Chemie und Prozesstechnik
Filtern
Dokumenttyp
- Zeitschriftenartikel (126) (entfernen)
Schlagworte
- ICP-MS (21)
- Laser ablation (15)
- Nanoparticle (12)
- Traceability (10)
- Imaging (8)
- PFAS (7)
- Cell (6)
- Metrology (6)
- Copper (5)
- Fluorescence (5)
- LA-ICP-MS (5)
- Uncertainty (5)
- Absolute isotope ratio (4)
- Calibration (4)
- HR-CS-GFMAS (4)
- Immunohistochemistry (4)
- Isotope dilution (4)
- Magnetic resonance imaging (4)
- Mass spectrometry (4)
- Measurement uncertainty (4)
- Brain (3)
- Cement (3)
- Extractable organically bound fluorine (EOF) (3)
- High resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) (3)
- Human serum (3)
- Isotope ratio (3)
- Isotope ratios (3)
- LC-MS/MS (3)
- MC-ICP-MS (3)
- Nanoparticles (3)
- Reference material (3)
- Sulfur (3)
- Affinity chromatography (2)
- Analytical Chemistry (2)
- Bioconjugation (2)
- Bioimaging (2)
- Cancer (2)
- Cells (2)
- Comparability (2)
- Contrast agent (2)
- Delta scale (2)
- Delta value (2)
- Diatoms (2)
- Editorial (2)
- Environmental speciation (2)
- Fluorine (2)
- Gadolinium (2)
- General Earth and Planetary Sciences (2)
- ICP-ToF-MS (2)
- Interlaboratory comparison (2)
- Iron (2)
- Isotope dilution mass spectrometry (2)
- Isotope reference material (2)
- Isotopic fractionation (2)
- Lithium (2)
- MRI (2)
- Mercury (2)
- Metals (2)
- Metrology in chemistry (2)
- Molar mass (2)
- Nanomaterials (2)
- Nickel (2)
- Peptide (2)
- Peptide library (2)
- Per- and polyfluorinated alkyl substances (PFASs) (2)
- Purity (2)
- Quantification (2)
- SI (2)
- SI traceability (2)
- SPM (2)
- Single particle ICP-MS (2)
- Solid-liquid extraction (2)
- Sr isotopes (2)
- Triple isotope fractionation (2)
- 150th anniversary (1)
- 3D ultrastructural analysis (1)
- 6xHis (1)
- AAS (1)
- ABC (1)
- AF4 (1)
- ATCUN (1)
- Absorption spectrometry (1)
- Adsorbable organically bound fluorine (AOF) (1)
- Adsorption (1)
- Affinity (1)
- Affinity extraction (1)
- Alanine scan (1)
- Albumin (1)
- Algorithms (1)
- Aluminum oxide (1)
- Alzheimer’s disease (1)
- Amyloid-beta (1)
- Analysis (1)
- Analytical chemistry (1)
- Analytical sciences (1)
- Anemia (1)
- Antifouling biocides (1)
- Antifouling-Biozide (1)
- Antikensammlung Berlin (1)
- App (1)
- Argon (1)
- Array (1)
- Arsenite (1)
- Atomic Absorption Spectrometry (1)
- Atomic Force Microscopy (1)
- Atomic absorption spectrometry (1)
- Atomic weight (1)
- Automated system (1)
- Avogadro constant (1)
- BAM (1)
- Bacterial lysates (1)
- Binding molecule (1)
- Bioapatite (1)
- Biodiesel fuel (1)
- Biogenic carbonates (1)
- Biological boron recycling (1)
- Bioseparation (1)
- Boron isotope (1)
- Boron isotope fractionation (1)
- Boron isotopic composition (1)
- Brassica napus (1)
- Bundesanstalt für Materialforschung und -prüfung (1)
- Böden (1)
- CCQM (1)
- CE/MC-ICP-MS (1)
- CIC (1)
- CRM (1)
- Calcification (1)
- Calcium (1)
- Calcium monofluoride (1)
- Capillary electrophoresis-mass spectrometry (1)
- Carbodiimide crosslinking (1)
- Carrier (1)
- Cconventional method (1)
- Cellular trafficking (1)
- Central Taurus (1)
- Certification (1)
- Chelate (1)
- Chemometrie (1)
- Chemometrik (1)
- Chenopodium album (1)
