What is the process of isotopic labelling in chemistry?

Isotopic labelling is a technique used in chemistry to track the passage of an isotope through a reaction, metabolic pathway, or cell.

In more detail, isotopic labelling involves substituting one or more atoms in a molecule with an isotope. This isotope is usually a stable or radioactive variant of the same element, which allows scientists to track its movement and behaviour. The labelled atom can be detected due to its unique properties, such as its different mass or radioactive decay. This technique is particularly useful in studying chemical reactions and biological processes, as it provides a clear and precise way to observe how molecules interact and transform.

For example, in a chemical reaction, a scientist might replace one of the hydrogen atoms in a molecule with deuterium, a stable isotope of hydrogen. By observing how the deuterium behaves in the reaction, the scientist can gain insights into the reaction mechanism. Similarly, in biological research, isotopic labelling can be used to study metabolic pathways. A molecule containing a radioactive isotope can be introduced into an organism, and its progress through various metabolic processes can be tracked by monitoring the radiation.

Isotopic labelling is a powerful tool in chemistry and related fields. It allows for precise, detailed studies of complex processes, and can provide valuable insights into the fundamental mechanisms of chemistry and biology. However, it's important to handle isotopes with care, especially radioactive ones, due to their potential health risks.