Bimetallic Cu@Ru Core-Shell Structures with Ligand Effects for Endo-Exogenous Stimulation-Mediated Dynamic Oncotherapy.

Dynamic therapies, which induce reactive oxygen species (ROS) production in situ through endogenous and exogenous stimulation, are emerging as attractive options for tumor treatment. However, the complexity of the tumor substantially limits the efficacy of individual stimulus-triggered dynamic therapy. Herein, bimetallic copper and ruthenium (Cu@Ru) core-shell nanoparticles are applied for endo-exogenous stimulation-triggered dynamic therapy. The electronic structure of Cu@Ru is regulated through the ligand effects to improve the adsorption level for small molecules, such as water and oxygen. The core-shell heterojunction interface can rapidly separate electron-hole pairs generated by ultrasound and light stimulation, which initiate reactions with adsorbed small molecules, thus enhancing ROS generation. This synergistically complements tumor treatment together with ROS from endogenous stimulation. In vitro and in vivo experiments demonstrate that Cu@Ru nanoparticles can induce tumor cell apoptosis and ferroptosis through generated ROS. This study provides a new paradigm for endo-exogenous stimulation-based synergistic tumor treatment.

Pseudopyrolysis of Metal-Organic Frameworks: A Synchronous Nucleation Mechanism to Synthesize Ultrafine Metal Compound Nanoparticles.

Metal-Organic frameworks (MOFs) are increasingly being investigated for the synthesis of carbon-supported metal-based ultrafine nanoparticles (UNPs). However, the collapse of the carbon framework and aggregation of metal particles in the pyrolysis process have severely hindered their stability and applications. Here, we report the synchronous nucleation pseudopyrolysis of MOFs to confine Fe/FeOx UNPs in intact porous carbon nanorods (IPCNs), revealed by in situ transmission electron microscopy experiments and ex situ structure analysis. The pseudopyrolysis mechanism enables strong physical and chemical confinement effects between UNPs and carbon by moderate thermal kinetics and abundant oxygen defects. Further, this strong confinement is greatly beneficial for subsequent chemical transformations to obtain different Fe-based UNPs and excellent electrochemical performance. As a proof of concept, the as-prepared FeSe UNPs in IPCNs show superior lithium storage performance with an ultrahigh and stable capacity of 815.1 mAh g-1 at 0.1 A g -1 and 379.7 mAh g-1 at 5 A g-1 for 1000 cycles.

Three Strategies in Engineering Nanomedicines for Tumor Microenvironment-Enabled Phototherapy.

Canonical phototherapeutics have several limitations, including a lack of tumor selectivity, nondiscriminatory phototoxicity, and tumor hypoxia aggravation. The tumor microenvironment (TME) is characterized by hypoxia, acidic pH, and high levels of H2 O2 , GSH, and proteases. To overcome the shortcomings of canonical phototherapy and achieve optimal theranostic effects with minimal side effects, unique TME characteristics are employed in the development of phototherapeutic nanomedicines. In this review, the effectiveness of three strategies for developing advanced phototherapeutics based on various TME characteristics is examined. The first strategy involves targeted delivery of phototherapeutics to tumors with the assistance of TME-induced nanoparticle disassembly or surface modification. The second strategy involves near-infrared absorption increase-induced phototherapy activation triggered by TME factors. The third strategy involves enhancing therapeutic efficacy by ameliorating TME. The functionalities, working principles, and significance of the three strategies for various applications are highlighted. Finally, possible challenges and future perspectives for further development are discussed.

Biodistribution, degradability and clearance of 2D materials for their biomedical applications.

