Radiopharmacy Flashcards
What is radio pharmacy
Use of radioactivity in clinical diagnosis and treatment
Radio pharmaceuticals
Radioactive diagnostic or therapeutic pharmaceuticals that targets a specific organ or system by virtue of its molecular design
What affects the stability of the nucleus
Relative amount of neutrons and protons
Nucleonic binding energy
Mass defect
Alpha particle
Helium nucleus (2 protons and 2 neutrons and no electrons)
2+
Beta minus particle
Electron
-1
Beta plus particle
Anti electron / positron
1+
Gamma and x rays
Electro magnetic radiation
Gamma rays occurs when nucleus is meta stable/unstable
X-rays comes from electrons
X-rays
Electron capture
Metastable
Nucleus is in an excited state above its ground state (isomeric)
Release of gamma energy allows nuclide/isotope to transform to ground state
Bremmstrahlung
Secondary radiation effect with beta radiation
Electrons are deflected by mass and charge of nucleus
Electrons lose speed
Excess energy is released as x rays
Effects of radioactivity on the body
Ionising radiation creates ion pairs and can cause localised heating- damage in tissues
Radioactive decay eq
Nt = N0 exp (-k x t)
T= time
N0= number of radioactive atoms at t=0
Half life eq
0.693/ k
How much bq is 1 curie
1 curie= 37 GBq
1GBq= 1,000,000,000Bq
Absorbed radioactive dose
Measure of how much energy from the radiation has been deposited in the body
Equivalent dose eq
Absorbed dose x radiation weighting factor
What is specific gamma ray constant
Relates the energy of the gamma ray and the distance between the source and the tissue to the effective dose received
When does the specific gamma ray constant increase and decrease
Increases with increasing gamma ray energy
Decreases with distance between source and target
Cyclotron
Charged particles acceleration in a circular path
Nuclear fission
Nucleus+ neutrons
Absorbed neutrons
Releasing two half size nuclides, neutrons and energy (splitting)
