Hetero-Core-Shell BiNS-Fe@Fe as a Potential Theranostic Nanoplatform for Multimodal Imaging-Guided Simultaneous Photothermal-Photodynamic and Chemodynamic Treatment

Bioactive metal sulfide nanomaterials as photo-enhanced chemodynamic nanoreactors for tumor therapy

Metal sulfide nanomaterials (MeSNs) are highly promising for biomedical applications due to their low toxicity, good dispersibility, high stability, adjustable particle sizes, and good biocompatibility. Their unique chemical and light-conversion properties also enable them to function as photothermal or photodynamic agents, enhancing chemodynamic therapy (CDT) of tumors. This makes MeSNs valuable as photo-enhanced CDT nanoagents, advancing precision and multi-modal tumor treatment. This review examines recent advancements in MeSNs for photo-enhanced chemodynamic tumor ablation, comparing their effectiveness in CDT. It highlights the roles of photothermal, photodynamic, and photocatalytic effects in enhancing treatment efficacy. MeSN-based nanoreactors are categorized by composition into iron sulfide, copper sulfide, other unary, and multi-MeSNs for their applications in tumor therapy. Additionally, this review discusses challenges, limitations, and future biomedical applications of MeSNs, offering insights into their potential for next-generation cancer treatments.

Semiconductor-mediated radiosensitizers: progress, challenges and perspectives

Radiotherapy has become one indispensable treatment strategy for treating malignant tumors. However, the therapeutic effect of radiotherapy is limited due to the low sensitivity and large side effects of existing radiosensitizers. The rapid development of nanotechnology has created opportunities for various novel kinds of radiosensitizers with excellent radiosensitivity to sprout recently. In particular, due to the ease of modification and potential utilization capacity for a multifunctional radiotherapy platform, semiconductor radiosensitizers have attracted more and more attention. Recently, many novel semiconductor based radiosensitizers have been reported, which provides new ideas for the improvement of radiotherapy efficacy. To make further breakthroughs in semiconductor radiosensitizers, a systematic review is urgently needed and is herein provided. This review first elaborates on the principle of semiconductor induced radiosensitization, and then focuses on strategies such as doping and constructing heterojunctions to enhance the radiosensitivity of semiconductors. Next, it introduces in detail the principle and progress of different types of semiconductor radiosensitizers. Finally, challenges and perspectives of semiconductor radiosensitizers are proposed and discussed, offering guidance for future commercial applications of semiconductor radiosensitizers.

A Multifunctional MIL-101-NH2(Fe) Nanoplatform for Synergistic Melanoma Therapy

Background

Melanoma is an aggressive form of skin cancer, and single-modality treatments often fail to prevent tumor recurrence and metastasis. Combination therapy has emerged as an effective approach to improve treatment outcomes.

Methods

In this study, we developed a multifunctional nanoplatform, MIL@DOX@ICG, utilizing MIL-101-NH2(Fe) as a carrier to co-deliver the chemotherapeutic agent doxorubicin (DOX) and the photosensitizer indocyanine green (ICG). MIL-101-NH2(Fe) was synthesized via a hydrothermal method. Drug release was evaluated under different pH conditions, and the photothermal effect was tested under near-infrared (NIR) laser irradiation. Hydroxyl radical and reactive oxygen species generation capacities were quantified. Cellular studies using B16F10 cells assessed cytotoxicity, cellular uptake, migration inhibition, and colony formation suppression. In vivo experiments in melanoma-bearing mice evaluated antitumor efficacy and systemic safety through tumor growth inhibition, histological analyses, and toxicity assessments.

Results

MIL@DOX@ICG exhibited a uniform octahedral structure with a particle size of approximately 139 nm and high drug loading efficiencies for DOX (33.70%) and ICG (30.59%). The nanoplatform demonstrated pH-responsive drug release and potent photothermal effects. The generation of hydroxyl radicals via the Fenton reaction and reactive oxygen species production under NIR laser irradiation by MIL@DOX@ICG were confirmed. In vitro assessments revealed significant cytotoxicity of MIL@DOX@ICG against B16F10 cells under NIR laser irradiation, with improved efficacy in inhibiting cell proliferation and migration. In vivo studies confirmed the superior antitumor efficacy of MIL@DOX@ICG + NIR treatment, synergistically harnessing chemotherapy, photothermal therapy, photodynamic therapy, and chemodynamic therapy effects while maintaining excellent biocompatibility.

