Page 196 - Pharmaceutics IV (02-06-01305)

Temperature &pressure are not included in the list of radiation safer
consideration.Handling a radioactive compound under refrigerated

conditions does not provide any lower exposure to radiation than
handling the same compound at room temperature. The decay rate
of radionuclides is insensitive to temperature& pressure under
normal usual laboratory operating conditions.

Biomedical Applications of Radiopharmaceuticals:

About 200 radioisotopes are in current medical use . It can be
employed as radiation sources, for radiotherapy application ,or as
radioactive tracers, which are commonly used as diagnostic agents.
They are also used to determine the biodistribution of particular
Compounds (in which those radioisotopes are incorporated.

1-Radioactive tracers &diagnosis

Use of radioisotopes as tracers & diagnostic agents depends on:

a- The ease of detection of radiation emitted by the isotope
b- B-The ability of the isotopic element to be incorporated into the

molecule that is being traced (such as during the biodistribution
studies of new drug candidates ).

1-As Diagnostic agents

Radioactive elements are typically adsorbed or incorporated on a
carries. e.g. use of radioisotopes for diagnosis of thyroid function
studies using low dose 131 I, erythrocyte studies using 14C, the 14C

Radioisotope detection in breath can be used to detect the presence

Of ulcer -causing bacteria Helicobacter pylori. Application in
cardiology ( e.g. myocardial perfusion) ,oncology ( e.g.

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