- Chicken antibodies (1)
- Chromatography (1)
- Ciaaw.org (1)
- Classical primary measurement method (CPM) (1)
- Cleaning (1)
- Climate (1)
- Cluster (1)
- Collection (1)
- Combinatorial chemistry (1)
- Combustion ion chromatography (1)
- Combustion ion chromatography (CIC) (1)
- Complementary MS (1)
- Comsumer good samples (1)
- Confocal laser scanning microscopy (1)
- Conventional isotope ratio (1)
- Corophium volutator (1)
- Cryo-soft X-ray tomography (1)
- Cytoplasm (1)
- Cytoplasmic remodeling (1)
- Data processing (1)
- Degradation (1)
- Delta isotope standard (1)
- Dendritic polyglycerol sulfate (1)
- Diagenesis (1)
- Diagnostics (1)
- Diatomeenanalytik (1)
- Diffusion (1)
- Digestion (1)
- Dip-stick assay (1)
- Direct metal assay (1)
- Dissolution (1)
- Docking (1)
- Downstream processing (1)
- Dyes/pigments (1)
- EDTAD (1)
- ELISA (1)
- EPMA (1)
- Early Earth (1)
- Ecotoxicity (1)
- Ecotoxicological Testing (1)
- Ecotoxicology testing (1)
- Einzelzellanalyse (1)
- Elemental analysis (1)
- Elemental composition (1)
- Elemental fingerprints (1)
- Environment (1)
- Environmental pollution monitoring (1)
- Escherichia coli (1)
- Ethylenediaminetetraacetic acid (1)
- Exposure (1)
- Extracellular matrix (1)
- Extrahierbar organisch gebundenes Fluor (EOF) (1)
- Fe nanoparticles metabolism (1)
- Fertilizer (1)
- Finow Canal (1)
- Fluor (1)
- Fluorescence label (1)
- Fluorination (1)
- Fluorophilic interactions (1)
- GD-MS (1)
- GD-OES (1)
- GDMS (1)
- GF-MAS (1)
- Gadolinium-based contrast agents (GBCAs) (1)
- Geochemistry (1)
- Geochemistry and Petrology (1)
- Geological material (1)
- Geophysics (1)
- Glycosaminoglycan (1)
- Graphite furnace (1)
- Greek curse tablets (1)
- Group profile (1)
- HF free Digestion (1)
- HPLC-ICP-MS (1)
- HR-CS-MAS (1)
- Hafnium (1)
- Heat flow (1)
- HexaHis-Tag (1)
- High pH (1)
- High pressure experiments (1)
- High-fired gypsum mortar (1)
- High-purity elements (1)
- High-resolution continuum source graphite furnace atomic absorption spectrometry (1)
- His6 (1)
- His8 (1)
- Hot-pressing (1)
- Hydrated silicate melts (1)
- Hydrodynamic chromatography (HDC) (1)
- Hydrogen (1)
- Hydrolysis products (1)
- Hydrothermal fluid (1)
- Hyphenated (1)
- ICP-MS/MS (1)
- ICP-TOF-MS (1)
- ICP-TOFMS (1)
- IDMS (1)
- ILC (1)
- IMAC purification (1)
- IgY (1)
- Iinductively coupled plasma mass spectrometry (1)
- Immunoaffinity extraction (1)
- Immunocapture (1)
- Immunofluorescence (1)
- Immunology (1)
- Impurity assessment (1)
- In situ (1)
- In vitro (1)
- In-house calibration solution (1)
- Industrielle Analytik (1)
- Inflammation (1)
- Inorganic chemical analysis (1)
- Instrumental isotope fractionation (1)
- Iposomes (1)
- Iridium (1)
- Iron nanoparticles (1)
- Iron oxide (1)
- Isotope (1)
- Isotope Dilution (1)
- Isotope amount ratio (1)
- Isotope delta (1)
- Isotope delta value (1)
- Isotope fractionation (1)
- Isotopes (1)
- Isotopic analysis (1)
- Isotopic dilution (1)
- Jahrestag (1)
- Kapillarelektrophorese-Massenspektrometrie (1)
- Kidney (1)
- Kilogram (1)
- Komplementäre Massenspektrometrie (1)
- Kristallolgraphie (1)
- LA-(MC-)ICP-MS (1)
- LA/ICP-MS Imaging (1)
- LSVEC (1)
- Lab-on-a-chip (1)