Conclusion

Our findings underscore the potential of MIL-101-NH2(Fe) nanoparticles as a versatile and effective platform for synergistic melanoma therapy, offering a promising strategy for overcoming the limitations of conventional treatment modalities.

Multi-Chambered Core/Shell Supraparticles for Real-Time, Full-Time Diagnosis and Treatment Integration of Tumors

To a certain extent, theranostic nanoplatforms promote tumor treatment efficiency. However, timely monitoring of the critical stages and signal sustainability of the entire process is challenging. In this study, multi-chambered core/shell magnetic nanoparticles (MC-MNPs) as drug and imaging agent multi-loaded nanocarriers with a synergistic release function are reported. Supraparticles with stable chambers are formed by the supercooling self-assembly of several core/shell magnetic nanoparticles composed of amphiphilic copolymers as the core and hydrophilic magnetic iron oxide nanoparticles as the shell. Desalinized doxorubicin and coumarin 6 are stored in different cavities of nanocarriers, and chitosan is used as an outer encapsulation layer. Based on their construction properties, MC-MNPs can exhibit gradient-degraded and steady-released controllability in the tumor environment. Furthermore, real-time accumulation situations and full-time diagnostic signals of nanocarriers are thoroughly demonstrated using fluorescence imaging and T2-weighted magnetic resonance imaging before and after magnetic hyperthermia in targeted tumors under an alternating magnetic field. Thus, MC-MNPs as theranostic nanocarriers exhibit great potential for the timely monitoring and full-time guidance of tumor treatment.

Bismuth-based photocatalysts for pollutant degradation and bacterial disinfection in sewage system: Classification, modification and mechanism

The discharge of polluted water poses a great threat to human health. Therefore, the development of effective sewage treatment technology is a key to achieve sustainable health development of society. Recent research showed that light-driven bismuth-based nanomaterials provided a promising chance for treating sewage system owing to their adjustable electronic features, excellent physical and chemical properties, abundant storage and environmental safety. However, the detailed overview and systematic understanding of the development of highly efficient bismuth-based photocatalysts is still unsatisfactory. In this review, we summarized the classification of bismuth-based photocatalysts, and the relationship between the structural design and the change of optical performance is illustrated. Importantly, the reliable modification strategies for improving photocatalytic capability are emphasized. Finally, the challenges and future development directions of light-driven bismuth-based nanoplatforms in wastewater treatment applications are discussed, hoping to provide an effective guidance for exploring the photocatalytic wastewater treatment process.

Heterojunction semiconductor nanocatalysts as cancer theranostics

Cancer nanotechnology is a promising area of cross-disciplinary research aiming to develop facile, effective, and noninvasive strategies to improve cancer diagnosis and treatment. Catalytic therapy based on exogenous stimulus-responsive semiconductor nanomaterials has shown its potential to address the challenges under the most global medical needs. Semiconductor nanocatalytic therapy is usually triggered by the catalytic action of hot electrons and holes during local redox reactions within the tumor, which represent the response of nontoxic semiconductor nanocatalysts to pertinent internal or external stimuli. However, careful architecture design of semiconductor nanocatalysts has been the major focus since the catalytic efficiency is often limited by facile hot electron/hole recombination. Addressing these challenges is vital for the progress of cancer catalytic therapy. In recent years, diverse strategies have been developed, with heterojunctions emerging as a prominent and extensively explored method. The efficiency of charge separation under exogenous stimulation can be heightened by manipulating the semiconducting performance of materials through heterojunction structures, thereby enhancing catalytic capabilities. This review summarizes the recent applications of exogenous stimulus-responsive semiconducting nanoheterojunctions for cancer theranostics. The first part of the review outlines the construction of different heterojunction types. The next section summarizes recent designs, properties, and catalytic mechanisms of various semiconductor heterojunctions in tumor therapy. The review concludes by discussing the challenges and providing insights into their prospects within this dynamic and continuously evolving field of research.

Advances in antitumor application of ROS enzyme-mimetic catalysts

The rapid growth of research on enzyme-mimetic catalysts (Enz-Cats) is expected to promote further advances in nanomedicine for biological detection, diagnosis and treatment of disease, especially tumors. ROS-based nanomedicines present fascinating potential in antitumor therapy owing to the rapid development of nanotechnology. In this review, we focus on the applications of Enz-Cats based on ROS in antitumor therapy. Firstly, the definition and category of ROS are introduced, and the key factors enhancing ROS levels are carefully elucidated. Then, the rationally engineered Enz-Cats via different synthetic approaches with high ROS-producing efficiencies are comprehensively discussed. Subsequently, oncotherapy application of Enz-Cats is comprehensively discussed, which integrates diverse synergistic treatment modalities and exhibits high efficiency in ROS generation. Finally, the challenges and future research direction of this field are presented. This review is dedicated to unraveling the enigmas surrounding the interplay of nanomedicine and organisms.

