Abstract:
Developing nanoparticulate delivery systems
that will allow easy movement and localization
of a drug to the target tissue and provide more
controlled release of the drug in vivo is a challenge in
nanomedicine. The aim of this study was to evaluate
the biodistribution of poly(D,L-lactide-co-glycolide)
(PLGA) nanoparticles containing samarium-153
oxide ([153Sm]Sm2O3) in vivo to prove that orally
administered nanoparticles alter the biodistribution of
a drug. These were then activated in a nuclear reactor
to produce radioactive 153Sm-loaded-PLGA nanoparticles.
The nanoparticles were characterized for size,
zeta potential, and morphology. The nanoparticles
were orally and intravenously (IV) administered to
rats in order to trace their uptake through imaging and biodistribution studies. The 153Sm-loaded-PLGA
nanoparticles had an average size of 281 ± 6.3 nm
and a PDI average of 0.22. The zeta potential ranged
between 5 and 20 mV. The [153Sm]Sm2O3 loaded
PLGA nanoparticles, orally administered were distributed
to most organs at low levels, indicating that
there was absorption of nanoparticles. While the IV
injected [153Sm]Sm2O3-loaded PLGA nanoparticles
exhibited the highest localization of nanoparticles in
the spleen (8.63 %ID/g) and liver (3.07 %ID/g),
confirming that nanoparticles are rapidly removed
from the blood by the RES, leading to rapid uptake in
the liver and spleen. From the biodistribution data
obtained, it is clear that polymeric nanoscale delivery
systems would be suitable for improving permeability
and thus the bioavailability of therapeutic compounds.