Chemische Charakterisierung und Spurenanalytik
Filtern
Dokumenttyp
- Zeitschriftenartikel (35)
Sprache
- Englisch (35)
Referierte Publikation
- ja (35) (entfernen)
Schlagworte
- ICP-MS (5)
- Immunoassay (5)
- Nanoparticle (4)
- Cell (3)
- LC-MS/MS (3)
- Laser ablation (3)
- Metrology (3)
- Abwasser (2)
- Amperometry (2)
- Cancer (2)
- Diclofenac (2)
- Heart failure (2)
- Imaging (2)
- Magnetic beads (2)
- Mass Spectrometry (2)
- Mass Spectroscopy (2)
- Metabolomics (2)
- Mobile phase (2)
- Nickel (2)
- Purity assessment (2)
- Wastewater (2)
- 6xHis (1)
- ATCUN (1)
- Adsorption (1)
- Affinity chromatography (1)
- Aluminum oxide (1)
- Analytical methods (1)
- Antikörper (1)
- Automation (1)
- Bacterial lysates (1)
- Basic solvent (1)
- Bead injection spectroscopy (1)
- Benz[a]anthracene (BaA) (1)
- Benzo[a]pyrene (BaP) (1)
- Biomarker (1)
- Bioseparation (1)
- Bisphenol A (1)
- Bisphenol-A (1)
- Blood-brain barrier (1)
- CCQM key comparison (1)
- Cardiolipins (1)
- Carrier (1)
- Chromatography (1)
- Chronic kidney disease (1)
- Combustion Ion Chromatography (1)
- Copper (1)
- Cyclic voltammetry (1)
- Cyclization (1)
- Cytoplasm (1)
- D-glucose (1)
- Degradation (1)
- Diastolic dysfunction (1)
- Downstream processing (1)
- EDTAD (1)
- ELISA (1)
- EPR spectroscopy (1)
- Einzelzellanalyse (1)
- Electrochemistry (1)
- Endocrine disruptor (1)
- Endokrine Disruptoren (1)
- Ergot alkaloids (1)
- Escherichia coli (1)
- Ethylenediaminetetraacetic acid (1)
- FTIR spectroscopy (1)
- Fatty acid metabolism (1)
- Fenton (1)
- Fertilizer (1)
- Festphasenextraktion (1)
- Finow Canal (1)
- Folic acid (1)
- Food analysis (1)
- Fow injection analysis (1)
- Gas chromatography (GC) (1)
- Glucose (1)
- HPLC (1)
- HPLC-MS (1)
- HPLC–MS (1)
- HexaHis-Tag (1)
- High pH (1)
- High-resolution mass spectrometry (1)
- His6 (1)
- His8 (1)
- Hormone (1)
- Human serum (1)
- Hydrolysis products (1)
- Hypothalamus (1)
- IMAC purification (1)
- Immunocapture (1)
- Interlaboratory comparison (1)
- Interlaboratory key comparison (1)
- Iron disorders (1)
- Isotope dilution (1)
- Isotope dilution (ID) (1)
- Isotopologue Distribution (1)
- Kläranlage (1)
- Konjugate (1)
- L-alanine (1)
- Lactate (1)
- Lebensmittel (1)
- Legacy pollution (1)
- Lipidomic profile (1)
- Lipidomics (1)
- Lipids (1)
- Liquid chromatography (1)
- Liquid chromatography (LC) (1)
- Liver X receptor (1)
- MALDI-ToF-MS (1)
- MOF (1)
- Magnetic nanocatalyst (1)
- Maillard reaction (1)
- Mass spectrometry (1)
- Mass spectrometry (MS) (1)
- Matrixeffekte (1)
- Melanoidin (1)
- Melanoidine (1)
- Mercury speciation (1)
- Metabolic Flux (1)
- Metabolic stress (1)
- Metalloprotein (1)
- Metformin (1)
- Method development (1)
- Methylmercury (1)
- Microdialysis (1)
- Microparticles (1)
- Mycotoxins (1)
- NMR spectroscopy (1)
- Nickel chelate (1)
- Non-targeted analysis (1)
- Nontarget analysis (1)
- Nuclear receptor (1)
- Oberflächenwasser (1)
- Ochratoxin A (1)
- Organic contaminants (1)
- Peptide (1)
- Peptide analysis (1)
- Peptide losses (1)
- Per- and Polyfluoroalkyl substances (PFAS) (1)