In situ autophagy regulation in synergy with phototherapy for breast cancer treatment

Autophagy is an important factor in reducing the efficacy of tumor phototherapy (including PTT and PDT). Accurate regulation of autophagy in tumor cells is a new strategy to improve the anti-tumor efficiency of PTT/PDT. This project intended to construct a tumor-activated autophagy regulator to efficiently block PTT/PDT-induced autophagy and realize synergistic sensitization to tumor phototherapy. To achieve this goal, we first synthesized TRANSFERRIN (Tf) biomimetic mineralized nano-tellurium (Tf-Te) as photosensitizer and then used disulfide bond reconstruction technology to induce Tf-Te self-assembly. The autophagy inhibitor hydroxychloroquine (HCQ) and iron ions carried by Tf were simultaneously loaded to prepare a tumor-responsive drug reservoir Tf-Te/HCQ. After entering breast cancer cells through the "self-guidance system", Tf-Te/HCQ can generate hyperpyrexia and ROS under NIR laser irradiation, to efficiently induce PTT/PDT effect. Meanwhile, the disulfide bond broke down in response to GSH, and the nanoparticles disintegrated to release Fe2+ and HCQ at fixed points. They simultaneously induce lysosomal alkalinization and increased osmotic pressure, effectively inhibit autophagy, and synergistically enhance the therapeutic effect of phototherapy. In vivo anti-tumor results have proved that the tumor inhibition rate of Tf-Te/HCQ can be as high as 88.6% on 4T1 tumor-bearing mice. This multifunctional drug delivery system might provide a new alternative for more precise and effective tumor phototherapy.

Reactive oxygen species-upregulating nanomedicines towards enhanced cancer therapy

Reactive oxygen species (ROS) play a crucial role in physiological and pathological processes, emerging as a therapeutic target in cancer. Owing to the high concentration of ROS in solid tumor tissues, ROS-based treatments, such as photodynamic therapy and chemodynamic therapy, and ROS-responsive drug delivery systems have been widely explored to powerfully and specifically suppress tumors. However, their anticancer efficacy is still hampered by the heterogeneous ROS levels, and thus comprehensively upregulating the ROS levels in tumor tissues can ensure an enhanced therapeutic effect, which can further sensitize and/or synergize with other therapies to inhibit tumor growth and metastasis. Herein, we review the recently emerging drug delivery strategies and technologies for increasing the H₂O₂, ˙OH, ¹O₂, and ˙O₂^- concentrations in cancer cells, including the efficient delivery of natural enzymes, nanozymes, small molecular biological molecules, and nanoscale Fenton-reagents and semiconductors and neutralization of intracellular antioxidant substances and localized input of mechanical and electromagnetic waves (such as ultrasound, near infrared light, microwaves, and X-rays). The applications of these ROS-upregulating nanosystems in enhancing and synergizing cancer therapies including chemotherapy, chemodynamic therapy, phototherapy, and immunotherapy are surveyed. In addition, we discuss the challenges of ROS-upregulating systems and the prospects for future studies.

Efficient improvement in chemo/photothermal synergistic therapy against lung cancer using Bi@Au nano-acanthospheres

Novel highly hydrophilic and biocompatible bismuth nanospheres with gold nanoparticles growing outside (Bi@Au nano-acanthospheres, Bi@Au NASs) were synthesized through a simple procedure, which demonstrated to be a promising photothermal agent owing to the ultrahigh photothermal conversion efficiency (η = 46.6 %). The as-prepared Bi@Au NASs showed excellent blood compatibility and fairly low cytotoxicity to human lung cancer A549 cells, as well as efficient photothermal ablation (PTA) therapy induced by a near-infrared laser. Under the 808 nm laser radiation, the tumour temperature could be elevated by ∼25 °C high enough to kill the cancer cells. Moreover, the anticancer drug doxorubicin hydrochloride (DOX) was successfully loaded in Bi@Au NASs with a loading content as high as 16.78 % and released under a pH sensitive release profile, a characteristic beneficial for intravenous delivery of DOX into cancer cells for chemotherapy. The presence of the Bi element enabled Bi@Au NASs to act as a favourable computed tomography (CT) contrast medium for CT imaging-guided tumour treatment. Compared with cancer treatment through either photothermal therapy or chemotherapy, the chemo-photothermal synergistic therapy using Bi@Au NASs as both a photothermal agent and a drug carrier has efficiently enhanced the in vitro and in vivo therapeutic effects in cancer treatment.