Two-dimensional (2D) materials have evolved to be a class of rapidly advancing chemical entities in the biomedical field. Nevertheless, potential side effects and safety concerns severely limit their clinical translation. After administration, 2D materials cross multiple biological barriers and are distributed throughout the body. Only the portion that accumulates at the diseased sites exerts a therapeutic effect, whereas those distributed elsewhere may cause damage to healthy tissues and interference to normal physiological function of various organs. To achieve maximum therapeutic efficacy and minimum adverse effects simultaneously, the delivery of 2D materials must be targeted at diseased sites to reach therapeutic concentrations, and the materials must possess sufficient degradation and clearance rates to avoid long-term toxicity. Therefore, it is essential to understand the biodistribution and destiny of 2D materials in vivo. In this review, first, we provide a comprehensive picture of the strategies that are currently adopted for regulating the in vivo fate of 2D materials, including modulations of their size, surface properties, composition, and external stimuli. Second, we systematically review the biodistribution, degradation, and metabolism of several newly emerged 2D materials. Finally, we also discuss the development opportunities of 2D materials in the biomedical field and the challenges to be addressed.

Intracellular Mutual Amplification of Oxidative Stress and Inhibition Multidrug Resistance for Enhanced Sonodynamic/Chemodynamic/Chemo Therapy.

Emerging noninvasive treatments, such as sonodynamic therapy (SDT) and chemodynamic therapy (CDT), have developed as promising alternatives or supplements to traditional chemotherapy. However, their therapeutic effects are limited by the hypoxic environment of tumors. Here, a biodegradable nanocomposite-mesoporous zeolitic-imidazolate-framework@MnO2 /doxorubicin hydrochloride (mZMD) is developed, which achieves enhanced SDT/CDT/chemotherapy through promoting oxidative stress and overcoming the multidrug resistance. The mZMD decomposes under both ultrasound (US) irradiation and specific reactions in the tumor microenvironment (TME). The mZM composite structure reduces the recombination rate of e- and h+ to improve SDT. MnO2 not only oxidizes glutathione in tumor cells to enhance oxidative stress, but also converts the endogenic H2 O2 into O2 to improve the hypoxic TME, which enhances the effects of chemotherapy/SDT. Meanwhile, the generated Mn2+ catalyzes the endogenic H2 O2 into ·OH for CDT, and acts as magnetic resonance imaging agent to guide therapy. In addition, dissociated Zn2+ further breaks the redox balance of TME, and co-inhibits the expression of P-glycoprotein (P-gp) with generated ROS to overcome drug resistance. Thus, the as-prepared intelligent biodegradable mZMD provides an innovative strategy to enhance SDT/CDT/chemotherapy.

Boosting Charge Transfer Via Heterostructure Engineering of Ti2 CTx /Na2 Ti3 O7 Nanobelts Array for Superior Sodium Storage Performance.

The poor conductivity, inert charge transmission efficiency, and irreversible Na+ trapping of Na2 Ti3 O7 result in retardant electrons/ions transportation and deficient sodium-ion storage efficiency, leading to sluggish reaction kinetics. To address these issues, an urchin-like Ti2 CTx /Na2 Ti3 O7 (Ti2 C/NTO) heterostructure sphere consisting of Ti2 C/NTO heterostructure nanobelts array is developed via a facile one-step in situ hydrothermal strategy. The Ti2 C/NTO heterostructure can obviously decrease Na+ diffusion barriers and increase electronic conductivity to improve reaction kinetics due to the built-in electric field effect and high-quantity interface region. In addition, the urchin-like vertically aligned nanobelts can reduce the diffusion distance of electrons and ions, provide favored electrolyte infiltration, adapt large volume expansion, and mitigate the aggregation to maintain structural stability during cycles, further enhancing the reaction kinetics. Furthermore, the Ti2 C/NTO heterostructure can effectively suppress many unwanted side reactions between reactive surface sites of NTO and electrolyte as well as irreversible trapping of Na+ . As a result, systematic electrochemical investigations demonstrate that the Ti2 C/NTO heterostructure as an anode material for record sodium-ion storage delivers the highest reversible capacity, the best cycling stability with 0.0065% decay rate for 4500 cycles at 2.0 A g-1 , and excellent rate capability of 172.1 mAh g-1 at 10.0 A g-1 .

