IAEA PEM-3H system is open source, with 3-D CAD and design files made freely available for adoption and improvement by others.


Assuntos
Eletrólise/métodos , Eletrólitos/química , Membranas Artificiais , Trítio/química , Polímeros/química
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