Vitamin B12, also known as cyanocobalamin, is a water-soluble vitamin that is part of the B vitamin family. B vitamins help support adrenal function, help calm and maintain a healthy nervous system, and are necessary for key metabolic processes.
For each of the 80 stable elements, the number of the stable isotopes is given. Only 90 isotopes are expected to be perfectly stable, and an additional 163 are energetically unstable, but have never been observed to decay. Thus, 253 isotopes (nuclides) are stable by definition (including tantalum-180m, for which no decay has yet been observed).
Isotopes utilized in nuclear medicine fall into two broad categories: Stable and Unstable. Stable isotopes do not undergo radioactive decay. WHAT IS A STABLE ISOTOPE? A stable isotope is any of two or more forms of an element whos nuclei contains the same number of protons and electrons, but a different number of neutrons. Stable isotopes remain unchanged indefinitely, but unstable (radioactive) isotopes undergo spontaneous disintegration.