- Labeling (1)
- Lanthanide (1)
- Laser (1)
- Laser Ablation (1)
- Laser Ablation/Imaging (1)
- Laser ablation inductively coupled plasma–mass spectrometry imaging (LA-ICP-MSI) (1)
- Lead (1)
- Lead isotope composition (1)
- Lead isotope ratios (1)
- Lead isotope variations (1)
- Lead isotopes (1)
- Legacy pollution (1)
- Life sciences (1)
- Limit of detection (1)
- Lymnaea stagnalis (1)
- MALDI-TOF MS (1)
- MC-TIMS (1)
- MST (1)
- Machine learning (1)
- Magnesium (1)
- Magnesium isotope ratios (1)
- Mass cytometry (1)
- Massenspektrometrie (1)
- Material sciences (1)
- Matrix-assisted laser desorption ionization–mass spectrometry imaging (MALDI-MSI) (1)
- Measuremment uncertainty (1)
- Medicinal application (1)
- Mercury speciation (1)
- Mesoporous materials (1)
- Metal nanoclusters (1)
- Metal toxicity (1)
- Metal uptake (1)
- Metalloprotein (1)
- Method (1)
- Methylmercury (1)
- Metrology in Chemistry (1)
- Micro-sublimation (1)
- Microdroplet generator (1)
- Microplastic-induced effects (1)
- Microplatic (1)
- Mixture toxicity (1)
- Mobile phase (1)
- Mole (1)
- Molecular imaging (1)
- Multi-collector inductively coupled plasma-mass spectrometry (ICP-MS) (1)
- Multielementanalytik (1)
- Multielementanalytik in kurzen transienten Signalen (1)
- Multimodal (1)
- Multimodale Analytik (1)
- Multiple sclerosis (1)
- Multiple-injection sample-standard bracketing (1)
- Nano-carrier (1)
- Nanocluster (1)
- Nanoparticle characterization (1)
- Nanopartikel (1)
- Nickel chelate (1)
- Nitrogen microwave inductively coupled atmospheric pressure mass spectrometry (1)
- Non-metal analysis (1)
- Non-target (1)
- OBOC library (1)
- Oberflächengewässer (1)
- Oberflächenwasser (1)
- On-chip screening (1)
- On-line CE/MC-ICP-MS (1)
- One-bead-one-compound library (1)
- Ore provenance (1)
- Oxygen evolution reaction (1)
- Oxygen isotope ratios (1)
- Pb isotopes (1)
- Peptide aptamers (1)
- Peptides and Proteins (1)
- Per- and polyfluorinated alkly substances (PFASs) (1)
- Per- and polyfluoroalkyl substances (PFAS) (1)
- Photocatalysis (1)
- Plant tissue (1)
- Polarised light microscopy (1)
- Polishing (1)
- Pollutant (1)
- Pollution (1)
- Polyethylenimine (1)
- Polymer membrane (1)
- Pore fluids (1)
- Portland cement (1)
- Portland clinker (1)
- Priam's treasure (1)
- Primary calibration solution (1)
- Primary difference measurement method (PDM) (1)
- Primary transfer standards (PTSs) (1)
- Programmed cell death (1)
- Protein imaging (1)
- Provenance (1)
- Provenancing (1)
- Prozessanalytik (1)
- Prozessindustrie (1)
- Pt-based drugs (1)
- PtNP (1)
- Purity assessment (1)
- Quality assurance (1)
- Quantitative protein analysis (1)
- Radiogenic isotopes (1)
- Raman microspectroscopy (1)
- Raman spectroscopy (1)
- Recombinant protein (1)
- Reference (1)
- Reference Materials (1)
- Reference measurements (1)
- Remediation (1)
- Revision of the SI (1)
- River water (1)
- River water sulfate (1)
- SC-ICP-MS (1)
- SERS (1)
- SI-traceability (1)
- SPR (1)
- Sample-sample bracketing (1)
- Sapphire (1)
- Scale anchor (1)
- Scale conversion (1)
- Schwebstoffe (1)
- Seawater (1)
- Sediment (1)
- Selenium (1)
- Sensor (1)
- Serum (1)
