{
  "abstract": "Stable isotope analysis of nitrogen (N) at natural abundance provides key insights into biochemical processes. However, position-specific isotope analysis (PSIA) of 15 N remains technically challenging due to the low sensitivity of conventional approaches. The approach we present here relies on resolving the 1 H– 15 N doublets embedded within dominant 1 H– 14 N triplets and quantifying them via spectral deconvolution under rigorously optimized quantitative NMR conditions. Using ammonium chloride as a model, we established the experimental and processing parameters required for precision (≤ 2‰) and trueness (< 3‰), validated against isotope ratio monitoring Mass Spectrometry (irm-MS). The method was successfully extended to structurally more complex compounds (aniline, indole, urea, and N-acetylated tryptophan methyl ester), achieving accurate position-specific δ 15 N determinations. Importantly, we demonstrate the feasibility of applying this strategy to a human urine sample, enabling direct δ 15 N measurement of endogenous urea in a complex biological matrix at natural abundance. This non-destructive method requires minimal sample amounts and offers a robust complement to irm-MS, expanding the analytical toolbox for nitrogen isotope research in environmental, biochemical, and biomedical contexts.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "name": "Maylis Couton"
    },
    {
      "name": "Margot Sanchez"
    },
    {
      "name": "Valérie Fargeas"
    },
    {
      "name": "Illa Tea"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/djggevb4rhmtx.bib",
  "cited_by": 0,
  "doi": "10.1016/j.aca.2026.346112",
  "fulltext_url": null,
  "id": "djggevb4rhmtx",
  "issns": [
    "0003-2670"
  ],
  "landing_url": "https://hal.science/hal-05796092v1",
  "language": "en",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "hal",
      "0.chim"
    ],
    [
      "openalex",
      "1607|Advanced NMR Techniques and Applications"
    ]
  ],
  "openalex": "W7134954327",
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-12",
  "publisher": "Elsevier Masson",
  "ris": "https://research.draconitic.com/paper/djggevb4rhmtx.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:17:55Z",
      "native_id": "hal-05796092",
      "source": "hal",
      "url": "https://hal.science/hal-05796092v1"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "openalex:1607|Advanced NMR Techniques and Applications",
      "subfield": "physical"
    }
  ],
  "title": "Position specific 15N isotope analysis at natural abundance by 1H NMR",
  "title_text": "Position specific 15N isotope analysis at natural abundance by 1H NMR",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:17:55Z",
  "url": "https://research.draconitic.com/paper/djggevb4rhmtx",
  "venue": "Analytica Chimica Acta",
  "versions": []
}