Programmable DNA Framework Sensors for In Situ Cell-Surface pH Analysis.

The availability of strategies for developing sensors with a defined responsiveness as well as the ability to working in a biological environment is critical to the fields of bioanalysis, nanomedicine, and nanorobotics. Herein, we developed programmable pH sensors by employing a tetrahedral DNA framework (TDF) as a robust structural skeleton for the sensors in biological working scenes and DNA i-motif structures as proton-recognition probes. The sensors' response midpoint and dynamic range can be fine-tuned by deliberately altering the i-motif's sequence composition or by combining different sensors, affording pH response windows that are consecutively distributed in the biologically relevant pH range of 5.0-7.5. This controllable tunability was successfully employed for in situ cell-surface pH analysis after anchoring the i-motif-TDF nanosensor on the cell surface via a two-step anchoring strategy, providing a useful platform for the diagnostics of diseases associated with extracellular pH variations.

Fast Modulation of Surface Amphiphobicity/Amphiphilicity via Bidirectional Substitution between Perfluorinated Surfactants and Polyanions throughout Pre-Assembled Polyelectrolyte Multilayers.

In the present work, we demonstrate a bidirectional substitution between perfluorooctanoate (PFO) surfactants and polyanions throughout the pre-assembled polyelectrolyte multilayers (PEMs) for a rapid modulation of surface wettability between amphiphobicity and amphiphilicity. Upon incubation of the PEMs made of alternating deposition of poly(diallyldimethylammonium) (PDDA) and poly(styrenesulfonate) (PSS) in PFO solutions at concentrations above or around its critical micelle concentration, the majority (ca. >75%) of PSS molecules throughout the PDDA/PSS PEMs can be substituted by PFO anions within 10 s, generating PFO-substituted PDDA/PSS (PFO-PDDA/PSS) films. This effective substitution of PSS polyanions in PDDA/PSS PEMs by PFO anions is suggested by the mechanism that the stability of PDDA/PFO complexes is higher than that of PDDA/PSS PEMs. Furthermore, PFO anions all the way through the PFO-PDDA/PSS films can be reversibly substituted by PSS polyanions, while the substitution efficiency depends on the ionic strength of the PSS solutions. The processes of bidirectional and reversible substitution between PFO anions and PSS polyanions throughout the PDDA/PSS films can be repeated at least 10 times accompanied with a negligible change in the film thickness and surface morphology. The surface wettability study reveals that the PFO-PDDA/PSS films are amphiphobic with water and oil contact angles (CAs) of 114 ± 2 and 64 ± 2°, respectively, while PSS-substituted PFO-(PDDA/PSS) films are amphiphilic with water and oil CAs of 6 ± 1 and 0°, respectively. These novelties of the films enable switchable surface wettability simply by dipping the PDDA/PSS film-coated objects into PFO solutions for 2 s or PSS solutions for 30 s.

Stabilizing Lithium-Sulfur Batteries through Control of Sulfur Aggregation and Polysulfide Dissolution.

Lithium-sulfur (Li-S) batteries are investigated intensively as a promising large-scale energy storage system owing to their high theoretical energy density. However, the application of Li-S batteries is prevented by a series of primary problems, including low electronic conductivity, volumetric fluctuation, poor loading of sulfur, and shuttle effect caused by soluble lithium polysulfides. Here, a novel composite structure of sulfur nanoparticles attached to porous-carbon nanotube (p-CNT) encapsulated by hollow MnO2 nanoflakes film to form p-CNT@Void@MnO2 /S composite structures is reported. Benefiting from p-CNTs and sponge-like MnO2 nanoflake film, p-CNT@Void@MnO2 /S provides highly efficient pathways for the fast electron/ion transfer, fixes sulfur and Li2 S aggregation efficiently, and prevents polysulfide dissolution during cycling. Besides, the additional void inside p-CNT@Void@MnO2 /S composite structure provides sufficient free space for the expansion of encapsulated sulfur nanoparticles. The special material composition and structural design of p-CNT@Void@MnO2 /S composite structure with a high sulfur content endow the composite high capacity, high Coulombic efficiency, and an excellent cycling stability. The capacity of p-CNT@Void@MnO2 /S electrode is ≈599.1 mA h g-1 for the fourth cycle and ≈526.1 mA h g-1 after 100 cycles, corresponding to a capacity retention of ≈87.8% at a high current density of 1.0 C.