- Sewage sludge (1)
- Silbernanopartikel (1)
- Silica diagenesis (1)
- Silicon (1)
- Silicon isotopes (1)
- Single Cell (1)
- Single cell analysis (1)
- Single cell-ICP-MS (1)
- Single cell-ICP-ToF-MS (1)
- Single-cell analysis (1)
- Soil (1)
- Soil available boron (1)
- Soils (1)
- Solid phase extraction (SPE) (1)
- Spark plasma sintering (1)
- Special issue (1)
- Special issue, young analytical scientists (1)
- Speciation analysis (1)
- Species-unspecific on-line isotope dilution (1)
- Spectrometer (1)
- Speroid (1)
- Spheroid (1)
- Sputtering (1)
- Sr and Nd isotope analysis (1)
- Sr isotope analysis (1)
- Stability (1)
- Stable isotopes (1)
- Standard atomic weight (1)
- Standardization (1)
- Statistical analysis (1)
- Strontium isotope (1)
- Sulfur isotopes (1)
- Sulphur isotope (1)
- Sum parameter (1)
- Surface plasmon resonance (1)
- Surface water (1)
- Surface waters (1)
- Synthetic peptides (1)
- Tantalum oxyfluorides (1)
- Tau (1)
- Test strips (1)
- Tetramethylammonium hydroxide (1)
- Thin tissue sections (1)
- Tissue (1)
- Tissue soldering (1)
- Titanium hydride (1)
- Total element content (1)
- Total element determination (1)
- Toxic elements (1)
- Toxicity (1)
- Transferrin (1)
- Transient signal (1)
- Trojan silver artefacts (1)
- Two-phase system (1)
- Umwelt-Speziation (1)
- Validation (1)
- WWTP (1)
- XRCD method (1)
- Xerogel (1)
- Ytterbium (1)
- Zinc (1)
- Zirconium (1)
- bell pepper (1)
- boron (1)
- delta value (1)
- isotope fractionation (1)
- lank characterization (1)
- measurement uncertainty (1)
- metabolism (1)
- silicon (1)
- spICP-MS (1)
- species-specific isotope information (1)
- tandard addition (1)
- Ägyptisches Museum Berlin (1)
- β-lactam (1)
Organisationseinheit der BAM
- 1.1 Anorganische Spurenanalytik (126) (entfernen)
Paper des Monats
- ja (4)
Here, we describe an optimized fast and simple extraction method for the determination of per- and polyfluorinated alkyl substances (PFASs) in soils utilizing high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR–CS–GFMAS). To omit the bias of the solid phase extraction (SPE) step commonly used during the analysis of extractable organically bound fluorine (EOF) we optimized a fast and simple SPE-free extraction method. The developed extraction method consists of a liquid-solid extraction using acidified methanol without any additional SPE. Four extraction steps were representative to determine a high proportion of the EOF (>80% of eight extractions). Comparison of the optimized method with and without an additional SPE clean-up step revealed a drastic underestimation of EOF concentrations using SPE. Differences of up to 94% were observed which were not explainable by coextracted inorganic fluoride. Therefore, not only a more accurate but also a more economic as well as ecologic method (bypassing of unnecessary SPE) was developed. The procedural limit of quantification (LOQ) of the developed method was 10.30 μg/kg which was sufficient for quantifying EOF concentrations in all tested samples. For future PFAS monitoring and potential regulative decisions the herein presented optimized extraction method can offer a valuable contribution.
