Ultrathin Transition Metal Chalcogenide Nanosheets Synthesized via Topotactic Transformation for Effective Cancer Theranostics

A LDH-Derived Metal Sulfide Nanosheet-Functionalized Bioactive Glass Scaffold for Vascularized Osteogenesis and Periprosthetic Infection Prevention/Treatment

Periprosthetic infection and prosthetic loosing stand out as prevalent yet formidable complications following orthopedic implant surgeries. Synchronously addressing the two complications is long-time challenging. Herein, a bioactive glass scaffold (BGS) functionalized with MgCuFe-layered double hydroxide (LDH)-derived sulfide nanosheets (BGS/MCFS) is developed for vascularized osteogenesis and periprosthetic infection prevention/treatment. Apart from the antibacterial cations inhibiting bacterial energy and material metabolism, the exceptional near-infrared-II (NIR-II) photothermal performance empowers BGS/MCFS to eliminate periprosthetic infections, outperforming previously reported functionalized BGS. The rough surface topography and the presence of multi-bioactive metal ions bestow BGS/MCFS with exceptional osteogenic and angiogenic properties, with 8.5-fold and 2.3-fold enhancement in bone mass and neovascularization compared with BGS. Transcriptome sequencing highlights the involvement of the TGF-β signaling pathway in these processes, while single-cell sequencing reveals a significant increase in osteoblasts and endothelial cells around BGS/MCFS compared to BGS.

Improvement photothermal property of MoS2/Fe3O4/GNR nanocomposite in cancer treatment

The objective of the present study was to develop a novel molybdenum disulfide/iron oxide/gold nanorods (MoS2/Fe3O4/GNR) nanocomposite (MFG) with different concentrations of AgNO3 solution (MFG1, MFG2, and MFG3) for topical doxorubicin (DOX) drug delivery. Then, these nanocomposites were synthesized and characterized by Fourier transform infrared (FTIR), Transmission electron microscopy (TEM), Dynamic light scattering (DLS), and Ultraviolet-visible (UV-Vis) spectroscopies to confirm their structural and optical properties. Cytotoxicity of samples on Hela cell was determined using MTT assay. Results indicated that nanocomposites possess little cytotoxicity without NIR laser irradiation. Also, the relative viabilities of Hela cells decreased when the concentration of AgNO3 solution increased in this nanocomposite. Using NIR irradiation, the relative viabilities of Hela cells decreased when the concentration of samples increased. Acridine orange/propidium iodide (PI) staining, flow cytometry were recruited to evaluate the effect of these nanocomposites on apoptosis of Hela cells. Finally, results revealed when DOX loading increased in nanocomposite, then cell viability was decreased in it. Therefore, these properties make MFG3 nanocomposite a good candidate for photothermal therapy and drug loading.

Ultrasound-Based Micro-/Nanosystems for Biomedical Applications

Due to the intrinsic non-invasive nature, cost-effectiveness, high safety, and real-time capabilities, besides diagnostic imaging, ultrasound as a typical mechanical wave has been extensively developed as a physical tool for versatile biomedical applications. Especially, the prosperity of nanotechnology and nanomedicine invigorates the landscape of ultrasound-based medicine. The unprecedented surge in research enthusiasm and dedicated efforts have led to a mass of multifunctional micro-/nanosystems being applied in ultrasound biomedicine, facilitating precise diagnosis, effective treatment, and personalized theranostics. The effective deployment of versatile ultrasound-based micro-/nanosystems in biomedical applications is rooted in a profound understanding of the relationship among composition, structure, property, bioactivity, application, and performance. In this comprehensive review, we elaborate on the general principles regarding the design, synthesis, functionalization, and optimization of ultrasound-based micro-/nanosystems for abundant biomedical applications. In particular, recent advancements in ultrasound-based micro-/nanosystems for diagnostic imaging are meticulously summarized. Furthermore, we systematically elucidate state-of-the-art studies concerning recent progress in ultrasound-based micro-/nanosystems for therapeutic applications targeting various pathological abnormalities including cancer, bacterial infection, brain diseases, cardiovascular diseases, and metabolic diseases. Finally, we conclude and provide an outlook on this research field with an in-depth discussion of the challenges faced and future developments for further extensive clinical translation and application.