- Pharmazeutika (1)
- Photodegradation (1)
- Photooxidation (1)
- Polishing (1)
- Pollution (1)
- Polycyclic aromatic hydrocarbon (PAH) (1)
- Probenvorbereitung (1)
- Purity (1)
- QC (1)
- Quality control (1)
- R package (1)
- Recombinant protein (1)
- Recovery (1)
- Reference material (1)
- Round robin exercise (1)
- Sample treatment (1)
- Sapphire (1)
- Sensing (1)
- Sewage sludge (1)
- Sewage treatment plant (1)
- Silanization (1)
- Silbernanopartikel (1)
- Solid-phase extraction (1)
- Sonochemical synthesis (1)
- Speroid (1)
- Spheroid (1)
- Stability (1)
- Standardization (1)
- Therapeutic Drug Monitoring (1)
- Toxikologie (1)
- Transformationsprodukte (1)
- Tumor metabolism (1)
- UV Bestrahlung (1)
- Validation (1)
- Validation trial (1)
- Validierung (1)
- Wasser (1)
- Water analysis (1)
- Yerba mate tea (1)
- Zebrafisch (1)
- Zyklisierung (1)
- β-lactam (1)
Organisationseinheit der BAM
- 1.8 Umweltanalytik (35) (entfernen)
Paper des Monats
- ja (1)
The non-steroidal anti-inflammatory drug (NSAID) diclofenac (DCF) is an important environmental contaminant occurring in surface waters all over the world, because, after excretion, it is not adequately removed from wastewater in sewage treatment plants. To be able to monitor this pollutant, highly efficient analytical methods are needed, including immunoassays. In a medical research project, monoclonal antibodies against diclofenac and its metabolites had been produced. Based on this monoclonal anti-DCF antibody, a new indirect competitive enzyme-linked immunosorbent assay (ELISA) was developed and applied for environmental samples. The introduction of a spacer between diclofenac and the carrier protein in the coating conjugate led to higher sensitivity. With a test midpoint of 3 mg L−1 and a measurement range of 1–30 mg L−1, the system is not sensitive enough for direct analysis of surface water. However, this assay is quite robust against matrix influences and can be used for wastewater. Without adjustment of the calibration, organic solvents up to 5%, natural organic matter (NOM) up to 10 mg L−1, humic acids up to 2.5 mg L−1, and salt concentrations up to 6 g L−1 NaCl and 75 mg L−1 CaCl2 are tolerated. The antibody is also stable in a pH range from 3 to 12. Cross-reactivity (CR) of 1% or less was determined for the metabolites 40-hydroxydiclofenac (40-OH-DCF), 5-hydroxydiclofenac (5-OH-DCF), DCF lactam, and other NSAIDs. Relevant cross-reactivity occurred only with an amide derivative of DCF, 6-aminohexanoic acid (DCF-Ahx), aceclofenac (ACF) and DCF methyl ester (DCF-Me) with 150%, 61% and 44%, respectively. These substances, however, have not been found in samples. Only DCF-acyl glucuronide with a cross-reactivity of 57% is of some relevance. For the first time, photodegradation products were tested for cross-reactivity. With the ELISA based on this antibody, water samples were analysed. In sewage treatment plant effluents, concentrations in the range of 1.9–5.2 mg L−1 were determined directly, with recoveries compared to HPLC-MS/MS averaging 136%.
