The characteristics, biodistribution, magnetic resonance imaging and biodegradability of superparamagnetic core-shell nanoparticles.
An efficient contrast agent for magnetic resonance imaging (MRI) is essential to enhance the detection and characterization of lesions within the body. In this study, we described the development of biodegradable nanoparticles with a core-shell structure to formulate superparamagnetic iron oxide (CSNP-SPIO) for MRI. The developed nanoparticles were composed of a hydrophobic PLGA core and a positively-charged glycol chitosan shell. The results obtained by transmission electron microscopy, energy dispersive X-ray analysis, electron energy loss spectroscopy, and X-ray diffraction measurement confirmed that the prepared nanoparticles had a core-shell structure with SPIO in their core area. No aggregation of nanoparticles was observed during storage in water, as a result of the electrostatic repulsion between the positively-charged nanoparticles. The magnetic properties of nanoparticles were examined by a vibrating sample magnetometer and a superconducting quantum interference device; the results showed that the superparamagnetism of SPIO was preserved after the CSNP-SPIO formulation. In tracking their cellular internalization pathway, we found that CSNP-SPIO accumulated in lysosomes. In the biodistribution study, a high level of radioactivity was observed in the liver shortly after administration of the (99m)Tc-labeled CSNP-SPIO intravenously. Once taken up by the liver cells, the liver turned dark on T(2)* images. Following cellular internalization, CSNP-SPIO were broken down gradually; therefore, with time increasing, a significant decrease in the darkness of the liver on T(2)* images was found. The aforementioned results indicate that the developed CSNP-SPIO can serve as an efficient MRI contrast agent and could be degraded after serving their imaging function.
Lee
Po-Wei
PW
Department of Chemical Engineering, National Tsing Hua University, Hsinchu, Taiwan, ROC.
Hsu
Sheng-Hsiang
SH
Wang
Jiun-Jie
JJ
Tsai
Jin-Sheng
JS
Lin
Kun-Ju
KJ
Wey
Shiaw-Pyng
SP
Chen
Fu-Rong
FR
Lai
Chih-Huang
CH
Yen
Tzu-Chen
TC
Sung
Hsing-Wen
HW
D000818:Animals; D003287:Contrast Media / Q000737:chemistry* / Q000493:pharmacokinetics*; D005290:Ferric Compounds / Q000737:chemistry / Q000493:pharmacokinetics*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008422:Materials Testing; D053758:Nanoparticles / Q000737:chemistry*; D009928:Organ Specificity; D051381:Rats; D017207:Rats, Sprague-Dawley; D014018:Tissue Distribution
D003287:Contrast Media; D005290:Ferric Compounds; C000499:ferric oxide