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Advanced application of the superwettable surface with intelligent stimulus-responsive property invents a new way for designing controllable and effective oil-water separation material. Here, a smart superwettable fabric with tunable wettability has been fabricated via a low-cost and eco-friendly approach. With synergistic effect of the well-define micro/nano-hierarchical structure and pH-sensitive undecylenic acid, the as-prepared superwettable coating exhibits an excellent switchable surface wettability, which can reversibly transit between superhydrophobicity and superhydrophilicity in accordance with pH values of the contacting aqueous water. By virtue of the special wetting property, the obtained superwettable coating can be exploited to controllably and efficiently separate various oil-water mixtures, showing attractive separation efficiency (99 %) and favorable durability. Moreover, the complex oil/water/oil three-phase system also can be successfully separated with the superwettable coating as separation membrane, revealing an excellent in situ pH-responsiveness. Besides, it is worth noting that the superwettable coating is competent to selectively remove organic from oil, which has been seldom reported in previous works and providing a viable strategy for separating organic from oil. In light of the above advantages, it is believed that the functionalized smart coating with controllable tunable surface wettability will be a promising candidate for oily wastewater remediation under various harsh settings.

Chaos and the natural evolution of tumor systems can lead to the failure of tumor therapies. Herein, we demonstrate that iridium oxide nanoparticles (IrOx ) possess acid-activated oxidase and peroxidase-like functions and wide pH-dependent catalase-like properties. The integration of glucose oxidase (GOD) unlocked the oxidase and peroxidase activities of IrOx by the production of gluconic acid from glucose by GOD catalysis in cancer cells, and the produced H2 O2 was converted into O2 to compensate its consumption in GOD catalysis owing to the catalase-like function of the nanozyme, thus resulting in the continual consumption of glucose and the self-supply of substrates to generate superoxide anion and hydroxyl radical. Moreover, IrOx can constantly consume glutathione (GSH) by self-cyclic valence alternation of IrIV and IrIII . These cascade reactions lead to a "butterfly effect" of initial starvation therapy and the subsequent pressure of multiple reactive oxygen species (ROS) to completely break the self-adaption of cancer cells.

For many two-dimensional (2D) materials, low coordination edges and corner sites offer greatly enhanced catalytic performance compared to basal sites, motivating the search for new synthetic approaches towards ultrathin and ultrafine 2D nanomaterials with high specific surface areas. To date, the synthesis of catalysts that are both ultrathin (monolayer) and ultrafine (lateral size

The generation of singlet oxygen (1 O2 ) during photodynamic therapy is limited by the precise cooperation of light, photosensitizer, and oxygen, and the therapeutic efficiency is restricted by the elevated glutathione (GSH) levels in cancer cells. Herein, we report that an ultrathin two-dimensional metal-organic framework of Cu-TCPP nanosheets (TCPP=tetrakis(4-carboxyphenyl)porphyrin) can selectively generate 1 O2 in a tumor microenvironment. This process is based on the peroxidation of the TCPP ligand by acidic H2 O2 followed by reduction to peroxyl radicals under the action of the peroxidase-like nanosheets and Cu2+ , and their spontaneous recombination reaction by the Russell mechanism. In addition, the nanosheets can also deplete GSH. Consequently, the Cu-TCPP nanosheets can selectively destroy tumor cells with high efficiency, constituting an attractive way to overcome current limitations of photodynamic therapy.

As the semisynthetic derivative and active metabolite of the effective anti-malarial drug artemisinin, dihydroartemisinin (DHA) has been investigated as an emerging therapeutic agent for tumor treatment based on the cytotoxicity of free-radicals originating from interactions with ferrous ions. Meanwhile, simultaneously delivering DHA and iron ions to tumors for selectively killing cancer cells is still a great challenge in DHA tumor therapy. Herein, we develop a facile yet efficient strategy based on iron-coordinated hollow polydopamine nanospheres to load DHA (DHA@HPDA-Fe). The as-prepared nanoagent is biodegradable and exhibits controllable release of DHA and Fe ions in tumor microenvironments, resulting in ferrous ion-enhanced production of cytotoxic reactive oxygen species (ROS) by DHA and thus effectively killing the tumor cells. In vivo therapy experiments indicated that the anti-tumor efficacy of DHA@HPDA-Fe was about 3.05 times greater than that of free DHA, and the tumor inhibition ratio was 88.7% compared with the control group, accompanied by negligible side effects, indicating that the proposed nanomedicine platform is promising for anti-tumor applications.