A general method to carry out the fluorination of metal oxides with poly(tetrafluoroethylene) (PTFE, Teflon) waste by spark plasma sintering (SPS) on a minute scale with Teflon is reported. The potential of this new approach is highlighted by the following results. i) The tantalum oxyfluorides Ta3O7F and TaO2F are obtained from plastic scrap without using toxic or caustic chemicals for fluorination. ii) Short reaction times (minutes rather than days) reduce the process time the energy costs by almost three orders of magnitude. iii) The oxyfluorides Ta3O7F and TaO2F are produced in gram amounts of nanoparticles. Their synthesis can be upscaled to the kg range with industrial sintering equipment. iv) SPS processing changes the catalytic properties: while conventionally prepared Ta3O7F and TaO2F show little catalytic activity, SPS-prepared Ta3O7F and TaO2F exhibit high activity for photocatalytic oxygen evolution, reaching photoconversion efficiencies up to 24.7% and applied bias to photoconversion values of 0.86%. This study shows that the materials properties are dictated by the processing which poses new challenges to understand and predict the underlying factors.
The presence of microplastic (MP) particles in aquatic environments raised concern About possible enrichment of organic and inorganic pollutants due to their specific surface and chemical properties. In particular the role of metals within this context is still poorly understood. Therefore, the aim of this work was to develop a fully validated acid digestion protocol for metal analysis in different polymers, which is a prerequisite to study such interactions.
The proposed digestion protocol was validated using six different certified reference materials in the microplastic size range consisting of polyethylene, polypropylene, acrylonitrile butadiene styrene and polyvinyl chloride. As ICP-MS/MS enabled time-efficient, sensitive and robust analysis of 56 metals in one measurement, the method was suitable to provide mass fractions for a multitude of other elements beside the certified ones (As, Cd, Cr, Hg, Pb, Sb, Sn and Zn). Three different microwaves, different acid mixtures as well as different temperatures in combination with different hold times were tested for optimization purposes.
With the exception of Cr in acrylonitrile butadiene styrene, recovery rates obtained using the optimized protocol for all six certified reference materials fell within a range from 95.9% ± 2.7% to 112% ± 7%. Subsequent optimization further enhanced both precision and recoveries ranging from 103% ± 5% to 107 ± 4% (U; k = 2 (n = 3)) for all certified metals (incl. Cr) in acrylonitrile butadiene styrene. The results clearly show the analytical challenges that come along with metal analysis in chemically resistant plastics. Addressing specific analysis Tools for different sorption scenarios and processes as well as the underlying kinetics was beyond this study’s scope. However, the future application of the two recommended thoroughly validated total acid digestion protocols as a first step in the direction of harmonization of metal analysis in/on MP will enhance the significance and comparability of the generated data. It will contribute to a better understanding of the role of MP as vector for trace metals in the environment.
Polyethylene (PE) frits were used to quantify sulphur in copper and its alloys by isotope dilution combined with LA-ICP-MS as an alternative approach to conventional sample preparation: the copper samples were spiked, the spiked samples were dissolved, the resulting solutions were absorbed in the PE frits and finally the PE frits were analysed by LA-ICP-MS. A prerequisite for such a support material is a low sulphur blank and thus PE was selected for this purpose. The absorption efficiency of the PE frits was studied for varying sulphur amounts ranging from 2 mg S to 80 mg S showing that more than 99.5% of the loaded sulphur was absorbed by the frit. The so prepared PE frits were measured by LA-ICP-MS and yielded a good linearity (R2 ¼ 0.999) for the sulphur ion intensities corresponding to sulphur amounts up to 40 mg S; the associated sensitivity is approximately 3.4 x 10⁴ cps μg⁻¹ for ³²S. For the validation of the developed procedure the reference materials BAM-M376a, BAM-228 and BAM-227 were applied such that 2 μg S, 5 μg S and 11 μg S were absorbed in the PE frits, respectively. These samples were pre-quantified for the adsorbed sulphur amount by external calibration LA-ICP-MS yielding sulphur amounts of 0.9 μg, 5.1 μg and 8.5 μg (quantified for ³²S only), respectively. Relative Standard deviations of the isotope ratios were below 5% in average (n ¼ 3 lines) in all cases (except for the pure spike solution). These samples were then analysed by LA-ICP-IDMS and the measurement results were validated by comparing them with the results obtained by conventional ICP-IDMS. The obtained relative expanded measurement uncertainties ranged between 10% and 26%. Pearson's coefficient was used to express the correlation between both techniques; the obtained value was 0.999 demonstrating a strong correlation. Contrary to most published LA-ICP-IDMS procedures, the developed procedure enables SI-traceability for the measurement results. The metrological traceability to the SI for the sulphur mass fractions in copper was established by an unbroken chain of comparisons, each accompanied by an uncertainty budget. Thus, the measurement results are considered reliable, acceptable and comparable within the stated measurement uncertainty. The metrological traceability chain from the kg down to mass fraction in the samples obtained by LA-ICP-IDMS is presented as well.
