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Iodine-131 is used for thyroid, Iridium-192 for head There are three primary ways of creating
& breast, iodine-125 or palladium-103 for prostrate. Mo99
Localised targeting of tumours by this procedure
effectively destroys cancerous cells, and overall
radiation to the body is reduced. Targeted Alpha
Therapy (TAT) using bismuth-213 & lead-212 are newer Fission of uranium-235 (U-235) using HEU (Highly
treatments for leukaemia, cystic glioma, & melanoma Enriched Uranium) targets and newer method LEU
and treat pancreatic, ovarian, and melanoma cancers. (Low Enriched Uranium) targets

Boron-10 or gadolinium-157 are concentrated in Neutron capture of molybdenum-98 (Mo-98)
malignant brain tumours, and the patient is irradiated
with neutrons and protons. The Boron absorbs these N
particles and produces high energy alpha which kills
the cancerous cells. This experimental development
technique Neutron Capture Enhanced Particle Therapy
(NCEPT) requires the terminally ill patient to be
irradiated in a reactor facility.
235 U 98 Mo
Sterilisation

Co-60 source provides Gamma rays for cheap and
effective sterilisation of disposable syringes, surgical
instruments, surgical gloves, solutions, ointments,
powders and biological preparations for heart valves, 236 U 99 Mo
skin, tissue graft, bone, nerve. It is also used for
bandages, plastic and rubber sheets, cotton wool, and N 99 Mo
burn dressings. Blood for transfusions kits is sterilised
using Cs-137. Sterilisation provided by radiation has N
indefinite shelf life until it is exposed to air and can Other
perform on fully packed items. FPs 99 Mo

Production of Radioisotopes
Source: https://www.ncbi.nlm.nih.gov/books/NBK215146/

The Radioisotopes, as mentioned above, are all Using ACCELERATOR
produced in Nuclear Reactors or Cyclotrons/
Accelerators. The most in-demand Isotope is Mo99 from
which Tc99 is obtained. This is because as mentioned 1. Photo-fission reaction: 238U(γ,fission)99Mo
above used in over 85% of Nuclear procedures as
shown below 2. Photonuclear reaction: 100Mo(γ,n)99Mo

Brain Imaging Liver Imaging 3. Photo-neutrons generated from the e- beam for
99m Tc-ECD 99m Tc-Phytate
99m Tc-TRODAT 99m Tc-Sulphur fission LEU in solution
Colloid
99m Tc-Mebrofenin 4. D-T neutron generators to fission LEU in solution:
Cardiac Imaging
99m Tc-MIBI Sentinel Lymph 235U(n, fission)99Mo
99m Tc-Tetrofosmin Node Detection
Sn-Pyrophosphate 99m Tc-HSA 5. Spallation neutron source production (ADS):
Nanocolloid
235U(n,fission)99Mo
Tumor Imaging
Kidney Imaging
99m Tc-GHA 99m Tc(V)-DMSA 6. Direct Tc-99m production by cyclotron:
99m Tc(III)-DMSA 99m Tc-HYNICTOC
99m Tc-DTPA & Bone Imaging 100Mo(p,2n)99mTc
99m Tc-EC 99m Tc-MDP
The fission method is used in 95% and 98% of Mo-99
Source: https://www.britatom.gov.in/sites/default/files/ production currently.
Publications/RPH_exhibit.pdf

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