Radiopharmaceuticals are a group of drugs that are radioactive which have a diagnostic or therapeutic purpose. The radioactive atoms used in these drugs are produced in four different types of ways: nuclear fission, neutron activation, cyclotrons and generators. Nuclear fission is used to obtain the by-products (meaning the results of the decay) of the fission of U-235, which is a type of radioactive uranium that is found in nature. The fission of U-235 creates many more radioactive atoms, specifically two (Mo-103 and Sn-131) that are used in radiopharmaceuticals.
They emit gamma radiation which is most preferred in this drug. The second way we produce radioactive atoms is through neutron activation. This is where atoms are placed in a nuclear reactor, where they are bombarded with free neutrons. The atoms will capture the neutrons which increase the number of neutrons and mass in the nucleus. This excess energy is released as radiation. The third process that can be used is with cyclotrons.
Cyclotrons are machines where charged particles (loss or excess of electrons) are accelerated by an electromagnetic field (which contains magnetic and electric components which create a force on the particles) in a vacuum. The vacuum box is to ensure that no other matter is interfering with this process. The particles travel in a spiral motion and after they reach a high speed they are lead into a path.
They eventually crash into specific atoms which capture these particles to create a radioactive atom. So, magnetic and electric energy are converted into kinetic energy given to the particle, which is then captured by an atom. This creates an excess in mass, where this energy is released as radiation.
The last method involves using a radioisotope generator. A generator is used when we want to obtain a radioactive particle with a short half-life. Firstly, a radioisotope with a long half-life is obtained using one of the methods above. Then, this radioisotope is placed in the generator. It decays into a radioisotope with a short half-life.
The device can chemically separate it from the radioisotope with a longer half-life. The radioactive atoms produced by one of these four methods are then chemically attached to a drug, which depends on the specific use of the radiopharmaceutical. Radiopharmaceuticals are used for diagnostic or therapeutic purposes in hospitals. They can be used as therapeutic treatments by killing cancer cells by emitting strong radiation with high amounts of energy. The drug attached to the atom that emits radiation carries it to a specific part of the body that contains the cells that need to be killed. They can also be used for diagnostic purposes.
The drug will carry the radioactive atom to a part of the body. We can then use a camera which detects radiation (such as gamma) to show where this radiation is most concentrated. To diagnose a disease such as cancer, healthy tissues will metabolise (where the cell takes and handles) the radiopharmaceutical being given to it at a different extent than of organs/tissues with a disease or problem. Through the gamma radiation detection machine we can see where a tumor or infection is, for example.
The efficiency of radiopharmaceuticals depends on the half-life of the radioactive atoms and the type of radiation being emitted. A radioactive atom with a high radiation but short half-life is ideal for diagnostic purpose because the machine needs a certain amount of radiation to detect it, and if the radiation is too low the body will absorb it and it won’t end up outside of the body where the machine can see it. However, the atom should decay into a stable one fast (short half-life) so that the patient won’t get a lot of radiation, which is harmful. The radiation is only useful when the machine is trying to detect it.
In terms of therapeutic purposes, the radiation is usually high so that it can kill cells, but this means it could also kill healthy cells, which is not useful. This would lower the efficiency of the radiopharmaceutical.An environmental drawback of radiopharmaceuticals is that it can produce nuclear waste. However the process of making radiopharmaceuticals is completely environmentally friendly.In conclusion, radiopharmaceuticals are an environmentally friendly and somewhat efficient way to diagnose or essentially cure a disease, and can be produced easily through the process of nuclear reactions.