Isotooppileimausten

Isotooppileimausten, or isotope labeling, is a technique used to track the path of specific atoms or molecules within a chemical or biological system. This is achieved by substituting one or more atoms in a molecule with an isotope of that element. Isotopes are atoms of the same element that have different numbers of neutrons, and therefore different atomic masses. Common isotopes used for labeling include stable isotopes like deuterium (heavy hydrogen), carbon-13, and nitrogen-15, as well as radioactive isotopes like tritium (radioactive hydrogen) and carbon-14.

The labeled molecules behave chemically and biologically in virtually the same way as their unlabeled counterparts, but their unique mass or radioactivity allows them to be distinguished from the natural abundance of the element. Detection of the labeled atoms is typically done using mass spectrometry for stable isotopes, or scintillation counting or autoradiography for radioactive isotopes.

Isotope labeling has a wide range of applications. In biology and medicine, it is used to study metabolic pathways, drug metabolism and distribution, protein synthesis, and the mechanisms of diseases. In chemistry, it helps in understanding reaction mechanisms, determining the origins of atoms in reaction products, and studying molecular diffusion. Environmental science also utilizes isotope labeling to trace pollutants, study nutrient cycles, and understand hydrological processes. The choice between stable and radioactive isotopes depends on the specific application, sensitivity requirements, and ethical or safety considerations. Stable isotopes are generally preferred when radioactivity is not necessary, due to their safety and the potential for long-term studies without radioactive decay concerns.