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E u r o S c i C o n C o n f e r e n c e o n
Nanotechnology &
Smart Materials
Nano Research & Applications
ISSN 2471-9838
O c t o b e r 0 4 - 0 6 , 2 0 1 8
Am s t e r d a m , N e t h e r l a n d s
Nanotechnology & Smart Materials 2018
Page 62
I
norder to create a clinically useful nanoparticle based treatment, it is necessary to
functionalise the surface of the nanoparticles. Poly ethylene glycol (PEG) is often
added to stop aggregation in-vivo and to prolong the circulation time by inhibiting
any undesired immune responses. Other groups such as antibodies can be added
to target nanoparticles to tumours, while peptides can be used to enhance cell
uptake and induce endosomal escape. Finally therapeutic payloads such as drugs
can also be attached to the nanoparticle surface. In the case of gold nanoparticles
(AuNPs), thiol chemistry is frequently used to tether the various groups to the
surface and two different attachment arrangements are possible. Firstly, all the
groups can be attached directly to the AuNP surface creating a mixed monolayer
arrangement or the biologically active groups can be attached via a linker unit such
as PEG. In this case, one end of the PEG is attached to the AuNP surface with
the biologically active group reacted with the free end. This linker arrangement
has the potential benefits of permitting higher loading levels, and should allow
for improved biological availability, as the biologically active groups are freely
available on the outside of the functionalised nanoparticles. We report that the
attaching H5WYG, an internalisation and endosomal escape peptide to ~15nm
AuNPs via a PEG linker rather than using a mixed monolayer arrangement results
in greater levels of cell uptake and enhanced radiosensitisation behaviour. We also
report on the influence of pH on the attachment of peptides to AuNPs using thiol
chemistry, investigate the low termstability of functionalised AuNPs, and highlight
some of our published animal data on the radiosensitisation potential of peptide
modified AuNPs.
Biography
D Dixon has received his PhD in Polymer Science from
Queen’s University Belfast in 2000 and is currently, serving as
a Senior Lecturer in Nanotechnology, at Ulster University in
Northern Ireland. His work is focused on functionalised gold
nanoparticles for applications in cancer treatment. He has
published around 50 papers.
Mixed monolayer and PEG linker
functionalised gold nanoparticles
D Dixon
1
, J Coulter
2
and C Dooley
1
1
Ulster University, UK
2
Queen’s University Belfast, UK
D Dixon et al., Nano Res Appl Volume:4
DOI: 10.21767/2471-9838-C6-024