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hydrolysis-triggered aqueous–organic phase transfer suggests
that the esterase hydrolysis of ligands could induce the inter-
nalization of AuNPs into cells. Our finding regarding the advan-
tages of ester ligands will be applicable to deliver the various
functional nanoparticles into cells.
This work was supported by KAKENHI 22655050: Grant-in-Aid
for Challenging Exploratory Research. Dr S. Sekiguchi appreciates
the financial support provided by JSPS. The authors also thank Ms
T. Kikitsu of the Material Characterization Team (RIKEN) for TEM
image analysis and Ms K. Otsuki, Mr M. Usui, and Ms A. Abe of the
Mass Spectrometry Service (RIKEN) for MALDI-TOFMS analysis.
Notes and references
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Fig. 4 Ultra-thin section image of HeLa cells observed by TEM. HeLa cells
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cytosol. Scale bar: 200 nm.
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that the main internalization pathway is endocytotic uptake,
although some C2-ester-AuNPs were internalized into cells via
membrane permeation. Fig. S3 (ESI†) shows a time course of
TEM images of HeLa cells after incubation with C2-ester-AuNPs.
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hypothesis to rationalize the preferential uptake of ester type ligands.
Both hydrophobic ester and ether terminal moieties have high
¨
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´ ´
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Chem. Commun., 2014, 50, 1265--1267 | 1267