Concentrations in lakes ranged from 3 to 4.4 ng L−1 and were, after pre-concentration, determined with an average recovery of 100%
Solid wastewater-based fertilizers were screened for per- and polyfluoroalkyl substances (PFAS) by the extractable organic fluorine (EOF) sum parameter method. The EOF values for ten sewage sludges from Germany and Switzerland range from 154 to 7209 mg kg−1. For thermal treated sewage sludge and struvite the EOF were lower with values up to 121 mg kg−1. Moreover, the application of PFAS targeted
and suspect screening analysis of selected sewage sludge samples showed that only a small part of the EOF sum parameter values can be explained by the usually screened legacy PFAS. The hitherto unknown part of EOF sum parameter contains also fluorinated pesticides, pharmaceutical and aromatic compounds. Because these partly fluorinated compounds can degrade to (ultra-)short PFAS in wastewater treatment plants they should be considered as significant sources of organic fluorine in the environment. The combined results of sum parameter analysis and suspect screening reveal the need to update current regulations, such as the German fertilizer ordinance, to focus not solely on a few selected PFAS such as perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) but
consider an additional sum parameter approach as a more holistic alternative. Moreover, diffusion gradient in thin-films (DGT) passive samplers were utilized as an alternative simplified extraction method for PFAS in solid wastewater-based fertilizers and subsequently quantified via combustion ion chromatography. However, the DGT method was less sensitive and only comparable to the EOF values
of the fertilizers in samples with >150 mg kg−1, because of different diffusion properties for various PFAS, but also kinetic exchange limitations.
AbstractIn this study, we present a screening method based on molecular absorption spectrometry to study PFAS uptake and fate in plants. To evaluate the suitability of this method we analyzed plant extracts with molecular absorption spectrometry (MAS) as well as liquid chromatography–tandem mass spectrometry (LC–MS/MS) for mass balance studies (w(F)). French bean plants (Phaseolus vulgaris) were grown on soil spiked using eight PFAS substances that vary in chain length and functional group composition. Specifically, these include three short-chained (C4–C5), five long-chained (C7–C10) carboxylic acids, one sulfonic acid and one sulfonic amide moieties. To investigate substance-specific PFAS uptake systematically, PFAS were spiked as single substance spike. Additionally, we studied one mixture of the investigated substances in equal proportions regarding w(F) and four PFAS mixtures of unknown composition. After 6 weeks, the plants were separated into four compartments. We analyzed the four compartments as well as the soil for extractable organically bound fluorine (EOF) by high resolution-continuum source-graphite furnace-molecular absorption spectrometry (HR-CS-GFMAS) as well as for sum of ten target-PFAS by LC–MS/MS. All three short-chained PFAS perfluorobutanoic acid (PFBA), perfluorobutanoic sulfonic acid (PFBS) and perfluoropentanoic acid (PFPeA) were determined in high concentrations mainly in the fruits of the investigated plants while long-chained PFAS perfluorononanoic acid (PFNA) and perfluorodecanoic acid (PFDA) were mainly determined in roots. PFBS was determined in remarkably high concentrations in leaves compartment by both quantification methods. Overall, comprehensive results of single substance spikes were in good agreement for both methods except for a few cases. Hence, two phenomena were identified: for mixed PFAS spikes of unknown composition huge differences between EOF and sum of target PFAS were observed with systematically higher EOF values. Overall, both methods indicate comparable results with MS being more reliable for known PFAS contamination and MAS being more valuable to identify PFAS exposure of unknown composition.
Graphical Abstract
A certain group of mycotoxins, the ergot alkaloids, has caused countless deaths throughout human history. They are found in rye and other cereals and ingesting contaminated foods can cause serious health problems. To identify contaminated food exceeding the legal limits for ergot alkaloids, a portable and cost-effective test system is of great interest to the food industry. Rapid analysis can be achieved by screening for a marker compound, for which we chose ergometrine. We developed a magnetic bead-based immunoassay for ergometrine with amperometric detection in a flow injection system using a handheld potentiostat and a smartphone. With this assay a limit of detection of 3 nM (1 μg/L) was achieved. In spiked rye flour, ergometrine levels from 25 to 250 μg/kg could be quantified. All results could be verified by optical detection. The developed assay offers great promise to meet the demand for on-site ergometrine detection in the food industry.
