Journal: Analytical Chemistry

Abbreviation

Anal. Chem.

Publisher

American Chemical Society

Journal Volumes

ISSN

1520-6882
0003-2700

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Publications 1 - 10 of 316
  • Metal Probe Microextraction Coupled to Dielectric Barrier Discharge Ionization–Mass Spectrometry for Detecting Drug Residues in Organisms
    Item type: Journal Article
    Lu, Qiao; Lin, Rongkun; Du, Chao; et al. (2020)
    Analytical Chemistry
  • Enantiomer-Specific Stable Carbon and Nitrogen Isotopic Analysesof Underivatized Individual L- and D‑Amino Acids by HPLC + HPLCSeparation and Nano-EA/IRMS
    Item type: Journal Article
    Sun, Yuchen; Blattmann, Thomas M.; Takano, Yoshinori; et al. (2024)
    Analytical Chemistry
    We developed a new method for stable carbon and nitrogen isotopic (δ13C and δ15N) analysis of underivatized amino acid (AA) enantiomers simultaneously, based on high-performance liquid chromatography (HPLC) separation and off-line isotopic measurement. l- and d-Enantiomers of each AA were isolated using a ReproSil Chiral-AA column, purified by wet chemical procedure, and analyzed for δ13C and δ15N values with a nanomol-scale elemental analyzer/isotope-ratio mass spectrometry (nano-EA/IRMS) system. We successfully achieved the separation of l- and d-enantiomers of 15 proteinogenous AAs, with all l-enantiomers eluting before respective d-enantiomers. The δ13C and δ15N values of AA enantiomers were consistent before and after HPLC separation, demonstrating that this analytical method conserves isotopic information. By coupling this column with a multidimensional HPLC system for isolating individual AAs, we analyzed l- and d-AAs in a natural sample, peptidoglycan isolated from Gram-positive bacterium Bacillus subtilis. Results show a surprisingly large 15N-depletion, up to 20‰, in d-glutamic acid relative to its l-counterpart. The first example, to our knowledge, of δ13C and δ15N analyses of underivatized AA enantiomers is expected to contribute to various research areas in the future.
  • Analysis of megadalton ions using cryodetection MALDI time-of-flight mass spectrometry
    Item type: Journal Article
    Wenzel, Ryan J.; Matter, Urs; Schultheis, Lothar; et al. (2005)
    Analytical Chemistry
  • High-Throughput, Quantitative Enzyme Kinetic Analysis in Microdroplets Using Stroboscopic Epifluorescence Imaging
    Item type: Journal Article
    Hess, David; Rane, Anandkumar; deMello, Andrew J.; et al. (2015)
    Analytical Chemistry
  • A Modified Traveling Wave Ion Mobility Mass Spectrometer as a Versatile Platform for Gas-Phase Ion–Molecule Reactions
    Item type: Journal Article
    Czar, Martin F.; Marchand, Adrien Henri; Zenobi, Renato (2019)
    Analytical Chemistry
  • Synchrotron Radiation/Fourier Transform-Infrared Microspectroscopy Study of Undesirable Water Inclusions in Solid-Contact Polymeric Ion-Selective Electrodes
    Item type: Journal Article
    Veder, Jean-Pierre; Patel, Kunal; Clarke, Graeme; et al. (2010)
    Analytical Chemistry
  • High-Mass Matrix-Assisted Laser Desorption Ionization-Mass Spectrometry of Integral Membrane Proteins and Their Complexes
    Item type: Journal Article
    Chen, Fan; Gerber, Sabina; Heuser, Katrin; et al. (2013)
    Analytical Chemistry
  • Vapor-Phase Infrared Laser Spectroscopy
    Item type: Journal Article
    Bartlome, Richard; Rey, Julien M.; Sigrist, Markus W. (2008)
    Analytical Chemistry
  • In Vitro Fossilization for High Spatial Resolution Quantification of Elements in Plant-Tissue Using LA-ICP-TOFMS
    Item type: Journal Article
    Becker, Pascal; Nauser, Thomas; Wiggenhauser, Matthias; et al. (2024)
    Analytical Chemistry
    Laser ablation in combination with an inductively coupled plasma time-of-flight mass spectrometer (LA-ICP-TOFMS) is an upcoming method for rapid quantitative element mapping of various samples. While widespread in geological applications, quantification of elements in biotissues remains challenging. In this study, a proof-of-concept sample preparation method is presented in which plant-tissues are fossilized in order to solidify the complex biotissue matrix into a mineral-like matrix. This process enables quantification of elements by using silicone as an internal standard for normalization while also providing consistent ablation processes similar to minerals to reduce image blurring. Furthermore, it allows us to generate a quantitative image of the element composition at high spatial resolution. The feasibility of the approach is demonstrated on leaves of sunflowers (Helianthus annuus), soy beans (Glycine max), and corn (Zea mays) as representatives for common crops, which were grown on both nonspiked and cadmium-spiked agricultural soil. The quantitative results achieved during imaging were validated with digestion of whole leaves followed by ICP-OES analysis. LA-ICP-TOFMS element mapping of conventionally dried samples can provide misleading trends due to the irregular ablation behavior of biotissue because high signals caused by high ablation rates are falsely interpreted as enrichment of elements. Fossilization provides the opportunity to correct such phenomena by standardization with Si as an internal standard. The method demonstrated here allows for quantitative image acquisition without time-consuming sample preparation steps by using comparatively safe chemicals. The diversity of tested samples suggests that this sample preparation method is well-suited to achieve reproducible and quantitative element maps of various plant samples.
  • Mineral Phase-Resolved Quantification in LA-ICP-MS Imaging
    Item type: Journal Article
    Umfahrer, Barbara; Buday, Jakub; Pořízka, Pavel; et al. (2025)
    Analytical Chemistry
    Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS), particularly in its time-of-flight (TOF) configuration, enables rapid, high-resolution elemental imaging across complex geological materials, offering spatial and chemical insights at the micrometer scale. However, quantitative accuracy is often limited in fine-grained or mineralogically heterogeneous matrices due to the failure of global normalization strategies, such as 100 wt % oxide assumptions, to account for mixed-phase compositions. Here, we present a workflow that leverages Uniform Manifold Approximation and Projection (UMAP) for unsupervised dimensionality reduction and k-means clustering to segment mineralogical phases directly from per-pixel elemental concentration maps. Cluster compositions are matched to known minerals based on stoichiometric similarity, enabling pixel-wise, phase-specific normalization (e.g., oxides vs carbonates). Validated with dawsonite-bearing sandstones from Mt. Amiata, Italy, this approach significantly reduces quantification errors, correcting systematic over- or underestimations of up to 60%. The method also enables a consistent, phase-resolved geochemical comparison across depth profiles. This study establishes UMAP not only as an exploratory tool but also as a practical guideline for accurate and interpretable quantification in multielemental imaging.
Publications 1 - 10 of 316