Design and Functionalization of the NIR-Responsive Photothermal Semiconductor Nanomaterials for Cancer Theranostics.

Despite the development of medical technology, cancer still remains a great threat to the survival of people all over the world. Photothermal therapy (PTT) is a minimally invasive method for selective photothermal ablation of cancer cells without damages to normal cells. Recently, copper chalcogenide semiconductors have emerged as a promising photothermal agent attributed to strong absorbance in the near-infrared (NIR) region and high photothermal conversion efficiency. An earlier study witnessed a rapid increase in their development for cancer therapy, including CuS, Cu2-xSe and CuTe nanocrystals. However, a barrier is that the minimum laser power intensity for effective PTT is still significantly higher than the conservative limit for human skin exposure. Improving the photothermal conversion efficiency and reducing the laser power density has become a direction for the development of PTT. Furthermore, in an effort to improve the therapeutic efficacy, many multimode therapeutic nanostuctures have been formulated by integrating the photothermal agents with antitumor drugs, photosensitizers, or radiosensitizers, resulting in a synergistic effect. Various functional materials also have been absorbed, attached, encapsulated, or coated on the photothermal nanostructures, including fluorescence, computed tomography, magnetic resonance imaging, realizing cancer diagnosis, tumor location, site-specific therapy, and evaluation of therapeutic responses via incorporation of diagnosis and treatment. In this Account, we present an overview of the NIR-responsive photothermal semiconductor nanomaterials for cancer theranostics with a focus on their design and functionalization based on our own work. Our group has developed a series of chalcogenides with greatly improved NIR photoabsorption as photothermal agents, allowing laser exposure within regulatory limits. We also investigated the photothermal bioapplications of hypotoxic oxides including WO3-x, MoO3-x, and RuO2, expanding their applications into a new field of photothermal materials. Furthermore, considering a much more enhanced therapeutic effect of multifunctional nanoagents, our group elaborately designed many nanocomposites, such as core-shell nanoparticles of Fe3O4@Cu2-xS and Cu9S5@mSiO2, based on the integration of photothermal agents with contrast agents or other anticancer medicines, achieving cancer theranostic and synergistic treatment. Ternary compound nanocrystals were also prepared with synthetic simplicity for multimodal imaging-guided therapy for cancer. This Account summarizes our past work, including the design and concept, synthesis, and characterization for in vitro and in vivo applications. Then, we analyzed the tendencies of the NIR-responsive photothermal semiconductor nanomaterials for clinical applications, highlighting their prospects and challenges. We believe that the photothermal technology from the NIR-responsive photothermal semiconductor nanomaterials would promote cancer theranostics to result in giant strides forward in the future.

Surface Coating Constraint Induced Anisotropic Swelling of Silicon in Si-Void@SiO x Nanowire Anode for Lithium-Ion Batteries.

Here a simple and an environmentally friendly approach is developed for the fabrication of Si-void@SiOx nanowires of a high-capacity Li-ion anode material. The outer surface of the robust SiOx backbone and the inside void structure in Si-void@SiOx nanowires appropriately suppress the volume expansion and lead to anisotropic swelling morphologies of Si nanowires during lithiation/delithiation, which is first demonstrated by the in situ lithiation process. Remarkably, the Si-void@SiOx nanowire electrode exhibits excellent overall lithium-storage performance, including high specific capacity, high rate property, and excellent cycling stability. A reversible capacity of 1981 mAh g-1 is obtained in the fourth cycle, and the capacity is maintained at 2197 mAh g-1 after 200 cycles at a current density of 0.5 C. The outstanding overall properties of the Si-void@SiOx nanowire composite make it a promising anode material of lithium-ion batteries for the power-intensive energy storage applications.

