The use of isotopes in medicine - Essay Example

This physical difference explains why a process like fractional distillation can be used to separate isotopes. According to Van der Merwe (2002), due to the difference, a single element has the capability of existing in many forms for instance oxygen can exist as oxygen- 15, oxygen- 16 or oxygen- 17. This paper aims having a comprehensive discussion of isotopes, outlying their uses in archeology as well as looking at the future of isotopes in this area of interest. Isotopes are categorized into two main groups; stable and unstable.

White (1998) asserts that stable isotopes are those that do not decay over time, while the unstable ones undergo through an ionizing radiation referred to as radioactivity. Isotopes that give off this ionizing radiation are called radioisotopes, for example, carbon- 14 is a carbon radioisotope. In fact, the radioactive process differs from one isotope to the other hence some isotopes have a higher radioactive rate than others. The difference in the radioactivity rate depends on the ratio between neutrons number and proton number.

The higher the ratio the faster the rate and vise versa. Ambrose (2003) explains that the decay rate of isotopes can easily be predicted and determined, thus has widely been used in determining age mostly in archeology. Uses in Archeology Carbon Dating Carbon dating is the most common use of isotopes in archeology where age of organisms is determined in the process (McKinney, et al, 1995). The isotope used in this case is carbon- 14. Normally carbon exists in the C- 12 form, but in few occasions it also exists as C- 14.

C- 14 are radioisotopes hence can undergo a radioactive process at a specified rate of the half-life. According to the half-life rate, the proportion of decay is in such a way that the C- 14 to C-12 proportion is always constant. However, this is an unproven assumption that archeology attach to this theory of dating in order to assign ages to their discoveries (Van der Merwe, 2002). The theory is based on the changes that occur to a living organism when it dies and the process of decay starts.

According to the theory, during the living period of an organism, the carbon (C-12 and C-14) proportion in the organisms’ body and that in the environment is equal (White, 1998). This is so because the organism exists in an equilibrium environment as different metabolic processes take place within the organism, causing exchanges between the organism and its environment. In the process organisms are constantly replacing body molecules, a process that is faster in some tissues (skin), and slow in others (bone).

However, upon death, the unstable form of carbon (C- 14) will start decaying without being replaced from the environment through radioactivity. Consequently, if some parts of the organism such as bones are found by an archeologist, the ratio of C-12: C- 14 at the time can be used to ascertain when the organism died (Van der Merwe, 2002). An organism that died recently will have a lower ration than the one that died ages ago. Material Classification The isotopes used in this process are mainly those of oxygen through a closer analysis of the ratio of O- 18: O- 16.

Ambrose (2003) contends that archeologists use this method in the classification of the different types of glasses as well as in the analysis of mollusk shells as they try to determine their origins and sources. In