Ternary NiCoTi-layered double hydroxide nanosheets as a pH-responsive nanoagent for photodynamic/chemodynamic synergistic therapy

Combining photodynamic therapy (PDT) with chemodynamic therapy (CDT) has been proven to be a promising strategy to improve the treatment efficiency of cancer, because of the synergistic therapeutic effect arising between the two modalities. Herein, we report an inorganic nanoagent based on ternary NiCoTi-layered double hydroxide (NiCoTi-LDH) nanosheets to realize highly efficient photodynamic/chemodynamic synergistic therapy. The NiCoTi-LDH nanosheets exhibit oxygen vacancy-promoted electron-hole separation and photogenerated hole-induced O2-independent reactive oxygen species (ROS) generation under acidic circumstances, realizing in situ pH-responsive PDT. Moreover, due to the effective conversion between Co3+ and Co2+ caused by photogenerated electrons, the NiCoTi-LDH nanosheets catalyze the release of hydroxyl radicals (·OH) from H2O2 through Fenton reactions, resulting in CDT. Laser irradiation enhances the catalyzed ability of the NiCoTi-LDH nanosheets to promote the ROS generation, resulting in a better performance than TiO2 nanoparticles at pH 6.5. In vitro and in vivo experimental results show conclusively that NiCoTi-LDH nanosheets plus irradiation lead to efficient cell apoptosis and significant inhibition of tumor growth. This study reports a new pH-responsive inorganic nanoagent with oxygen vacancy-promoted photodynamic/chemodynamic synergistic performance, offering a potentially appealing clinical strategy for selective tumor elimination.

Simple synthesis of peanut shell-like MoCoFe-HO@CoMo-LDH for efficient alkaline oxygen evolution reaction

Due to the depletion of fossil energy on earth, it is crucial to develop resource rich and efficient non-precious metal electrocatalysts for oxygen evolution reaction (OER). Herein, we synthesized an efficient and economical electrocatalyst using a simple self-assembly strategy. Firstly, rod-shaped MIL-88A was synthesized by hydrothermal method. Then, the surface of MIL-88A was functionalized and encapsulated in zeolitic imidazolate framework-67 (ZIF-67) by hydrothermal method. The combination of MIL-88A and ZIF-67 resulted in a slight ion-exchange reaction between Co2+ and the surface of MIL-88A to generate CoFe-LDH@ZIF-67 core-shell structure. Afterwards, in the presence of Mo6+, ZIF-67 was converted into CoMo-nanocages through ion-exchange reactions, forming a core-shell structure of MoCoFe hydr (oxy) oxide@CoMo-LDH (MoCoFe-HO@CoMo-LDH). Due to the advantages of core-shell structure and composition, this material exhibits excellent OER characteristics, with a small Tafel slope (45.11 mV dec-1) and low overpotential (324 mV) at 10 mA cm-2. It exhibits good stability in alkaline media. This research work provides a novel approach for the development of efficient and economical non-precious metal electrocatalysts.

Coupling Probiotics with 2D CoCuMo-LDH Nanosheets as a Tumor-Microenvironment-Responsive Platform for Precise NIR-II Photodynamic Therapy

Photodynamic therapy (PDT) has become a promising cancer treatment approach with superior advantages. However, it remains a grand challenge to develop tumor microenvironment (TME)-responsive photosensitizers (PSs) for tumor-targeting precise PDT. Herein, the coupling Lactobacillus acidophilus (LA) probiotics with 2D CoCuMo layered-double-hydroxide (LDH) nanosheets (LA&LDH) is reported as a TME-responsive platform for precise NIR-II PDT. The CoCuMo-LDH nanosheets loaded on LA can be transformed from crystalline into amorphous through etching by the LA-metabolite-enabled low pH and overexpressed glutathione. The TME-induced in situ amorphization of CoCuMo-LDH nanosheets can boost its photodynamic activity for singlet oxygen (¹ O₂ ) generation under 1270 nm laser irradiation with relative ¹ O₂ quantum yield of 1.06, which is the highest among previously reported NIR-excited PSs. In vitro and in vivo assays prove that the LA&LDH can effectively achieve complete cell apoptosis and tumor eradication under 1270 nm laser irradiation. This study proves that the probiotics can be used as a tumor-targeting platform for highly efficient precise NIR-II PDT.

Targeted alleviation of ischemic stroke reperfusion via atorvastatin-ferritin Gd-layered double hydroxide

In acute ischemic stroke therapy, potent neuroprotective agents are needed that prevent neural injuries caused by reactive oxygen species (ROS) during ischemic reperfusion. Herein, a novel 2D neuroprotective agent (AFGd-LDH) is reported, comprising Gd-containing layered double hydroxide nanosheets (Gd-LDH, as a drug nanocarrier/MRI contrast agent), atorvastatin (ATO, as a neuroprotective drug) and the ferritin heavy subunit (FTH, as a blood brain barrier transport agent). Experiments revealed AFGd-LDH to possess outstanding antioxidant activity, neuroprotective properties, blood‒brain barrier transit properties, and biocompatibility. In vitro studies demonstrated the ROS scavenging efficiency of AFGd‒LDH to be ∼90%, surpassing CeO₂ (50%, a ROS scavenger) and edaravone (52%, a clinical neuroprotective drug). Ischemia‒reperfusion model studies in mice showed AFGd‒LDH could dramatically decrease apoptosis induced by reperfusion, reducing the infarct area by 67% and lowering the neurological deficit score from 3.2 to 0.9. AFGd-LDH also offered outstanding MRI performance, thus enabling simultaneous imaging and ischemia reperfusion therapy.

