Mo₂C‐Derived Polyoxometalate for NIR‐II Photoacoustic Imaging‐Guided Chemodynamic/Photothermal Synergistic Therapy

Abstract

To overcome the current limitations of chemodynamic therapy (CDT), a Mo2C‐derived polyoxometalate (POM) is readily synthesized as a new CDT agent. It permits synergistic chemodynamic and photothermal therapy operating in the second near‐infrared (NIR‐II) biological transparent window for deep tissue penetration. POM aggregated in an acidic tumor micro‐environment (TME) whereby enables specific tumor targeting. In addition to the strong ability to produce singlet oxygen (1O2) presumably via Russell mechanism, its excellent photothermal conversion enhances the CDT effect, offers additional tumor ablation modality, and permits NIR‐II photoacoustic imaging. Benefitting from the reversible redox property of molybdenum, the theranostics based on POM can escape from the antioxidant defense system. Moreover, combining the specific responsiveness to TME and localized laser irradiation, side‐effects shall be largely avoided.

An All‐Round Athlete on the Track of Phototheranostics: Subtly Regulating the Balance between Radiative and Nonradiative Decays for Multimodal Imaging‐Guided Synergistic Therapy

“…Additionally, tumor-selective delivery and irradiation site-specific phototheraputic effect of TSSI NPs could hopefully avoid the heat-induced damage on healthy organs/cells. [43] Following confirmation of their trimodal (NIR-II FLI-PAI-PTI) imaging ability, we assessed the in vivo tumoricidal activity of TSSI NPs using BALB/c nude mice bearing 4T1 xenograft tumors through systemic administration, during which only a single injection was carried out, followed by just once NIR irradiation (660 nm, 0.3 W cm −2 , 10 min) at 12 h postinjection. To our excitement, almost all the solid tumors of mice treated with TSSI NPs plus NIR irradiation were eliminated with scarcely any visible tumor observed at as early as day 3 after treatment ( Figure 3C).…”

Light: A Magical Tool for Controlled Drug Delivery

“…[128] Imaging-guided synergistic photothermal therapy provides a novel way to construct precision nanotheranostic agents. A number of multifunctional composite metal nanohybrids have been studied as potential nanoagents for imaging-guided synergistic photothermal therapy with diverse therapeutic and diagnostic payloads, including FePS 3 nanosheets with excellent photothermal conversion activity enabling chemodynamic therapy and hyperthermia effect for cancer therapy, [134] carbon-encapsulated FeCo nanomaterials as magnetic imaging tracers with magnetothermal and photothermal capablities, [135] zirconium-ferriporphyrin MOF nanotransducer complexed with heat shock protein 70 siRNA for computed tomography, photothermal, and photoacoustic trimode imaging modalities-guided combined gene and photothermal-photodynamic therapy for efficient cancer elimination, [136] FePt/MoS 2 nanomaterials with synergistic photothermal-chemotherapy for improving tumor immunotherapy, [137] Mo 2 C-derived polyoxometalate as a chemodynamic therapy agent, [138] functionalized MoTe 2 nanosheets with PEG-cyclic RGD and DOX for combined photothermal and chemotherapy, [139] Cu-based Fenton like agent copper(I) phosphide (Cu 3 P) nanocrystal for magnetic resonance imaging-based cancer chemodynamic/ photothermal combination therapy, [140] copper-palladium alloy nanocrystals for multispectral optoacoustic tomography (MSOT) imaging guided photothermal chemotherapy, [141] PdH nanohydride for combinational hydrogen releasing-triggered hydrogen-photothermal treatment, [142] polyelectrolyte-multilayer-coated Cs x WO 3 for computerized tomography (CT)/ photo acoustic bimodal imaging-based cancer photodynamic/ photothermal therapy, [143] tungsten-based polyoxometalate nanoclusters for efficient photothermal and anti-inflammatory treatment, [144] vanadium carbide nanosheets with enhanced NIR photothermal performance, [145] Bi/phthalocyanine manganese photo sensitizer nanocomposites with high magnetic resonance and CT imaging performance for photothermal and photodynamic therapy, [146] supramolecular photo thermal nanodrugs BSA-pheophorbide a-Mn 2+ nanoparticle with heating-enhanced photothermal effects, [147] the MOF Hf-UiO-66 archetype structure incorporated with photoactive tetratopic chlorin ligands for multimodal CT/thermal/photoacoustic imaging-guided photothermal-photodynamic anticancer therapy. [148] An interesting work presented a core-shell nanotheranostic agents, that is, the FeCo core nanomaterials and bore graphitic carbon shells grafted with PEG, providing not only the high magnetic particle imaging signal intensity and the photoacoustic imaging function, but also photothermal and magnetothermal properties for efficient tumor elimination in mice.…”

Polyoxometalate Composites in Cancer Therapy and Diagnostics

“…Differently, Liu et al prepared a polyoxomolybdate by one‐pot oxidation reaction of bulk Mo 2 C powder. Similarly to the described for the Keggin anion [PMo 12 O 40 ] 3– , the prepared POM exhibits an acidic‐induced aggregation that allows its enhanced retention in the tumour tissues as well as the ability to be reduced under the tumour reductive environment (namely in the presence of glutathione).…”