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Archaeological materials, such as bone, organic residues, hair, or sea shells, can serve as substrates for isotopic analysis. Carbon, nitrogen and zinc isotope ratios are used to investigate the diets of past people; these isotopic systems can be used with others, such as strontium or oxygen, to answer questions about population movements and cultural interactions, such as trade.
Oxygen isotope ratios are measured relative the standard, V-SMOW (Vienna Standard Mean Ocean Water). Isotope-ratio mass spectrometer used to measure stable isotope ratios, with gas bench in foreground. It is critical that the sample be processed before entering the mass spectrometer so that only a single chemical species enters at a given time.
Federal and state nuclear regulatory agencies keep records of the radionuclides used. [4] As of 2003 the isotopes Antimony-124, argon-41, cobalt-60, iodine-131, iridium-192, lanthanum-140, manganese-56, scandium-46, sodium-24, silver-110m, technetium-99m, and xenon-133 were most commonly used by the oil and gas industry because they are easily ...
Nitrogen-15, or 15 N, is often used in agricultural and medical research, for example in the Meselson–Stahl experiment to establish the nature of DNA replication. [12] An extension of this research resulted in development of DNA-based stable-isotope probing, which allows examination of links between metabolic function and taxonomic identity of microorganisms in the environment, without the ...
Many other isotopes have been used in specialized radiopharmacological studies. The most widely used is 67 Ga for gallium scans. 67 Ga is used because, like 99m Tc, it is a gamma-ray emitter and various ligands can be attached to the Ga 3+ ion, forming a coordination complex which may have selective affinity for particular sites in the human body.
Position-specific isotope analysis, also called site-specific isotope analysis, is a branch of isotope analysis aimed at determining the isotopic composition of a particular atom position in a molecule. Isotopes are elemental variants with different numbers of neutrons in their nuclei, thereby having different atomic masses. Isotopes are found ...
It is known and used for its ability to detect metals and several non-metals in liquid samples at very low concentrations. It can detect different isotopes of the same element, which makes it a versatile tool in isotopic labeling. Compared to atomic absorption spectroscopy, ICP-MS has greater speed, precision, and sensitivity.
The δ values and absolute isotope ratios of common reference materials are summarized in Table 1 and described in more detail below. Alternative values for the absolute isotopic ratios of reference materials, differing only modestly from those in Table 1, are presented in Table 2.5 of Sharp (2007) [1] (a text freely available online), as well as Table 1 of the 1993 IAEA report on isotopic ...