Particle size analysis: 90Y and 99mTc-labelled colloids.
Colloidal particle size is an important characteristic to consider when choosing a radiopharmaceutical for diagnosis and therapeutic purposes in nuclear medicine. Photon correlation spectroscopy (PCS) and transmission electron microscopy (TEM) were used to determine the particle-size distribution of (90)Y- and (99m)Tc-labelled antimony trisulfide (Sb(2)S(3)) and tin colloids (Sn-colloid). (90)Y-Sb(2)S(3) and (99m)Tc-Sb(2)S(3) were found to have a diameter of 28.92 +/- 0.14 and 35.61 +/- 0.11 nm, respectively, by PCS. By TEM, (90)Y-Sb(2)S(3) particles were measured to be 14.33 +/- 0.09 nm. (90)Y-labelled Sn colloid were found to exist with a d(v(max1)) of 805 nm and a d(v(max2)) of 2590 nm, by PCS, whereas (99m)Tc-Sn colloid was shown to have more than 80% of radioactive particles of approximately 910 nm by PCS. For (90)Y-labelled Sb(2)S(3) and Sn colloid, a comparison of TEM and PCS indicates that these techniques found significantly different mean diameters. TEM has an excellent resolution necessary for radiocolloid particle-sizing analysis, and it is a desirable size-measuring technique because it is more reliable than PCS.
Janković
D
D
Vinca Institute of Nuclear Sciences, 11000 Belgrade, Serbia. drinaj@vin.bg.ac.yu
Maksin
T
T
Djokić
D
D
Milonjić
S
S
Nikolić
N
N
Mirković
M
M
Vranjes-Djurić
S
S
D003102:Colloids; D046529:Microscopy, Electron, Transmission / Q000379:methods*; D053758:Nanoparticles / Q000648:ultrastructure*; D010316:Particle Size
D003102:Colloids