Stable isotope analysis

Stable isotope analysis (SIA) is the identification of isotopic signature, abundance of certain stable isotopes of chemical elements within organic and inorganic compounds. The isotopic composition of matter is controlled by different physical, chemical, and biological mechanisms. The different transformations of such matter can be followed through stable isotope analysis. So, the accurate stable isotope techniques have allowed the analysis of a wide variety of matrices and it has skyrocketed within different scientific fields such as geochemistry, archaeology, forensic science, biomedicine, environmental science, microbiology, soil science, and doping and fraud control, etc.

Alfa Chemistry has global experimental and analysis abilities based on our comprehensive technical platforms and professional R&D team. We can provide you with rigorous SIA to ensure reliable analysis results.

Principle of SIA

In nature, the stable isotope ratio (such as 13C/12C) of substance in different regions is different due to geological changes, climate changes, biological activities and metabolism and other factors of isotope fractionation. That is, the stable isotope ratio of the same substance in different regions is different. Similarly, for humans and animals, the stable isotope ratios of substances in the food they eat, the water they drink and the air they breathe are different in different regions and space-time. Through the metabolism of various organisms, the stable isotope ratios of elements in different body tissues are also different. Thus, the desired information can be inferred from stable isotope analysis of materials and tissues. There are many stable isotopes that are used, but the ones that are most widely analyzed are:

  • Hydrogen: D and 1H
  • Nitrogen: 15N (or N-15) and 14N (or N-14)
  • Carbon: 13C (or C-13) and 12C (or C-12)
  • Oxygen: 18O (or O-18) and 16O (or O-16)

The ratio between the two isotopes is normally referred to as δ, such as the ratio of 13C/12C is δ13C (pronounced: delta-13-C) values.

Alfa Chemistry's SIA Service Items

Service fieldsMain isotopes measuredService items
GeologyCarbon (δ13C), hydrogen (δD), oxygen (δ18O), sulfur (δ34S)1. Study on the sources and interactions of atmospheric, hydrosphere and lithosphere materials
2. Study on stable isotope thermometry
EcologyCarbon (δ13C), hydrogen (δD), nitrogen (δ15N)1. Studies on nutrient flow
2. Study on feeding habits, nutrient levels relationship and structure of food chain in animals
3. Study on the migratory habits of animals
4. Study on the relationship between animals and plants
5. Study on the vegetation water use and plant photosynthetic efficiency
6. Study on the climate change and regulation
HydrologyHydrogen (δD), oxygen (δ18O)1. Study on isotopic distribution of natural precipitation
2. Study on isotope variation during evaporation of water body
3. Determination of groundwater age and recharge source
4. Study on the mechanism of runoff generation in watershed
Food quality and safetyCarbon (δ13C), hydrogen (δD), nitrogen (δ15N), oxygen (δ18O), sulfur (δ34S)1. Study on animal products authenticity and traceability (such as meat, milk)
2. Study on plant products authenticity and traceability (such as cereal crops, wine, oil)
PaleobiologyCarbon (δ13C), hydrogen (δD), nitrogen (δ15N), oxygen (δ18O), sulfur (δ34S)1. Study on the biology of the extinct species
2. Study on the environmental conditions of mammals experienced
3. Study on the diet, habitat preferences, and physiology of mammals
OthersCarbon (δ13C), nitrogen (δ15N)1. Study on the sources of explosives, accelerants, drugs and etc.
2. Determination of doping and fraud control

The above items are only part of the test items in Alfa Chemistry. Please contact us for more service information.

Alfa Chemistry's SIA Instrument Platform

We have a wealth of instruments and equipments to meet the experimental and analytical needs, and some of them are as follows.

Ordering Process

Ordering Process

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  1. Wang J. and Yao H. Applications of DNA/RNA-stable isotope probing (SIP) in environmental microbiology[M]. Methods in Microbiology. Academic Press, 2021, 48: 227-267.
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