A persulfate oxidation method for stable isotope analysis of dissolved organic carbon and the influence of inorganic ions on the results

- A persulfate oxidation method for measuring δ13C of DOC is developed.
- Samples are analyzed by gas chromatography-isotope ratio mass spectrometry.
- The precision is <0.5‰ for samples containing 6.3 μg or more of carbon.
- The reproducibility of multiple preparations is ±0.50‰.
- Inorganic ions in fresh water do not influence measurement accuracy.