The environmental fate of the frequently used broad-spectrum β-lactam antibiotic amoxicillin (AMX) is of high concern regarding the potential evolution of antimicrobial resistance (AMR). Moreover, it is known that AMX is prone to hydrolysis, yielding a variety of hydrolysis products (HPs) with yet unknown effects. Studies to identify those HPs and investigate their formation mechanisms have been reported but a long-term study on their stability in real water samples was missing. In this regard, we investigated the hydrolysis of AMX at two concentration levels in four distinct water types under three different storage conditions over two months. Concentrations of AMX and four relevant HPs were monitored by an LC-MS/MS method revealing pronounced differences in the hydrolysis rate of AMX in tap water and mineral water on the one hand (fast) and surface water on the other(slow). In this context, the occurrence, relative intensities, and stability of certain HPs are more dependent on the water type than on the storage condition. As clarified by ICP-MS, the main difference between the water types was the content of the metals copper and zinc which are supposed to catalyze AMX hydrolysis demonstrating an effective method to degrade AMX at ambient conditions.
Immobilized metal affinity chromatography (IMAC) is a widely used technique for purifying polyhistidine-tagged recombinant proteins. However, it often has practical limitations that require complex optimizations and additional steps for purification. In this study, we introduce functionalized corundum particles as a novel, efficient, and economical method for purifying recombinant proteins in a column-free format. The corundum surface is modified with amino silane APTES, followed by EDTA dianhydride, and then loaded with nickel ions. We used the Kaiser test to monitor the modification process and ICP-MS to quantify the metal-binding capacity. To evaluate the system, we used His-tagged protein A/G (PAG) mixed with bovine serum albumin (BSA). The corundum particles exhibited a binding capacity of approximately 3 mg of protein per gram of corundum or 2.4 mg per 1 mL of corundum suspension. We also examined cytoplasm obtained from different E. coli strains as an example of a complex matrix. Varying the imidazole concentration in the loading and washing buffers showed that higher concentrations during loading improved purity. Even with sample volumes as large as one liter, we successfully isolated recombinant proteins down to a concentration of 1 µg/mL. We found higher purity levels with corundum when comparing the corundum material to standard Ni–NTA agarose beads. We successfully purified His6-MBP-mSA2, a fusion protein comprising monomeric streptavidin and maltose-binding protein, from E. coli cytoplasm, demonstrating the method's applicability. We also purified SARS-CoV-2-S-RBD-His8 expressed in human Expi293F cells, confirming its suitability for mammalian cell culture supernatants. The material cost of the nickel-loaded corundum material (without regeneration) is estimated to be less than 30 cents per gram of functionalized support or 10 cents per milligram of isolated protein. Another advantage of this system is the exceptional physical and chemical stability of corundum particles. Overall, we have demonstrated that this novel material offers an efficient, robust, and cost-effective purification platform for His-tagged proteins, even in challenging, complex matrices and large sample volumes with low product concentrations. This method has potential applications in both small laboratories and large-scale industrial settings.
The investigation of metabolic fluxes and metabolite distributions within cells by means of tracer molecules is a valuable tool to unravel the complexity of biological systems. Technological advances in mass spectrometry (MS) technology such as atmospheric pressure chemical ionization (APCI) coupled with high resolution (HR), not only allows for highly sensitive analyses but also broadens the usefulness of tracer‐based experiments, as interesting signals can be annotated de novo when not yet present in a compound library. However, several effects in the APCI ion source, i.e., fragmentation and rearrangement, lead to superimposed mass isotopologue distributions (MID) within the mass spectra, which need to be corrected during data evaluation as they will impair enrichment calculation otherwise. Here, we present and evaluate a novel software tool to automatically perform such corrections. We discuss the different effects, explain the implemented
algorithm, and show its application on several experimental datasets. This adjustable tool is available as an R package from CRAN.