Multistage O2-producing liposome for MRI-guided synergistic chemodynamic/chemotherapy to reverse cancer multidrug resistance

Reduced drug uptake and elevated drug efflux are two major mechanisms in cancer multidrug resistance (MDR). In the present study, a new multistage O₂-producing liposome with NAG/R8-dual-ligand and stimuli-responsive dePEGylation was developed to address the abovementioned issues simultaneously. The designed C-NAG-R8-PTXL/MnO₂-lip could also achieve magnetic resonance imaging (MRI)-guided synergistic chemodynamic/chemotherapy (CDT/CT). In vitro and in vivo studies showed that C-NAG-R8-PTXL/MnO₂-lip enhanced circulation time by PEG and targeted the tumor site. After tumor accumulation, endogenous l-cysteine was administered, and the PEG-attached disulfide bond was broken, resulting in the dissociation of PEG shells. The previously hidden positively charged R8 by different lengths of PEG chains was exposed and mediated efficient internalization. In addition, the oxygen (O₂) generated by C-NAG-R8-PTXL/MnO₂-lip relieved the hypoxic environment within the tumor, thus reducing the efflux of chemotherapeutic drug. O₂ was able to burst liposomes and triggered the release of PTXL. The toxic hydroxyl radical (·OH), which was produced by H₂O₂ and Mn²⁺, strengthened CDT/CT. C-NAG-R8-PTXL/MnO₂-lip was also used as MRI contrast agent, which blazed the trail to rationally design theranostic agents for tumor imaging.

"Cluster Bomb" Based Bismuth Nano-in-Micro Spheres Formed Dry Powder Inhalation for Thermo-Radio Sensitization Effects of Lung Metastatic Breast Cancer

Lung metastatic breast cancer (LMBC) is mainly diagnosed through CT imaging and radiotherapy could be the most common method in the clinic to inhibit tumor proliferation. While the sensitivity of radiotherapy is always limited due to the hypoxic tumor microenvironment and high doses of irradiation easily induce systemic cytotoxicity. Metal-based materials applied as radiosensitizers have been widely investigated to improve efficiency and reduce the doses of irradiation. Herein, it is aimed to overcome these problems by designing biodegradable lipid-camouflaged bismuth-based nanoflowers (DP-BNFs) as both a photo-thermo-radiosensitizer to develop a novel photothermal therapy (PTT) and radiotherapy combination strategy for LMBC treatment. To achieve effective lung deposition, "Cluster Bomb" structure-based DP-BNFs nano-in-micro dry powder inhalation (DP-BNF@Lat-MPs) are formulated through spray-dried technology. The DP-BNFs "cluster" in the microsphere to improve their tumor-targeted lung deposition with a high fine particle fraction followed by burst releasing of DP-BNFs for targeting delivery and LMBC therapy. The DP-BNF@Lat-MPs exhibit excellent photothermal conversion efficiency, radiotherapy enhancement, and CT imaging ability in vitro, which synergistically inhibit cell proliferation and metastasis. In vitro and in vivo data prove that combining PTT and radiotherapy with DP-BNF@Lat-MPs as a thermo-radio dual-sensitizer significantly enhances LMBC tumor metastasis inhibition with good biocompatibility and low toxicity.

Smart nanocomposite assemblies for multimodal cancer theranostics

Despite great strides in anticancer research, performance statistics of current treatment modalities remain dismal, highlighting the need for safe, efficacious strategies for tumour mitigation. Non-invasive fusion technology platforms combining photodynamic, photothermal and hyperthermia therapies have emerged as alternate strategies with potential to meet many of the unmet clinical demands in the domain of cancer. These therapies make use of metallic and magnetic nanoparticles with light absorbing properties, which are manipulated to generate either reactive cytotoxic oxygen species or heat for tumour ablation. Combination therapies integrating light, heat and magnetism-mediated nanoplatforms with the conventional approaches of chemotherapy, radiotherapy and surgery are emerging as precision medicine for targeted interventions against cancer. This article aims to compile recent developments of advanced nanocomposite assemblies that integrate multimodal therapeutics for cancer treatment. Amalgamation of various effective, non-invasive technological platforms such as photodynamic therapy (PDT), photothermal therapy (PTT), magnetic hyperthermia (MHT), and chemodynamic therapy (CDT) have tremendous potential in presenting safe and efficacious solutions to the formidable challenges in cancer therapeutics.

