SERS monitoring of photoinduced-enhanced oxidative stress amplifier on Au@carbon dots for tumor catalytic therapy

Abstract

Currently, artificial enzymes-based photodynamic therapy (PDT) is attractive due to its efficient capacity to change the immunosuppressive tumor microenvironment (TME). It is of great significance to study the therapeutic mechanism of novel artificial enzymes in TME through a monitoring strategy and improve the therapeutic effect. In this study, Au@carbon dots (Au@CDs) nanohybrids with a core-shell structure are synthesized, which not only exhibit tunable enzyme-mimicking activity under near-infrared (NIR) light, but also excellent surface-enhanced Raman scattering (SERS) properties. Therefore, Au@CDs show a good capability for monitoring NIR-photoinduced peroxidase-like catalytic processes via a SERS strategy in tumor. Moreover, the Au@CDs deplete glutathione with the cascade catalyzed reactions, thus elevating intratumor oxidative stress amplifying the reactive oxygen species damage based on the NIR-photoinduced enhanced peroxidase and glutathione oxidase-like activities, showing excellent and fast PDT therapeutic effect promoted by photothermal property in 3 min, finally leading to apoptosis in cancer cells. Through SERS monitoring, it is further found that after removing the NIR light source for 33 min, the reactive oxygen species (ROS) activity of the TME is counteracted and eliminated due to the presence of glutathione. This work presents a guidance to rationally design of artificial enzyme for ROS-involved therapeutic strategies and a new spectroscopic tool to evaluate the tumor catalytic therapy.

Calcination-controlled performance optimization of iron–vanadium bimetallic oxide nanoparticles for synergistic tumor therapy

“…36,37 The ideal photothermal reagent should have a great near-infrared light absorption capacity, strong photothermal conversion efficiency, and great biocompatibility. 38–40 These results revealed that FVO–Ar NPs had a good photothermal effect, indicating that they could be used as an excellent reagent for PTT in the NIR biological window.…”

Spotting the driving forces for SERS of two-dimensional nanomaterials

“…12,13 The preeminent SERS sensitivity enables noble metal substrates to be widely used in sensing, biomedical imaging, environmental monitoring and catalysis, etc. [14][15][16][17][18] Afterwards, the majority of semiconductor-enhanced Raman scattering is confirmed to involve a charge transfer (CT) process between the substrate and target molecules, which opens up a new way for exploring the chemical mechanism (CM) of SERS. 19,20 The CM effect, responsible for the interfacial CT interaction, endows the semiconductor SERS substrates with unique applications in chemical process observation, photovoltaic efficiency prediction, surface science investigation, etc.…”

Two-photon isomerization properties of donor–acceptor Stenhouse adducts

“…1 Such approaches have also served to photo-activate polymerization reactions, 2 and to induce the function of catalysts. 3,4 In these applications, photoinduced isomerization reactions are among the most successful methods to achieve such goals. 5,6 Several of the mentioned technologies require actuators that can be photoconverted in a highly localized volume.…”