The origin and process tracing for molecules of biogeochemical interests throughisotopologue analysis featuring position specific isotope abundance of bioelements
Naohiro Yoshida1,2
1
Department of Chemical Science and Engineering, School of Materials and Chemical
Technology, Tokyo Institute of Technology
2
Earth-Life Science Institute, Tokyo Institute of Technology
Since the 1950’s, the stable isotope compositions of naturally occurring molecules havebeen proved to be a strong tool for the study of geological, biological, and anthropogenic
processes, and their evolution and effect on biogeochemical cycles of environmental
molecules. However, due to technical and conceptual limitations, the complete set of
information potentially contained in molecules remains largely unexplored especially in thedifferent modes of isotopic substitution as 1) to 3) stated below. We have developed series of
new methodologies that allow analysis of isotopically substituted molecules, through eachmode. We are also integrating those in the study of geological, biological and anthropogenic
processes which affect the Earth’s environment.
1) Position specific isotope abundance analysis (PSIA): We have pioneered PSIA ofnitrogen in N2O1,2) and of carbon and hydrogen in organic molecules using classic isotope massspectrometry3) and nuclear magnetic resonance4,5). We have shown that PSIA of hydrocarbons
and organic acids allows us to differentiate processes as distinguishing between biological andnon-biological processes4,6). 2) Mass-independent fractionation (MIF): The discovery of MIF of
sulfur and oxygen in terrestrial molecules has revolutionized environmental geochemistry andour understanding of the evolutionary history of the Earth's environment and life7-9). 3)
Clumped isotopes (i.e. isotopologues with 2 or more minor isotopes) provide uniqueinformation about the temperature history of molecules such as carbonates 10) or organic
compounds11-13).
We are currently developing new and improved tracers of environmental andbiogeochemical processes and apply them to the environmental diagnosis. We haveestablished and standardized new methods for the analyses of above 3 higher dimensionalmodes of isotopic substitution, and unifying them to develop ultimate environmental
diagnosis. The development and application of these new isotopic tools to the environment
evolution on the Earth, in modern and ancient eras, represents an important conceptualadvance in Earth and life sciences. This will open new areas of research about, for example,
the geological production of some atmospheric gases, metabolic processes and the biologicalfixation of atmospheric greenhouse gases, the production and cycling of pollutant gas byindustrial processes. As a whole, these new tracers will be integrated together for diagnosisof the Earth’s environment.
The research achievements so far obtained will be reviewed and a perspective will be
stated in this talk as I am currently leading a research project “Environmental diagnosis with

isotopologue tracers”, a Kiban-S grant-in-aid for 5 yrs until 2022, and co-editing “Handbook ofIsotopologue Biogeochemistry” 14).
References; 1)Yoshida & Toyoda, 2000 Nature; 2)Yamazaki, Toyoda, Yoshida, et al., 2014
Biogeosciences; 3)Yamada, Yoshida, et al., 2002 RCM; 4)Gilbert, Yamada, Yoshida, 2013 Anal.
Chem., and 5) Gilbert, Yamada, Yoshida, 2014 Anal. Chim. Acta; 6)Gilbert, Yamada, Ueno,
Yoshida 2016 Geochim. Cosmochim. Acta; 7)Danielache, Ueno, Yoshida et al., 2008 J. Geophys.
Res.; 8)Hattori, Danielache, Ueno, Yoshida et al., 2013 PNAS, 9)Ueno, 2015 Science; 10)
Yoshida, Abe, Yamada et al., RCM, 2013; 11)Tsuji, Yamada, Yoshida et al., 2012 Sensor;: 12)Onoet al., 2014 Anal. Chem.; 13)Stolper et al., 2014 Science; 14)Yoshida, Gilbert, Foriel eds,
Handbook of Isotopologue Biogeochemistry, 2019 to be published by Springer-Nature.