Towards Unbiased Evaluation of Ionization Performance in LC-HRMS Metabolomics Method Development
(2022)
As metabolomics increasingly finds its way from basic science into applied and regulatory environments, analytical demands on nontargeted mass spectrometric detection methods continue to rise. In addition to improved chemical comprehensiveness, current developments aim at enhanced robustness and repeatability to allow long-term, inter-study, and meta-analyses. Comprehensive metabolomics relies on electrospray ionization (ESI) as the most versatile ionization technique, and recent liquid chromatography-high resolution mass spectrometry (LC-HRMS) instrumentation continues to overcome technical limitations that have hindered the adoption of ESI for applications in the past. Still, developing and standardizing nontargeted ESI methods and instrumental setups remains costly in terms of time and required chemicals, as large panels of metabolite standards are needed to reflect biochemical diversity. In this paper, we investigated in how far a nontargeted pilot experiment, consisting only of a few measurements of a test sample dilution series and comprehensive statistical analysis, can replace conventional targeted evaluation procedures. To examine this potential, two instrumental ESI ion source setups were compared, reflecting a common scenario in practical method development. Two types of feature evaluations were performed, (a) summary statistics solely involving feature intensity values, and (b) analyses additionally including chemical interpretation.
Results were compared in detail to a targeted evaluation of a large metabolite standard panel. We reflect on the advantages and shortcomings of both strategies in the context of current harmonization initiatives in the metabolomics field.
Nebivolol (NEB), a β-blocker frequently used to treat cardiovascular diseases, has been widely detected in aquatic environments, and can be degraded under exposure to UV radiation, leading to the formation of certain transformation products (UV-TPs). Thus, the toxic effects of NEB and its UV-TPs on aquatic organisms are of great importance for aquatic ecosystems. In the present study, the degradation pathway of NEB under UV radiation was investigated. Subsequently, zebrafish embryos/larvae were used to assess the median lethal concentration (LC50) of NEB, and to clarify the sub-lethal effects of NEB and its UV-TPs for the first time. It was found that UV radiation could reduce the toxic effects of NEB on the early development of zebrafish. Transcriptomic analysis identified the top 20 enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways in zebrafish larvae exposed to NEB, most of which were associated with the antioxidant, nervous, and immune systems. The number of differentially expressed genes (DEGs) in the pathways were reduced after UV radiation. Furthermore, the analysis of protein biomarkers, including CAT and GST (antioxidant response), AChE and ACh (neurotoxicity), CRP and LYS (immune response), revealed that NEB exposure reduced the activity of these biomarkers, whereas UV radiation could alleviate the effects. The present study provides initial insights into the mechanisms underlying toxic effects of NEB and the detoxification effects of UV radiation on the early development of zebrafish. It highlights the necessity of considering the toxicity of UV-TPs when evaluating the toxicity of emerging pollutants in aquatic systems.
Cardiolipin (CL) is a major cardiac mitochondrial phospholipid maintaining regular mitochondrial morphology and function in cardiomyocytes. Cardiac CL production includes ist biosynthesis and a CL-remodeling process. Here we studied the impact of CL-biosynthesis and the enzyme Cardiolipin Synthase (CLS) on cardiac function.
CLS and cardiac CL-species were significantly downregulated in cardiomyocytes following catecholamine-induced cardiac damage in mice, accompanied by increased oxygen consumption rates, signs of oxidative stress and mitochondrial uncoupling. RNAi-mediated cardiomyocyte-specific knockdown of CLS in Drosophila melanogaster resulted in marked cardiac dilatation, severe impairment of systolic performance and slower diastolic filling velocity assessed by fluorescence-based heart imaging. Finally, we showed that CL72:8 is significantly decreased in cardiac samples from patients with heart failure with reduced ejection fraction (HFrEF). In summary, we identified CLS as a regulator of cardiac function. Considering the cardiac depletion of CL-species in HFrEF, pharmacological targeting of CLS may be a promising therapeutic approach.zeige mehrzeige weniger