3. INTRODUCTION
Radiopharmacetical :- These are the compound and
substance which emit radiation and which are used in
medicine are called Radiopharmacetical.
Radio isotopes, radioactive isotope , radio nucleus and
isotope are used generally for substance which emit
ionizing radiation.
3
4. All the substance made of atom.
Isotope :- the atom have the same number of
proton but different number of nutron.
4
-
++
-
-
+
-
-
-
-
6. S.No. Characteristic Alpha Beta Gamma
1 Nature It have 2 proton and 2
neutron
It is same like a
electron
It is an electromagnetic wave
2 Charge +2 -1 0
3 Mass Relatively Large Very small No Mass
4 Speed Slow Fast Speed of light
5 Ionizing Strong Weak Very weak
6 Most dengerous When source is inside the
body
When source is
Outside the body
When source is outside the
body
6
7. ALPHA PARTICLE
Alpha particle made up of 2 proton and 2 neutron.
We can write them because they are the same as a
helium nucleus.
When a nucleus emit an alpha particle its atomic number
decrease by 2 and its atomic mass decrease by 4.
Alpha particle are relatively slow and heavy.
They have a low penetrating power.
7
8. CONT…
You can stop them with just a sheet of
paper
:- because they have a large charge alpha
particle ionize other atom strongly.
Alpha decay occurs in very heavy element
e.g :- Radium and uranium
8
9. BETA PARTICLE
Beta particle have a charge of -1.
the means that beta particle are the same as an
electron.
We can write them as because they are the same
as electron
This means that when a nucleus emit a beta particle
:-
The atomic mass unchanged.
The atomic number increase by 1.
9
10. CONT..
They are fast and light.
Beta particle have a medium penitrating
power.
They are stopped by a sheet of
alumminium e.g :- phosphorus 32.
10
11. GAMMA RAYS
Gamma rays are waves not particle.
This means that they have no mass and no
charge.
In gamma decay:-
Atomic number unchanged
Atomic mass unchanged
Gamma ray have a high penetrating power.
11
12. CONT..
It take a thick sheet of metal such as lead to
reduce them.
Gamma rays do not directly ionize other
atoms
We do not find pure gamma source. Gamma
ray are emitted along with alpha and beta
particle.
12
13. BIOLOGICAL EFFECT OF RADIATION
Radiation have dangerous effect on biological system.
Locally induced ionization promotes a number of irreversible
change in living cell.
These change can be noticed after a short period of time or
may take year to develop.
As in case of genetic change the effect can be seen in
subsequent generation.
It must be assumed that all effect of radiation on living cell are
harmful.
There is no threshold level for the onset of there effect.
13