Boron (B) is an essential micronutrient for plant growth. Lack of valid methods for pretreatment and measurement of δ11B in plant restrict applications of it in the biosphere. Dry ashing, one step cation exchange and micro-sublimation were combined to separate and purify boron (B) in plant tissues. The low procedure blank, high B recovery and the accurate δ11B values of the plant reference materials demonstrate that this method is suitable and valid for B pretreatment and δ11B measurement in plant samples by MC-ICP-MS. Based on this method, the δ11B in different plants (Brassica napus, Chenopodium album L, moss, lichen, and Nostoc commune) was analyzed. For Brassica napus, δ11B increased gradually from root to leaf, and then decreased to rapeseed. For the same parts, the δ11B increased from the lower parts to the higher parts. This variation may be due to the B(OH)3 transporter of NIP6;1 and the incorporation of B into the cell. The reason for lower δ11B values in shell and rapeseed compared to those in leaves presumably is to the preferred Transport of borate in the phloem. The largest δ11B fractionation between leaf and root in Brassica napus and Chenopodium album L was +24.2‰ and +26.6‰, respectively. The large variation and fractionation of δ11B within plants indicates that δ11B is a good tracer to study the B translocation mechanisms and metabolism within plants. The δ11B in Nostoc commune, lichen, and moss showed variations of -4.1‰ to +21.5‰, −9.4‰ to +7.3‰, and −18.3‰ to +11. 9‰, respectively. In the same site, δ11B in different plants ranked Nostoc commune>moss>lichen and δ11B in mosses growing in different environment ranked soil>tree>rock. Rain and soil available B are the main B sources for these plants. The δ11B in Nostoc commune, lichen, and moss may be a useful tracer to study the atmospheric B input. In the future, plants culture experiments under certain environments and studies from molecular level are necessary to decipher the variation of δ11B and fractionation mechanisms within plants.
ADAMTS4-specific MR-probe to assess aortic aneurysms in vivo using synthetic peptide libraries
(2022)
The incidence of abdominal aortic aneurysms (AAAs) has substantially increased during the last 20 years and their rupture remains the third most common cause of sudden death in the cardiovascular field after myocardial infarction and stroke. The only established clinical parameter to assess AAAs is based on the aneurysm size. Novel biomarkers are needed to improve the assessment of the risk of rupture. ADAMTS4 (A Disintegrin And Metalloproteinase with ThromboSpondin motifs 4) is a strongly upregulated proteoglycan cleaving enzyme in the unstable course of AAAs. In the screening of a one-bead-one-compound library against ADAMTS4, a low-molecular-weight cyclic peptide is discovered with favorable properties for in vivo molecular magnetic resonance imaging applications. After identification and characterization, it’s potential is evaluated in an AAA mouse model. The ADAMTS4-specific probe enables the in vivo imaging-based prediction of aneurysm expansion and rupture.
A systematic series of industrial-relevant polystyrene-based anion exchange resins that are functionalized with hydro- or fluorocarbon chains are compared regarding their adsorption behavior toward perfluorocarboxylic acids (PFCA) in respect to their charge, chain length, and type of chain. The results clearly show the dominance of electrostatic interactions in the adsorption process as uncharged adsorber materials showed no adsorption at all. In contrast, the charged adsorber materials showed in general a PFCA removal of 80% to 30% over the experiment depending on effluent fraction.
Unexpectedly, for perfluorobutanoic acid (PFBA) the highest removal rate is found with consistently >90%. Despite observing significant benefits in the adsorption of PFCA for fluoroalkylated adsorbers in comparison to their non-fluorinated counterparts, this effect of fluoroalkylation is comparatively small and can not be clearly attributed to fluorophilic interactions between the fluoroalkyl chains. These findings help clarifying that the introduction of fluorocarbon moieties in adsorber materials is not necessary in order to remove fluorocarbon molecules from the environment.