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The simple stepwise method was used to construct AFGd-LDH by the confinement of atorvastatin and the ferritin heavy subunit (FTH) with Gd-LDH.

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AFGd-LDH demonstrated outstanding antioxidant activity and ROS scavenging efficiency.

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AFGd-LDH offered neuroprotective properties to dramatically decrease apoptosis induced by reperfusion.

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AFGd-LDH presented blood‒brain barrier transit properties and outstanding MRI performance, thus enabling simultaneous imaging and ischemia reperfusion therapy.

Synthesis of dual-stimuli responsive metal organic framework-coated iridium oxide nanocomposite functionalized with tumor targeting albumin-folate for synergistic photodynamic/photothermal cancer therapy

The synergistic effects of photothermal therapy (PTT) and photodynamic therapy (PDT) has attracted considerable attention in the field of cancer therapy because of its excellent anti-tumor effect. This work provides a novel pH/NIR responsive therapeutic nanoplatform, IrO₂@ZIF-8/BSA-FA (Ce6), producing a synergistic effect of PTT-PDT in the treatment of osteosarcoma. Iridium dioxide nanoparticles (IrO₂ NPs) with exceptional catalase-like activity and PTT effects were synthesized by a hydrolysis method and decorated with zeolitic imidazolate framework-8 (ZIF-8) shell layer to promote the physical absorption of Chlorin e6 (Ce6), and further functionalized with bovine serum albumin-folate acid (BSA-FA) for targeting tumor cells. The IrO₂@ZIF-8/BSA-FA nanocomposite indicated an outstanding photothermal heating conversion efficiency of 62.1% upon laser irradiation. In addition, the Ce6 loading endows nanoplatform with the capability to induce cell apoptosis under 660 nm near-infrared (NIR) laser irradiation through a reactive oxygen species (ROS)-mediated mechanism. It was further testified that IrO₂@ZIF-8/BSA-FA can function as a catalase and convert the endogenous hydrogen peroxide (H₂O₂) into oxygen (O₂) to improve the local oxygen pressure under the acidic tumor microenvironment (TME), which could subsequently amplified PDT-mediated ROS cell-killing performance via relieving hypoxia microenvironment of tumor. Both in vitro and in vivo experimental results indicated that the nanomaterials were good biocompatibility, and could remarkably achieve tumor-specific and enhanced combination therapy outcomes as compared with the corresponding PTT or PDT monotherapy. Taken together, this work holds great potential to design an intelligent multifunctional therapeutic nanoplatform for cancer therapy.

A Multifunctional Cascade Bioreactor Based on a Layered Double Oxides Composite Hydrogel for Synergetic Tumor Chemodynamic/Starvation/Photothermal Therapy

The field of nanomedicine-catalyzed tumor therapy has achieved a lot of progress; however, overcoming the limitations of the tumor microenvironment (TME) to achieve the desired therapeutic effect remains a major challenge. In this study, a nanocomposite hydrogel (GH@LDO) platform combining the nanozyme CoMnFe-layered double oxides (CoMnFe-LDO) and natural enzyme glucose oxidase (GOX) was engineered to remodel the TME to enhance tumor catalytic therapy. The CoMnFe-LDO is a nanozyme that can convert endogenous H₂O₂ into reactive oxygen species (ROS) and O₂ to achieve chemodynamic therapy (CDT) and alleviate the hypoxic microenvironment. Meanwhile, GOX can catalyze the conversion of glucose and O₂ to gluconic acid and H₂O₂, which not only represses the ATP production of tumor cells to achieve starvation therapy (ST), but also decreases the pH value of TME and supplies extra H₂O₂ to enhance the CDT effect. Furthermore, this well-designed CoMnFe-LDO possessed a high photothermal conversion efficiency (66.63%), which could promote the generation of ROS to enhance the CDT effect and achieve photothermal therapy (PTT) under near-infrared light irradiation. The GH@LDO hydrogel cascade reaction overcomes the limitation of the TME and achieves satisfactory CDT/ST/PTT synergetic effects in vitro and in vivo. This work provides a new strategy for remodeling the TME using nanomedicine to achieve precise tumor cascaded catalytic therapy. STATEMENT OF SIGNIFICANCE: At present, the focus of tumor therapy has begun to shift from monotherapy to combination therapy for improving the overall therapeutic effect. In this study, we synthesized a CoMnFe-layered double oxide (CoMnFe-LDO) nanozyme composed of multiple transition metal oxides, which demonstrated improved peroxidase and oxidase activities as well as favorable photothermal conversion capability. The CoMnFe-LDO nanozyme was compounded with an injectable GH hydrogel crosslinked by glucose oxidase (GOX) and peroxidase (HRP). This nanocomposite hydrogel overcame the limitations of weak acidity, H₂O₂, and O₂ levels in the tumor microenvironment (TME) and achieved synergetic chemodynamic therapy (CDT), starvation therapy (ST), and photothermal therapy (PTT) effects based on the cascaded catalytic actions of CoMnFe-LDO and GOX to H₂O₂ and glucose.

