Block Copolymer Brush Layer-Templated Gold Nanoparticles on Nanofibers for Surface-Enhanced Raman Scattering Optophysiology.
ACS Appl. Mater. Interfaces. 2019-01-07; 11(4): 4373-4384
DOI: 10.1021/acsami.8b19161
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Zhu H, Lussier F, Ducrot C, Bourque MJ, Spatz JP(1)(2), Cui W(3), Yu L(3), Peng W(3), Trudeau LÉ, Bazuin CG, Masson JF.
Author information:
(1)Department of Cellular Biophysics , Max Planck Institute for Medical Research
, Jahnstrasse 29 , D-69120 Heidelberg , Germany.
(2)Department of Biophysical Chemistry , University of Heidelberg , INF 253 ,
D-69120 Heidelberg , Germany.
(3)Department of Physics and Optoelectronic Engineering , Dalian University of
Technology , Dalian 116024 , China.
A nanothin block copolymer (BCP) brush-layer film adsorbed on glass nanofibers is
shown to address the long-standing challenge of forming a template for the
deposition of dense and well-dispersed nanoparticles on highly curved surfaces,
allowing the development of an improved nanosensor for neurotransmitters. We
employed a polystyrene- block-poly(4-vinylpyridine) BCP and plasmonic gold
nanoparticles (AuNPs) of 52 nm in diameter for the fabrication of the nanosensor
on pulled fibers with diameters down to 200 nm. The method is simple, using only
solution processes and a plasma cleaning step. The templating of the AuNPs on the
nanofiber surprisingly gave rise to more than 1 order of magnitude improvement in
the surface-enhanced Raman scattering (SERS) performance for 4-mercaptobenzoic
acid compared to the same AuNPs aggregated on identical fibers without the use of
a template. We hypothesize that a wavelength-scale lens formed by the nanofiber
contributes to enhancing the SERS performance to the extent that it can melt the
glass nanofiber under moderate laser power. We then show the capability of this
nanosensor to detect the corelease of the neurotransmitters dopamine and
glutamate from living mouse brain dopaminergic neurons with a sensitivity 1 order
of magnitude greater than with aggregated AuNPs. The simplicity of fabrication
and the far superior performance of the BCP-templated nanofiber demonstrates the
potential of this method to efficiently pattern nanoparticles on highly curved
surfaces and its application as molecular nanosensors for cell physiology.