Molten Au/Ge alloy migration in Ge nanowires.

Herein, we report time-resolved in situ transmission electron microscopy observation of Au particle melting at a Ge nanowire tip, subsequent forming of Au/Ge alloy liquid, and its migrating within the Ge nanowire. The migration direction and position of the Au/Ge liquid can be controlled by the applied voltage and the migration speed shows a linear deceleration in the nanowire. In a migration model proposed, the relevant dynamic mechanisms (electromigration, thermodiffusion, and viscous force, etc.) are discussed in detail. This work associated with the liquid mass transport in the solid nanowires should provide new insights into the crystal growth, interface engineering, and fabrication of the heterogeneous nanostructure-based devices.

Degradable Molybdenum Oxide Nanosheets with Rapid Clearance and Efficient Tumor Homing Capabilities as a Therapeutic Nanoplatform.

Molybdenum oxide (MoOx) nanosheets with high near-infrared (NIR) absorbance and pH-dependent oxidative degradation properties were synthesized, functionalized with polyethylene glycol (PEG), and then used as a degradable photothermal agent and drug carrier. The nanosheets, which are relatively stable under acidic pH, could be degraded at physiological pH. Therefore, MoOx-PEG distributed in organs upon intravenous injection would be rapidly degraded and excreted without apparent in vivo toxicity. MoOx-PEG shows efficient accumulation in tumors, the acidic pH of which then leads to longer tumor retention of those nanosheets. Along with the capability of acting as a photothermal agent for effective tumor ablation, MoOx-PEG can load therapeutic molecules with high efficiencies. This concept of inorganic theranostic nanoagent should be relatively stable in tumors to allow imaging and treatment, while being readily degradable in normal organs to enable rapid excretion and avoid long-term retention/toxicity.

Semiconductor heterojunction photocatalysts: design, construction, and photocatalytic performances.

Semiconductor-mediated photocatalysis has received tremendous attention as it holds great promise to address the worldwide energy and environmental issues. To overcome the serious drawbacks of fast charge recombination and the limited visible-light absorption of semiconductor photocatalysts, many strategies have been developed in the past few decades and the most widely used one is to develop photocatalytic heterojunctions. This review attempts to summarize the recent progress in the rational design and fabrication of heterojunction photocatalysts, such as the semiconductor-semiconductor heterojunction, the semiconductor-metal heterojunction, the semiconductor-carbon heterojunction and the multicomponent heterojunction. The photocatalytic properties of the four junction systems are also discussed in relation to the environmental and energy applications, such as degradation of pollutants, hydrogen generation and photocatalytic disinfection. This tutorial review ends with a summary and some perspectives on the challenges and new directions in this exciting and still emerging area of research.

High detectivity solar-blind high-temperature deep-ultraviolet photodetector based on multi-layered (l00) facet-oriented ß-Ga2O3 nanobelts.

Fabrication of a high-temperature deep-ultraviolet photodetector working in the solar-blind spectrum range (190-280 nm) is a challenge due to the degradation in the dark current and photoresponse properties. Herein, ß-Ga2O3 multi-layered nanobelts with (l00) facet-oriented were synthesized, and were demonstrated for the first time to possess excellent mechanical, electrical properties and stability at a high temperature inside a TEM studies. As-fabricated DUV solar-blind photodetectors using (l00) facet-oriented ß-Ga2O3 multi-layered nanobelts demonstrated enhanced photodetective performances, that is, high sensitivity, high signal-to-noise ratio, high spectral selectivity, high speed, and high stability, importantly, at a temperature as high as 433 K, which are comparable to other reported semiconducting nanomaterial photodetectors. In particular, the characteristics of the photoresponsivity of the ß-Ga2O3 nanobelt devices include a high photoexcited current (>21 nA), an ultralow dark current (below the detection limit of 10(-14) A), a fast time response (<0.3 s), a high R(λ) (≈851 A/W), and a high EQE (~4.2 × 10(3)). The present fabricated facet-oriented ß-Ga2O3 multi-layered nanobelt based devices will find practical applications in photodetectors or optical switches for high-temperature environment.