Progress of Nanomaterials-Based Photothermal Therapy for Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) is one of the top 15 most prevalent cancers worldwide. However, the current treatment models for OSCC (e.g., surgery, chemotherapy, radiotherapy, and combination therapy) present several limitations: damage to adjacent healthy tissue, possible recurrence, low efficiency, and severe side effects. In this context, nanomaterial-based photothermal therapy (PTT) has attracted extensive research attention. This paper reviews the latest progress in the application of biological nanomaterials for PTT in OSCC. We divide photothermal nanomaterials into four categories (noble metal nanomaterials, carbon-based nanomaterials, metal compounds, and organic nanomaterials) and introduce each category in detail. We also mention in detail the drug delivery systems for PTT of OSCC and briefly summarize the applications of hydrogels, liposomes, and micelles. Finally, we note the challenges faced by the clinical application of PTT nanomaterials and the possibility of further improvement, providing direction for the future research of PTT in OSCC treatment.

Layered double hydroxide-based nanomaterials for biomedical applications

Against the backdrop of increased public health awareness, inorganic nanomaterials have been widely explored as promising nanoagents for various kinds of biomedical applications. Layered double hydroxides (LDHs), with versatile physicochemical advantages including excellent biocompatibility, pH-sensitive biodegradability, highly tunable chemical composition and structure, and ease of composite formation with other materials, have shown great promise in biomedical applications. In this review, we comprehensively summarize the recent advances in LDH-based nanomaterials for biomedical applications. Firstly, the material categories and advantages of LDH-based nanomaterials are discussed. The preparation and surface modification of LDH-based nanomaterials, including pristine LDHs, LDH-based nanocomposites and LDH-derived nanomaterials, are then described. Thereafter, we systematically describe the great potential of LDHs in biomedical applications including drug/gene delivery, bioimaging diagnosis, cancer therapy, biosensing, tissue engineering, and anti-bacteria. Finally, on the basis of the current state of the art, we conclude with insights on the remaining challenges and future prospects in this rapidly emerging field.

Defect engineering of layered double hydroxide nanosheets as inorganic photosensitizers for NIR-III photodynamic cancer therapy

Although two-dimensional (2D) layered double hydroxides (LDHs) have been widely used as efficient nanoagents for biological diagnosis and treatment, they have been found to be inert as photosensitizers (PSs) for photodynamic therapy (PDT). Herein, we report the defect engineering of ultrathin 2D CoMo-LDH and NiMo-LDH nanosheets as highly active inorganic PSs for PDT in the third near-infrared (NIR-III) window. Hydrothermal-synthesized 2D CoMo-LDH and NiMo-LDH nanosheets are etched via a simple acid treatment to obtain defect-rich CoMo-LDH and NiMo-LDH nanosheets. Importantly, the defect-rich CoMo-LDH nanosheets exhibit much higher activity (~97 times) for generation of reactive oxygen species than that of the pristine CoMo-LDH nanosheets under a NIR-III 1567 nm laser irradiation. Therefore, after modification with polyethylene glycol, the defect-rich CoMo-LDH nanosheets can be used as an efficient inorganic PS for PDT to efficiently induce cancer cells apoptosis in vitro and eradicate tumors in vivo under 1567 nm laser irradiation.

Defect engineering of 2 dimensional layered double hydroxide sheets improves their photocatalytic activity. Here, the authors etch sheets in acid and show that the etched sheets generate substantially more reactive oxygen species that untreated sheets and the treated sheets can be used to kill cancer cells in vitro and in vivo.

