New Dimensions in Isotope Ratio Analysis: Site Specificity

This is the third in a series on Isotope analysis using Orbitrap technology.

Wouldn’t it be incredible if you could look at a complex molecule such as an amino acid and determine the isotopic composition of the single carbon atom in the carboxyl group? Well, now you can, with the Thermo Scientific Orbitrap Exploris Isotope Solutions.

How does site specificity work?

The Orbitrap Exploris Isotope Solutions contains an “Ion-Routing Multipole” that takes intact molecules and performs controlled fragmentation. These fragments can then be routed to the Orbitrap Mass Analyzer to determine the isotopic composition of those fragments, in essence, specific atoms from a larger, more complex molecule.

Why is site specificity useful?

Site-specific isotope information has the potential to reveal fascinating insights into the processes forming the molecule. Take the example of isotope labeling in metabolomics — not only can we see that our label appears in a specific metabolite, the Orbitrap Exploris Isotope Solutions allows us to determine the atomic position in the molecule of the label. This would provide insight into the metabolic pathways that lead to the creation of that specific metabolite, giving an understanding of how the body processes certain molecules/foodstuffs.

Site-specific isotope information is not limited to biomedical applications. It also can be used to trace the production processes for key food products, such as vanillin, aiding food authenticity efforts. Similarly, site-specific isotope information can be used in the field of anti-doping and drugs testing, or the development of new geological climate proxies. The possibilities are endless.

For more information, visit: thermofisher.com/orbitrap-for-isotopes.

Part 1: Boost Your Productivity with the Isotopic Analysis of Intact Molecules

Part 2: New Dimensions in Isotope Ratio Analysis: Multiply Substituted Isotopologues