Glucose oxidase and ruthenium nanorods-embedded self-healing polyvinyl alcohol/polyethylene imine hydrogel for simultaneous photothermal/photodynamic/starvation therapy and skin reconstruction.

Tumor recurrence and wound healing represent significant burdens for tumor patients after the surgical removal of melanomas. Wound dressings with wound healing and anticancer therapeutic abilities could help to solve these issues. Thus, a hybrid hydrogel made of polyvinyl alcohol (PVA) and polyethylene imine (PEI) was prepared by cross-linking imine bond and boronic acid bond. This hydrogel was loaded with ruthenium nanorods (Ru NRs) and glucose oxidase (GOx) and named as nanocomposite hydrogel (Ru/GOx@Hydrogel), exhibiting remarkable photothermal/photodynamic/starvation antitumor therapy and wound repair abilities. Ru NRs are bifunctional phototherapeutic agents that simultaneously exhibit intrinsic photothermal and photodynamic functions. Three-dimensional composite hydrogel loaded with GOx can also consume glucose in the presence of O2 during tumor starvation therapy. Near-infrared (NIR) light-triggered hyperthermia can not only promote the consumption of glucose, but also facilitate the ablation of residual cancer cells. The antitumor effect of the Ru/GOx@Hydrogel resulted in significant improvements, compared to those observed with either phototherapy or starvation therapy alone. Additionally, the postoperative wound was substantially healed after treatment with Ru/GOx@Hydrogel and NIR irradiation. Therefore, the Ru/GOx@Hydrogel can be used as a multi-stimulus-responsive nanoplatform that could facilitate on-demand controlled drug release, and be used as a promising postoperative adjuvant in combination therapy.

Gallbladder microbial species and host bile acids biosynthesis linked to cholesterol gallstone comparing to pigment individuals.

Gallstones are crystalline deposits in the gallbladder that are traditionally classified as cholesterol, pigment, or mixed stones based on their composition. Microbiota and host metabolism variances among the different types of gallstones remain largely unclear. Here, the bile and gallstone microbial species spectra of 29 subjects with gallstone disease (GSD, 24 cholesterol and 5 pigment) were revealed by type IIB restriction site-associated DNA microbiome sequencing (2bRAD-M). Among them (21 subjects: 18 cholesterol and 3 pigment), plasma samples were subjected to liquid chromatography-mass spectrometry (LC-MS) untargeted metabolomics. The microbiome yielded 896 species comprising 882 bacteria, 13 fungi, and 1 archaeon. Microbial profiling revealed significant enrichment of Cutibacterium acnes and Microbacterium sp005774735 in gallstone and Agrobacterium pusense and Enterovirga sp013044135 in the bile of cholesterol GSD subjects. The metabolome revealed 2296 metabolites, in which malvidin 3-(6''-malonylglucoside), 2-Methylpropyl glucosinolate, and ergothioneine were markedly enriched in cholesterol GSD subjects. Metabolite set enrichment analysis (MSEA) demonstrated enriched bile acids biosynthesis in individuals with cholesterol GSD. Overall, the multi-omics analysis revealed that microbiota and host metabolism interaction perturbations differ depending on the disease type. Perturbed gallstone type-related microbiota may contribute to unbalanced bile acids metabolism in the gallbladder and host, representing a potential early diagnostic marker and therapeutic target for GSD.

A narrow-bandgap RuI3 nanoplatform to synergize radiotherapy, photothermal therapy, and thermoelectric dynamic therapy for tumor eradication.