Chemodynamic Therapy via Fenton and Fenton-Like Nanomaterials: Strategies and Recent Advances

Chemodynamic therapy (CDT), a novel cancer therapeutic strategy defined as the treatment using Fenton or Fenton-like reaction to produce •OH in the tumor region, was first proposed by Bu, Shi, and co-workers in 2016. Recently, with the rapid development of Fenton and Fenton-like nanomaterials, CDT has attracted tremendous attention because of its unique advantages: 1) It is tumor-selective with low side effects; 2) the CDT process does not depend on external field stimulation; 3) it can modulate the hypoxic and immunosuppressive tumor microenvironment; 4) the treatment cost of CDT is low. In addition to the Fe-involved CDT strategies, the Fenton-like reaction-mediated CDT strategies have also been proposed, which are based on many other metal elements including copper, manganese, cobalt, titanium, vanadium, palladium, silver, molybdenum, ruthenium, tungsten, cerium, and zinc. Moreover, CDT has been combined with other therapies like chemotherapy, radiotherapy, phototherapy, sonodynamic therapy, and immunotherapy for achieving enhanced anticancer effects. Besides, there have also been studies that extend the application of CDT to the antibacterial field. This review introduces the latest advancements in the nanomaterials-involved CDT from 2018 to the present and proposes the current limitations as well as future research directions in the related field.

Sprayable β-FeSi2 composite hydrogel for portable skin tumor treatment and wound healing

The development of a rapid-forming in-situ sprayable hydrogel with the functions of tumor treatment and wound healing is essential for eliminating residual tumor tissue and promoting wound healing caused by surgical resection. On account of its semiconductor properties, β-FeSi₂ (FS) was widely explored as a thermoelectric material. In this work, FS was first applied as a bioactive material for the application of tissue engineering. Excitedly, we found that FS could be used as a novel antitumor agent. It exhibited excellent photothermal performance, and the released Fe ions could generate •OH under the acidic conditions and excessive H₂O₂ in the tumor microenvironment. Moreover, the sprayable β-FeSi₂-incorporated sodium alginate (FS/SA) hydrogel was prepared as an instant gelation after spraying in situ, contributing to timely tumor-induced skin wound healing and efficiently suppressing tumors through photothermal and chemodynamic therapy (PTT and CDT). Furthermore, the released bioactive Fe and Si ions could promote the migration and differentiation of endothelial cells and the pro-angiogenesis of skin wounds. Accordingly, such sprayable hydrogel played an effective role in emergency wound treatment with the advantage of convenience and portability. Overall, with incorporation of FS into the sprayable FS/SA hydrogel, the composite hydrogel possessed dual functions of tumor therapy and skin wound healing.

Ultrathin 2D Inorganic Ancient Pigment Decorated 3D-Printing Scaffold Enables Photonic Hyperthermia of Osteosarcoma in NIR-II Biowindow and Concurrently Augments Bone Regeneration

Osteosarcoma (OS) is the primary malignant bone tumor. Despite therapeutic strategies including surgery, chemotherapy, and radiotherapy have been introduced into the war of fighting OS, the 5-year survival rate for patients still remains unchangeable for decades. Besides, the critical bone defects after surgery, drug-resistance and side effects also attenuate the therapeutic effects and predict poor prognosis. Recently, photothermal therapy (PTT) has attracted extensive attention featuring minimal invasiveness and high spatial-temporal precision characteristics. Herein, an ultrathin 2D inorganic ancient pigment Egyptian blue decorated 3D-printing scaffold (CaPCu) with profound PTT efficacy at the second near-infrared (NIR-II) biowindow against OS and enhanced osteogenesis performance is successfully constructed. Importantly, this work uncovers the underlying biological mechanisms that genes associated with cell death, proliferation, and bone development are regulated by CaPCu-scaffold-based therapy. This work not only elucidates the fascinating clinical translation prospects of CaPCu-scaffold-based PTT against OS in NIR-II biowindow, but also demonstrates the potential mechanisms and offers a novel strategy to develop the next-generation, multifunctional tissue-engineering biomaterials.