In Situ Carbon Stable isotope Analysis of Organic Carbon by Laser Ablation-Isotope Ratio Mass Spectrometry

An interface of laser ablation (LA) and stable isotope ratio mass spectrometry (IRMS) was developed to provide high spatial resolution organic carbon stable isotope analysis. Based on this, a LA-IRMS 13C/12C analytical method for organic carbon in standards and rice leaf was developed. The results showed that this system could carry out continuous on-line analysis of solid samples with high sensitivity, and the sampling amount was as low as tens of nanograms, which was 10000 times lower than that of traditional element analyzer (EA)-IRMS analysis. This method avoided many fractionation factors effectively in the process of sampling, transmission and ionization, and obtained repeatable and high-precision results. Combined with the advantages of laser ablation technique in situ sampling, the high-resolution carbon isotope distribution information of solid samples was obtained by using this method. This in-situ solid organic carbon isotope measurement technique was stable, reliable with high accuracy, and it would have a broad application prospect in the fields of environment, agriculture, forestry and ecology in the future. © 2020 Changchun Institute of Applied Chemistry, Chinese Academy of Sciences