High-contrast in vivo visualization of microvessels using novel FeCo/GC magnetic nanocrystals.
FeCo-graphitic carbon shell nanocrystals are a novel MRI contrast agent with unprecedented high per-metal-atom-basis relaxivity (r(1) = 97 mM(-1) sec(-1), r(2) = 400 mM(-1) sec(-1)) and multifunctional capabilities. While the conventional gadolinium-based contrast-enhanced angiographic magnetic MRI has proven useful for diagnosis of vascular diseases, its short circulation time and relatively low sensitivity render high-resolution MRI of morphologically small vascular structures such as those involved in collateral, arteriogenic, and angiogenic vessel formation challenging. Here, by combining FeCo-graphitic carbon shell nanocrystals with high-resolution MRI technique, we demonstrate that such microvessels down to approximately 100 mum can be monitored in high contrast and noninvasively using a conventional 1.5-T clinical MRI system, achieving a diagnostic imaging standard approximating that of the more invasive X-ray angiography. Preliminary in vitro and in vivo toxicity study results also show no sign of toxicity.
Department of Electrical Engineering, Stanford University, Stanford, California 94305-5080, USA.
Jin Hyung
JH
Lee
Sarah P
SP
Sherlock
Masahiro
M
Terashima
Hisanori
H
Kosuge
Yoriyasu
Y
Suzuki
Andrew
A
Goodwin
Joshua
J
Robinson
Won Seok
WS
Seo
Zhuang
Z
Liu
Richard
R
Luong
Michael V
MV
McConnell
Dwight G
DG
Nishimura
Hongjie
H
Dai
D000818:Animals; D003035:Cobalt / Q000737:chemistry; D003287:Contrast Media / Q000138:chemical synthesis*; D052203:Ferrosoferric Oxide / Q000138:chemical synthesis*; D006108:Graphite / Q000737:chemistry; D007089:Image Enhancement / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D055806:Microvessels / Q000033:anatomy & histology*; D011817:Rabbits
D003287:Contrast Media; D003035:Cobalt; D006108:Graphite; D052203:Ferrosoferric Oxide