Articles | Volume 19, issue 6
https://doi.org/10.5194/amt-19-2265-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-19-2265-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
01 Apr 2026
Research article |
| 01 Apr 2026
| 01 Apr 2026
Fast and reproducible δ13C-CO2 analysis from 1 mL of ambient atmospheric air using continuous-flow IRMS: from sampling to storage to analysis
Ecotron Européen de Montpellier (UAR 3248), Univ Montpellier, CNRS, Montferrier-sur-Lez, France
Marie-Laure Tiouchichine
Ecotron Européen de Montpellier (UAR 3248), Univ Montpellier, CNRS, Montferrier-sur-Lez, France
Alexandru Milcu
Ecotron Européen de Montpellier (UAR 3248), Univ Montpellier, CNRS, Montferrier-sur-Lez, France
CEFE, Univ Montpellier, CNRS, EPHE, IRD, 34293, Montpellier, France
Clément Piel
Ecotron Européen de Montpellier (UAR 3248), Univ Montpellier, CNRS, Montferrier-sur-Lez, France
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Short summary
We present a simple workflow for high-precision δ¹³C-CO₂ analysis from 1 mL air samples using cryogenic pre-concentration and continuous-flow isotope-ratio mass spectrometry (IRMS). The method combines vial conditioning, dual sealing, and −80 °C storage to minimise gas loss. It achieves ±0.1 ‰ precision and stable isotopic values for up to one week of storage. This low-cost approach enables high-frequency δ¹³C-CO₂ measurements in volume-limited systems such as microcosm or chamber experiments.
We present a simple workflow for high-precision δ¹³C-CO₂ analysis from 1 mL air samples using...
