Skip to main content

δ13C (delta-13 C) is a natural, stable isotope of carbon with a nucleus containing six protons and seven neutrons. δ13C isotopic analysis, also referred to as an isotopic signature, is used for source attribution of carbon-based molecules. For example, stable carbon isotopes in carbon dioxide (CO2) are utilized differentially by photosynthesis. Therefore, δ13C isotopic signatures can be used directly as a source attribution for plants—such as place of origin and authenticity of plant-derived foods and beverages. It can also be used indirectly for analysis of the diets of plant-eating animals. This enables an understanding of animal eating patterns as well as the authenticity of food of animal origin.

δ13C isotopic analysis can also be used for source attribution of methane (CH4). Determining whether methane is biogenic or anthropogenic is essential to identifying its origin in groundwater near a hydraulic fracturing well, monitoring fugitive methane emissions from a landfill, or analyzing the biochemical pathways that produce and consume methane in wetlands.

Picarro has designed and produced several isotope analyzers that precisely measure δ13C in carbon dioxide and methane for laboratory and field studies.


Product Sort descending Measurements Applications

G2131-i Isotope and Gas Concentration Analyzer

The Picarro G2131-i isotope and gas concentration analyer precisely, simultaneously, and continuously measures δ13C in carbon dioxide (CO2) and CO2 and CH4 gas concentration for a range of applications from atmospheric and ocean science research to food and beverage origin and authenticity.

G2201-i Isotopic Analyzer

The Picarro G2201-i isotope analyzer precisely and continuously measures δ13C in carbon dioxide (CO2) and in methane (CH4) to help understand the biological and geological mechanisms that produce and consume CO2.