A simple process, rich information,
and intelligent response are
the goals pursued by cancer diagnosis and treatment. Herein, we developed
a core–shell plasmonic nanomaterial (Au@MnO2-DNA),
which consisted of a AuNP core with an outer shell MnO2 nanosheet decorated with fluorophore modified DNA, to achieve the
aforementioned aims. On the basis of the unique optical properties
of plasmonic nanoparticles and the oxidability of the shell MnO2, scattering signal and fluorescence (FL) signal changes were
both related to the expression level of glutathione (GSH), for which
a dual-mode imaging analysis was successfully achieved on single optical
microscope equipment with one-key switching. Meanwhile, the product
of Mn2+ from the reaction between MnO2 and GSH
not only served as a smart chemodynamic agent to initiate Fenton-like
reaction for achieving chemodynamic therapy (CDT) of cancer cells
but also relieved the side effect of intracellular GSH in cancer therapy.
Therefore, the core–shell plasmonic nanomaterials with dual
modal switching features and diagnostic properties act as excellent
probes for achieving bioanalysis of aberrant levels of intracellular
GSH and simultaneously activating the CDT of cancer cells based on
the in situ reactions in cancer cells.