Nanomedicine (Lond.) (Epub ahead of print) ISSN 1743-5889
part of
Research Article
10.2217/nnm.15.103 © 2015 Future Medicine Ltd
Aim: To investigate the influence of gold nanoparticle geometry on the biochemical
response of Calu-3 epithelial cells. Materials & methods: Spherical, triangular and
hexagonal gold nanoparticles (GNPs) were used. The GNP-cell interaction was assessed
via atomic absorption spectroscopy (AAS) and transmission electron microscopy
(TEM). The biochemical impact of GNPs was determined over 72 h at (0.0001–1 mg/
ml). Results: At 1 mg/ml, hexagonal GNPs reduced Calu-3 viability below 60%, showed
increased reactive oxygen species production and higher expression of proapoptotic
markers. A cell mass burden of 1:2:12 as well as number of GNPs per cell (2:1:3) was
observed for spherical:triangular:hexagonal GNPs. Conclusion: These findings do not
suggest a direct shape-toxicity effect. However, do highlight the contribution of shape
towards the GNP-cell interaction which impacts upon their intracellular number, mass
and volume dose.
Keywords: biocompatibility•caspases•Cathepsin-B•CD95(APO-1/Fas)•celldeath•gold
nanoparticles•lungepithelialcells•nanoparticleshape•nanotoxicology•reactiveoxygen
species
Due to their plasmonic properties, gold
nanoparticles (GNPs) have been proposed as
advantageous nanosized materials for use in
the various diagnostic and therapeutic appli-
cations, such as cell imaging, targeted drug
delivery, thermal ablation, phototherapy [1–7] .
To date, spherical GNPs have been proven as
one of the most biocompatible NP models for
biological-based applications [8–12] . Recently,
it has been reported that the specific shape
of GNPs can be exploited to advantageously
tune these nanomaterials for any biomedi-
cal application of choice [8,13] . Examples of
such alternatively shaped GNPs being pro-
duced include, amongst others, rods, trian-
gles, hexagons, prisms, urchins, cubes and
wires [11,14] . Triangular and hexagonal GNPs
have been specifically reported as promising
contrast agents for in vivo imaging applica-
tions in place of the commonly used spherical
GNPs [8,13,15] . The reason for this is the shift
of the optical resonance of these differently
shaped GNPs to the near-infrared region
of the spectrum, which allows for a greater
potential to penetrate deeper inside tissues
without photobleaching [5,13,16] .
Therefore, to envisage the use of these
alternatively shaped GNPs within any poten-
tial medical applications their biocompatibil-
ity must be realized. In this regard, increased
attention has recently been focused towards
their cellular interaction [17] . Although it is
well known that specific physicochemical
characteristics (e.g., size, surface chemistry)
of GNPs can indeed influence their cellular
uptake and accumulation [10,18] , the ability
for shape to play a significant role in their
interaction of GNPs with mammalian cells
in vitro is not fully understood. Many stud-
ies have undertaken investigations into how
differently shaped NPs may interact with, or
be internalized by mammalian cells [19] , yet
in order to fully comprehend the potential
of alternatively shaped GNPs for biomedical
applications, their biochemical impact must
also be considered [20] . However, understand-
Investigating the role of shape on the
biological impact of gold nanoparticles
in vitro
Furong Tian
‡,1,2
, Martin JD
Clift
‡,3
, Alan Casey
2
, Pablo
del Pino
4
, Beatriz Pelaz
5
,
João Conde
6
, Hugh J Byrne
2
,
Barbara Rothen-Rutishauser
3
,
Giovani Estrada
7
, Jesús M de
la Fuente
8
& Tobias Stoeger*
,1
1
ComprehensivePneumologyCentre,
InstituteofLungBiology&Disease,
HelmholtzZentrumMünchen,
Neuherberg,Germany
2
NanolabResearchCentre,FOCAS
ResearchInstitute,DublinInstituteof
Technology,CamdenRow,Dublin,
Ireland
3
BioNanomaterials,AdolpheMerkle
Institute,UniversityofFribourg,
Switzerland
4
CICbiomaGUNE,SanSebastian,Spain
5
FachbereichPhysik,PhilippsUniversität
Marburg,Marburg,Germany
6
MassachusettsInstituteofTechnology,
InstituteforMedicalEngineering
&Science,Harvard-MITDivisionfor
HealthSciences&Technology,E25–449
Cambridge,MA,USA
7
InstituteofBioinformatics,Helmholtz
ZentrumMünchen,Neuherberg,
Germany
8
InstitutodeCienciadeMaterialesde
AragonCSIC-UniversidaddeZaragoza,
Spain
*Authorforcorrespondence:
tobias.stoeger@helmholtz-muenchen.de
‡
Authorscontributedequally
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