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is very rapid as evidenced by a bladder signal at 7 minutes
post-IV and is completed at 30 minutes. No unspecific uptake
such as lung or RES uptake is observed (no signal in liver, bone
marrow, spleen) leading to complete elimination of all injected
NP@9@Alexa647 within 24 hours post-IV.
Previously6b,15 and currently reported studies clearly high-
light that the dendritic organic coating impacts the aggregation
state of the nano-objects, thus influencing the bioelimination
speed and importance of the hepatobiliary versus urinary elimi-
nation pathway: NPs covered with small dendrons (this study) are
more rapidly and completely eliminated within 24 hours post-IV,
predominantly by urinary elimination.
We thank the CNRS, UDS and ECPM for financial support.
This work was also supported by the National Research Agency
through fellowships to C. Ghobril (ANR EMERGENT) and
Fig. 2 In vivo whole body (A1, B1 and B2) and ex vivo organs (A2 and B3) optical
images of NP@9@Alexa647 performed at 7 minutes (A1), 20 minutes (B1), 30 minutes
(A2) and 24 hours (B2 and B3) post iv injection. The yellow square includes ex vivo
organ images of control mouse imaged with the same parameters [1 = lungs,
2 = urines, 3 = heart, 4 = spleen, 5 = kidney, 6 = liver, 7 = brain, 8 = digestive tract,
9 = bone sample, 10 = skin sample, 11 = blood sample, 12 = muscle sample]. Fine
arrows indicate bladder signal, large arrow indicates liver signal.
´
G. Popa (ANR NANOTHER) and by the Region Alsace (fellowship
to A. Parat).
Notes and references
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c
9160 Chem. Commun., 2013, 49, 9158--9160
This journal is The Royal Society of Chemistry 2013