With the rapid development of nanotechnology during the last decades, the ability to detect
and control individual objects at the nanoscale has enabled to deal with complex biomedical
challenges. In cancer imaging, novel nanoparticles (NPs) offer promising potential to identify
single cancer cells and precisely label larger areas ...
With the rapid development of nanotechnology during the last decades, the ability to detect
and control individual objects at the nanoscale has enabled to deal with complex biomedical
challenges. In cancer imaging, novel nanoparticles (NPs) offer promising potential to identify
single cancer cells and precisely label larger areas of cancer tissues. Herein, a new class of
size tunable core-shell composite (Au-SiO2-WO3) nanoparticles is reported. These
nanoparticles display an easily improvable ∼ 103
surface-enhanced Raman scattering (SERS)
enhancement factor (EF) with a double Au shell for dried samples over Si wafers and several
orders of magnitude for liquid samples. WO3 core nanoparticles of 20-50 nm in diameter are
sheathed by an intermediate 10-60 nm silica layer, produced by following the Stöber basedprocess and Turkevich method, followed by a 5-20 nm thick Au outer shell. By attaching 4-
mercaptobenzoic acid (4-MBA) molecules as Raman reporters to the Au, high-resolution
Raman maps which pinpoint the nanoparticles’ location are obtained. Our preliminary results
confirm their advantageous SERS properties for single-molecule detection, significant cell
viability after 24 h and in vitro cell imaging using coherent anti-stokes Raman scattering
(CARS). Our long-term objective is to measure SERS nanoparticles in vivo using NearInfrared light.