The new 'Buy' tab has Au/Ag Plasmonic Hybrid NP fo

The new 'Buy' tab has Au/Ag Plasmonic Hybrid NP for sale.
I was curious about their use and found a 2008 white paper using them for spectroscopy. I have highlighted some uses in bold.

Novel Au/Ag Hybrid Device for Electrochemical SE(R)R
Spectroscopy in a Wide Potential and Spectral Range

https://www.unicat.tu-berlin.de/fileadmin/use...02934u.pdf

In summary, we have demonstrated that the novel Au-Ag
hybrid device developed in this work is suitable for SE(R)R
spectroscopy in the entire visible spectral region . Because
of an efficient transfer of plasmon excitation from the Ag to
the Au coating, the magnitude of the enhancement is
comparable to that for pure Ag systems while displaying the
electrochemical stability of gold. These properties expand
the perspectives of applying SER-spectroscopic techniques,
due to the better biocompatibility of Au and its significantly
higher importance in heterogeneous catalysis as compared
to Ag. These applications may include more sensitive
approaches in detecting and identifying biomolecules in
analytic assays by combining the molecular (pre)resonance
and surface enhancement effects upon excitation in the violet
region. This improved sensitivity of the hybrid devices may
also allow for monitoring catalytic processes in situ with and
without electrochemical control . Finally, these SER spectroscopic
applications are not restricted to stationary measurements
but may also be extended to the time-resolved
domain to probe the dynamics of interfacial reactions , as
already established for Ag electrodes.