Therapeutic resistance is an essential challenge for nanotherapeutics. Herein, a narrow bandgap RuI3 nanoplatform has been constructed firstly to synergize radiotherapy (RT), photothermal therapy (PTT), and thermoelectric dynamic therapy (TEDT) for tumor eradication. Specifically, the photothermal performance of RuI3 can ablate tumor cells while inducing TEDT. Noteworthy, the thermoelectric effect is found firstly in RuI3, which can spontaneously generate an electric field under the temperature gradient, prompting carrier separation and triggering massive ROS generation, thus aggravating oxidative stress level and effectively inhibiting HSP-90 expression. Moreover, RuI3 greatly enhances X-ray deposition owing to its high X-ray attenuation capacity, resulting in a pronounced computed tomography imaging contrast and DNA damage. In addition, RuI3 possesses both catalase-like and glutathione peroxidase-like properties, which alleviate tumor hypoxia and reduce antioxidant resistance, further exacerbating 1O2 production during RT and TEDT. This integrated therapy platform combining PTT, TEDT, and RT significantly inhibits tumor growth. STATEMENT OF SIGNIFICANCE: RuI3 nanoparticles were synthesized for the first time. RuI3 exhibited the highest photothermal properties among iodides, and the photothermal conversion efficiency was 53.38 %. RuI3 was found to have a thermoelectric effect, and the power factor could be comparable to that of most conventional thermoelectric materials. RuI3 possessed both catalase-like and glutathione peroxidase-like properties, which contributed to enhancing the effect of radiotherapy.

"Spark" PtMnIr Nanozymes for Electrodynamic-Boosted Multienzymatic Tumor Immunotherapy.

Multienzyme-mimicking redox nanozymes capable of efficient reactive oxygen species (ROS) generation and cellular homeostasis disruption are highly pursued for cancer therapy. However, it still faces challenges from the complicate tumor microenvironment (TME) and high chance for tumor metastasis. Herein, well-dispersed PtMnIr nanozymes are designed with multiple enzymatic activities, including catalase (CAT), oxidase (OXD), superoxide dismutase (SOD), peroxidase (POD), and glutathione peroxidase (GPx), which continuously produce ROS and deplete glutathione (GSH) concurrently in an "inner catalytic loop" way. With the help of electrodynamic stimulus, highly active "spark" species (Ir3+ and Mn3+) are significantly increased, resulting in an effective cascade enzymatic and electrodynamic therapy. Moreover, the cyclic generation of ROS can also facilitate ferroptosis and apoptosis in tumor cells, boosting synergistic therapy. Importantly, lung metastasis inhibition is found, which confirms efficient immunotherapy by the combined effect of immunogenic cell death (ICD) and Mn2+-induced cyclic guanosine monophosphate (GMP)-adenosine monophosphate (AMP) synthase (cGAS)-stimulator of interferon genes (cGAS-STING) pathway, contributing great potential in the treatment of malignant tumors.

Sub-10 nm Fe3O4@Cu(2-x)S core-shell nanoparticles for dual-modal imaging and photothermal therapy.

Photothermal nanomaterials have recently attracted significant research interest due to their potential applications in biological imaging and therapeutics. However, the development of small-sized photothermal nanomaterials with high thermal stability remains a formidable challenge. Here, we report the rational design and synthesis of ultrasmall (<10 nm) Fe3O4@Cu2-xS core-shell nanoparticles, which offer both high photothermal stability and superparamagnetic properties. Specifically, these core-shell nanoparticles have proven effective as probes for T2-weighted magnetic resonance imaging and infrared thermal imaging because of their strong absorption at the near-infrared region centered around 960 nm. Importantly, the photothermal effect of the nanoparticles can be precisely controlled by varying the Cu content in the core-shell structure. Furthermore, we demonstrate in vitro and in vivo photothermal ablation of cancer cells using these multifunctional nanoparticles. The results should provide improved understanding of synergistic effect resulting from the integration of magnetism with photothermal phenomenon, important for developing multimode nanoparticle probes for biomedical applications.