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The C–F alkyl structural backbone of per- and polyfluoroalkyl substances makes this class of molecules resistant to heat and degradation, leading to their high persistence and mobility in the environment and bioaccumulation in the tissues of living organisms. In this study, 15 PFAS with an alkyl chain length from C4 to C14, currently monitored by the U.S. Environmental Protection Agency (EPA), were preconcentrated by solid-phase microextraction (SPME) and analyzed by liquid chromatography-tandem mass spectrometry. The adsorption and desorption mechanisms of PFAS onto ion-exchange extraction phases was evaluated to understand the extraction process of PFAS from various environmental matrices under different conditions. This was achieved using two SPME geometries, namely fibers and thin films. The use of thin films resulted in a twofold improvement in extraction efficiency compared to fibers, especially for the short-chain PFAS. Methanol:water (80:20, v/v) was chosen as the optimized desorption solution, with ammonium formate added to minimize carryover. Extraction time profiles for both SPME geometries showed faster equilibration with thin films (30 min) compared to fibers (90–120 min). The linear dynamic range obtained with this method using fibers and thin films ranged from 10 to 5000 ng L 1 and 2.5–5000 ng L 1, respectively, with acceptable accuracy (70–130%) and precision (<15%). LOD ranged within 2.5–10 ng L 1 for fibers and 0.01–0.25 ng L 1 for thin films. Investigating the factors affecting PFAS recovery in complex samples enabled the quantitative assessment of PFAS contamination in various environmental water samples such as seawater, melted snow and biospecimens like human plasma. A 96-SPME holder was used for validation, which is compatible with sampling in 96-well plates and ensures high throughput in the analysis of real samples. The total concentration of PFAS detected in seawater and snow was 51.3 ng L 1 and 16.4 ng L 1, respectively.
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A LC–MS/MS method for the simultaneous determination of 6‐cyanodopamine, 6‐nitrodopamine, 6‐nitrodopa, 6‐nitroadrenaline and 6‐bromodopamine in human plasma and its clinical application in patients with chronic kidney disease
Abstract The aim of this study was to develop a high‐performance liquid chromatography–tandem mass spectrometry method for the determination of 6‐cyanodopamine, 6‐nitrodopamine, 6‐nitrodopa, 6‐nitroadrenaline and 6‐bromodopamine in human plasma samples. Strata‐X 33 μm solid‐phase extraction cartridges were used for the extraction of the catecholamines from human plasma samples. The catecholamines were separated in a 150 × 3 mm Shim‐pack GIST C18‐AQ column with 3 μm particle size, placed in an oven at 40°C and perfused with 82% mobile phase A (acetonitrile–H2O; 90:10, v/v) + 0.4% acetic acid and 18% mobile phase B (deionized H2O) + 0.2% formic acid at a flow rate of 340 μl/min in isocratic mode. The injected volume was 4 μl and the run lasted 4 min. The method was linear from 0.1 to 20 ng/ml and the lower limit of quantification was 0.1 ng/ml for all analytes. The method was applied to evaluate the plasma levels of catecholamines in plasma of patients with chronic kidney disease and allowed the detection for the first time of circulating levels of the novel catecholamines 6‐bromodopamine and 6‐cyanodopamine.
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- Award ID(s):
- 2214877
- PAR ID:
- 10642075
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Biomedical Chromatography
- Volume:
- 38
- Issue:
- 8
- ISSN:
- 0269-3879
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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