Carrier-Free Delivery of Ultrasmall π-Conjugated Oligomer Nanoparticles with Photothermal Conversion over 80% for Cancer Theranostics

High-performance photothermal theranostics is urgently desired for cancer therapy because of their good controllability and noninvasive features. The relatively low photothermal conversion efficiency is still at the drawbacks because of the absence of efficient extraneous carriers. Herein, a carrier-free nanomedicine is developed to in vivo self-deliver organic photothermal agents for efficient cancer phototheranostics. By a facile self-assembly strategy, the near-infrared (NIR)-absorbing conjugated oligomer IDIC-4F is fabricated into a carrier-free nanoparticle (DCF-P), showing ultrasmall size of nearly 4.0 nm with a nearly 100% of drug loading capacity. Notably, DCF-P achieves a superhigh photothermal conversion efficiency of 80.5% that is far greater than that of IDIC-4F-loaded nanomicelle DCF-M (57.3%). With the guidance of NIR fluorescence and photoacoustic dual-imaging, it is verified that DCF-P could well achieve tumor-preferential accumulation and retention at 4 h postinjection, and meanwhile shows highly efficient in vivo tumor elimination with good biosafety. This study thus contributes a novel concept for designing ultrasmall nanoparticle characteristics of preferential accumulation in tumors, and also provides a strategy for creating high-performance carrier-free nanomedicine via highly ordered molecular stacking.

Transdermal Photothermal Sterilization and Abscess Elimination Research of BSA-CuS Nanoparticles in vivo

The treatment of subcutaneous abscess caused by drug-resistant bacteria is facing great difficulties and receiving more attention. In this work, we employed BSA-CuS nanoparticles as a photothermal reagent to apply photothermal therapy (PTT) to combat drug-resistant bacteria in vitro and subcutaneous abscess in vivo. The BSA-CuS nanoparticles were found to be stable and biocompatible without cytotoxicity toward NIH3T3 and 4T1 cells. In vitro experiments showed that three species of drug-resistant pathogens, including Escherichia coli, Staphylococcus aureus, and Candida albicans, could be effectively sterilized under co-incubation with BSA-CuS nanoparticles and then irradiation with 1064 nm NIR laser via tissue penetration. BSA-CuS nanoparticles together with 1064 nm NIR laser irradiation could also effectively diminish subcutaneous abscesses caused by drug-resistant bacteria on mice under PTT and depth PTT without causing any serious side effects and organic damage in vivo.That is OK, thank you!

Recent advances in near infrared light responsive multi-functional nanostructures for phototheranostic applications

Light-based theranostics have become indispensable tools in the field of cancer nanomedicine. Specifically, near infrared (NIR) light mediated imaging and therapy of deeply seated tumors using a single multi-functional nanoplatform have gained significant attention. To this end, several multi-functional nanomaterials have been utilized to tackle cancer and thereby achieve significant outcomes. The present review mainly focuses on the recent advances in the development of NIR light activatable multi-functional materials such as small molecules, quantum dots, and metallic nanostructures for the diagnosis and treatment of deeply seated tumors. The need for improved disease detection and enhanced treatment options, together with realistic considerations for clinically translatable nanomaterials will be the key driving factors for theranostic agent research in the near future. NIR-light mediated cancer imaging and therapeutic approaches offer several advantages in terms of minimal invasiveness, deeper tissue penetration, spatiotemporal resolution, and molecular specificities. Herein, we have reviewed the recent developments in NIR light responsive multi-functional nanostructures for phototheranostic applications in cancer therapy.

Near-infrared inorganic nanomaterial-based nanosystems for photothermal therapy

The development of robust materials for treating diseases through non-invasive photothermal therapy (PTT) has attracted increasing attention in recent years. Among various types of nanomaterials, inorganic nanomaterials with strong absorption in the near-infrared (NIR) window can be employed as high-efficiency photothermal agents to treat cancer and bacterial infections. In addition, inorganic nanomaterials can be easily combined with other drugs or chemical reagents to construct multifunctional nanomaterials to cascade stimulation responses, enhance therapeutic effects, and perform precise medical treatments. In this review, focusing on the latest developments of inorganic nanomaterials in photothermal therapy, we firstly introduced the light-to-heat conversion mechanism of inorganic nanomaterials. Secondly, we summarized the application of common inorganic nanomaterials, such as metallic nanoparticles, transition metal oxide nanoparticles and two dimensional (2D) nanosheets. In addition, the strategy of developing multifunctional nano-platforms with excellent biocompatibility as well as good targeted capability was also expounded. Finally, challenges and new perspectives for designing effective inorganic nanomaterial-based nanosystems for photothermal assisted therapy were also discussed.