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the vasculature, the various shapes of
nanoparticles experience distinct hydrody-
namic forces. Nonspherical nanoparticles
readily torque and tumble, so they exhibit
a stronger tendency to move towards the
vessel than do spherical nanoparticles.
Furthermore, spherical particles have also
been documented as possessing faster
macrophage internalization rates than
elongated particles because spherical par-
ticles travel fast towards the nucleus and
exhibit hexagonal packing in the cell,
compared with elongated particles that
migrate slowly.
[9,10]
Moreover, the ability of
antibody-conjugated rod-shaped particles
to adhere to the target cell surface is more
effective.
[11]
The filomicelles have also
been observed to exhibit a longer circula-
tion time than the spherical micelles.
[12]
Overall, the shape of the nanoparticles is a
key factor influencing the circulation time
and tumor targeting ability, which directly
affect the therapeutic efficacy.
2D graphene-based materials (such as graphene oxide (GO),
reduced graphene oxide (rGO) and GO-composites) exhibiting
a high photoabsorbance and a large specific surface area with
abundant functional groups are an excellent candidate for
cargo transporting and particle decoration for drug delivery and
enhanced tumor therapy.
[13–15]
Despite recent advancements
in the drug delivery of GO, the therapeutic cargo is typically
adsorbed on or tethered to the surface of GO, leading to an
undesired release and other side effects. To address this issue,
GO has been developed to serve as a thin shell to fully conceal
large amounts of therapeutic cargo in one compact capsule.
For example, GO has been deposited on a microcapsule com-
posed of gold nanoparticles and poly(lactic acid) via layer-by-
layer assembly and displays a high cancer killing efficacy upon
NIR treatment.
[16]
A double emulsion of protein–graphene–pro-
tein (PGP) capsule has also been made from an amphiphilic
protein and rGO, to encapsulate large amounts of anticancer
drugs. Applying NIR irradiation, PGP capsules widely spread
anticancer drugs to eradicate tumor cells in the light-treating
area, as well as the light-omitted tumor cells.
[17]
In addition
to drug encapsulation, coating a GO layer on a gold rod also
amplifies the photoacoustic property and enhanced photo-
thermal stability of the gold.
[18,19]
Moreover, another type of
Dual-Targeted Photopenetrative Delivery of Multiple
Micelles/Hydrophobic Drugs by a Nanopea for Enhanced
Tumor Therapy
Chien-Ting Lin, I-Chieh Lin, Shou-Yuan Sung, Yu-Lin Su, Yu-Fen Huang,
Chi-Shiun Chiang, and Shang-Hsiu Hu*
A photoresponsive pea-like capsule (nanopea) that also represents a photo-
thermal agent is constructed by wrapping multiple polymer micelles (poly-
vinyl alcohol, PVA) in reduced graphene oxide nanoshells through a double
emulsion approach. Resulting nanopeas can transport multiple PVA micelles
containing the fully concealed hydrophobic drug docetaxel (DTX) which can
be later released by a near-infrared photoactuation trigger. Through inte-
grating the rod-shaped adhesion and lactoferrin (Lf ) targeting, the nanopea
enhances both uptake by cancer cellc in vitro and particle accumulation at
tumor in vivo. A photopenetrative delivery of micelles/DTX to the tumor
site is actuated by NIR irradiation which ruptures the nanopeas as well as
releases nanosized micelles/DTX. This trigger also results in thermal damage
to the tumor and increases the micelles/DTX permeability, facilitating drug
penetration into the deep tumor far from blood vessels for thermal chemo-
therapy. This nanopea with the capability of imaging, enhanced tumor accu-
mulation, NIR-triggered tumor penetration, and hyperthermia ablation for
photothermal chemotherapy boosts tumor treatment and shows potential for
use in other biological applications.
DOI: 10.1002/adfm.201600498
Dr. C.-T. Lin, Dr. I.-C. Lin, Dr. S.-Y. Sung, Dr. Y.-L. Su,
Prof. Y.-F. Huang, Prof. C.-S. Chiang, Prof. S.-H. Hu
Department of Biomedical Engineering
and Environmental Sciences
National Tsing Hua University
Hsinchu 300, Taiwan
E-mail: shhu@mx.nthu.edu.tw
1. Introduction
Compact nanoparticles with multiple functions are currently
of considerable interest for use in biomedical applications.
[1]
By tuning their size and surface properties, the particles can
selectively interact with specific biomolecules, which are found
either in the cytoplasm or on the cell membrane, and transport
cargo into the cell by crossing the plasma membrane.
[2]
There-
fore, a variety of versatile nanoparticles with distinct organic
and inorganic compositions (such as carbon-based, metallic and
polymeric nanoparticles) possessing unique physicochemical
features and sophisticated structures has been developed.
[3–6]
Remarkably, particle shape plays a significant role in biodistri-
bution and cellular internalization.
[7,8]
While flowing through
Adv. Funct. Mater. 2016, 26, 4169–4179
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