Laser tissue soldering (LTS) based on indocyanine green (ICG)-mediated heat- denaturation of proteins might be a promising alternative technique for micro-suturing, but up to now the Problem of too weak shear strength of the solder welds in comparison to sutures is not solved. Earlier reports gave promising results showing that solder supported by carrier materials can enhance the cohesive strength of the liquid solder. In these studies, the solder was applied to the carriers by dip coating. Higher reliability of the connection between the solder and the carrier material is expected when the solder is bound covalently to the carrier material. In the present study a poly(ether imide) (PEI) membrane served as carrier material and ICG- supplemented albumin as solder substrate. The latter was covalently coupled to the carrier membrane under physiological conditions to prevent structural protein changes. As laser source a diode continuous-wave laser emitting at 808 nm with intensities between 250mW and 1500mW was utilized. The Albumin functionalized carrier membrane was placed onto the tunica media of explanted pig thoracic aortae forming an overlapping area of approximately 0.5×0.5 cm2. All tests were performed in a dry state to prevent laser light absorption by water. Infrared spectroscopy, spectro-photometrical determination of the secondary and Primary amine groups after acid orange II staining, contact angle measurements, and atomic force microscopy proved the successful functionalization of the PEI membrane with albumin. A laser power of 450mW LTS could generate a membrane-blood vessel connection which was characterized by a shear strength of 0.08±0.002MPa, corresponding to 15% of the tensile strength of the native blood vessel. Theoretically, an overlapping zone of 4.1mmaround the entire circumference of the blood vessel could have provided shear strength of the PEI membrane-blood vessel compound identical to the tensile strength of the native blood vessel. These in-vitro results confirmed the beneficial effects of solder reinforcement by carrier membranes, and suggest LTS with covalently bound solders on PEI substrates for further studies in animal models.
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been revealed as a convenient technique for trace elemental imaging in tissue sections, providing elemental 2D distribution at a quantitative level. For quantification purposes, in the last years several approaches have been proposed in the literature such as the use of CRMs or matrix matched standards. The use of Isotope Dilution (ID) for quantification by LA-ICP-MS has been also described, being mainly useful for bulk analysis but not feasible for spatial measurements so far. In this work, a quantification method based on ID analysis was developed by printing isotope-enriched inks onto kidney slices from rats treated with antitumoral Pt-based drugs using a commercial ink-jet device, in order to perform an elemental quantification in different areas from bio-images. For the ID experiments ¹⁹⁴Pt enriched platinum was used. The methodology was validated by deposition of natural Pt standard droplets with a known amount of Pt onto the surface of a control tissue, where could be quantified even 50 pg of Pt, with recoveries higher than 90%. The amount of Pt present in the whole kidney slices was quantified for cisplatin, carboplatin and oxaliplatin-treated rats. The results obtained were in accordance with those previously reported. The amount of Pt distributed between the medullar and cortical areas was also quantified, observing different behavior for the three drugs.
Per- und polyfluorierte Alkylverbindungen (PFAS) sind eine Substanzklasse bestehend aus mehreren tausenden Einzelverbindungen. Unter PFAS zählen alle Verbindungen, die mindestens eine perfluorierte Methyl- (-CF3) oder Methylen-Gruppe (-CF2-) besitzen. Somit zählt auch ein großer Teil der fluorierten Medikamente, Pflanzenschutzmittel oder Biozide in die PFAS-Substanzklasse. Aufgrund der Persistenz, Bioakkumulation in Nahrungsketten, Toxizität und der ubiquitären Verbreitung von PFAS zählen sie zu den „emerging pollutants“. Die PFAS-Analytik ist wegen ihrer vielfältigen physikalisch-chemischen Eigenschaften und der sehr hohen Anzahl an PFAS eine große Herausforderung. Da es für viele Anwendungen noch ungewiss ist, welche PFAS verwendet werden, wie sie in die Umwelt gelangen und welche Transformations- bzw. Abbauprodukte entstehen, stoßen analytische Ansätze, die nur auf Einzelsubstanzen abzielen, hier an ihre Grenzen. PFAS-Summenparameter-Methoden, die darauf abzielen ein möglichst vollständiges Abbild der PFAS-Belastungssituation widerzuspiegeln, werden daher immer wichtiger.