Phototherapy, including photothermal therapy (PTT)/photodynamic therapy (PDT), is usually considered as a promising strategy for cancer treatment due to its noninvasive and selective therapeutic effect by laser irradiation. A light-activatable nanoplatform based on bovine serum albumin (BSA)-coated Bi2Te3 nanosheets conjugated with methylene blue (MB) was successfully designed and constructed for bimodal PTT/PDT combination therapy. The resultant nanoconstruct (BSA-Bi2Te3/MB) exhibited high stability in various physiological solutions and excellent biocompatibility. Especially, the nanoconstruct not only possessed strong near-infrared absorption and high photothermal conversion as a photothermal agent for efficient tumor ablation but also could successfully load photosensitizer for PDT of tumor. When exposed to laser irradiation, tumors in mice with BSA-Bi2Te3/MB injection were completely eliminated without recurrence within 15 d, demonstrating the potential of the nanoconstruct as a bimodal PTT/PDT thera...

Intrinsically integrating precise diagnosis, effective therapy, and self-anti-inflammatory action into a single nanoparticle is attractive for tumor treatment and future clinical application, but still remains a great challenge. In this study, bovine serum albumin-iridium oxide nanoparticles (BSA-IrO2 NPs) with extraordinary photothermal conversion efficiency, good photocatalytic activity, and a high X-ray absorption coefficient were prepared through one-step biomineralization. The nanoparticles allow tumor phototherapy and simultaneous photoacoustic/thermal imaging and computed tomography. More importantly, BSA-IrO2 NPs can also act as a catalase to protect normal cells against H2 O2 -induced reactive oxygen pressure and inflammation while significantly enhancing photoacoustic imaging through microbubble-based inertial cavitation. These remarkable features may open up the exploration iridium-based nanomaterials in theranostics.

The local tumor hypoxia has become one of the main obstacles for photodynamic therapy (PDT).To break through this barrier, the fabrication of O2-evolving nanoplatform has been more significant. Herein, the uniform methylene blue (MB)–bovine serum albumin (BSA)–Fe(III) nanoparticles (MB–BSA–Fe(III) NPs) were successfully synthesized by biomineralization approach. MB–BSA–Fe(III) NPs show high loading capacity of MB, and Fe(ΙΙΙ) has excellent catalytic performance towards abundant H2O2 in cancer cells to generate O2, overcoming tumor hypoxia. All these combination effects remarkably increase the therapeutic efficiency of PDT, resulting in almost complete destruction of cancer cells. Most importantly, MB–BSA–Fe(III) NPs exhibit T2- magnetic resonance imaging, which have the potential for precise visualization of the tumor location. Our results demonstrate that MB–BSA–Fe(III) is a novel H2O2-responsive and O2-evolving nanoplatform and it has great potential for clinical applications such as cancer diagnosis, treatment or drug delivery.

Integration of multiple therapeutic/diagnostic modalities into a single system holds great promise to improve theranostic efficiency for tumors, but still remains a technical challenge. Herein, we report a new multimodal theranostic nanoconstruct based on Fe-doped polydiaminopyridine nanofusiforms, built easily and on a large scale, which can dual-regulate intracellular oxygen and glutathione levels, transport iron ions, and simultaneously be used for thermal imaging and magnetic resonance imaging. Co-loading of dihydroartemisinin and methylene blue generates a superior multifunctional theranostic agent with enhanced photochemotherapy efficiency and biodegradability, leading to almost complete destruction of tumors with near-infrared light irradiation. This represents an attractive route to develop multimodal anticancer theranostics.

In this study, we present the synthesis and application of a new therapeutic platform based on photosensitizer-loaded, two-dimensional layered nanomaterials of WSe2 for combined photothermal and photodynamic cancer therapy. WSe2 nanosheets are synthesized by a simple and efficient chemical exfoliation using bovine serum albumin (BSA) as an effective exfoliating agent and strong stabilizing agent, endowing the WSe2-BSA nanosheets obtained with high stability in physiological solutions and good biocompatibility without further functionalization. The WSe2-BSA nanosheets can be employed not only as an efficient photothermal agent but also as a carrier to load methylene blue (MB) as a photosensitizing agent for photodynamic therapy. Moreover, the generation of singlet oxygen can be regulated by controlling the release of MB from the WSe2 nanosheets with NIR irradiation. The therapeutic efficacy of the MB-loaded WSe2-BSA (WSe2-BSA/MB) complexes was evaluated in vitro and in vivo. It was found that dual-mode photothermal and photodynamic therapy has a significant synergistic effect and dramatically improves the therapeutic efficacy toward cancer cells compared with single mode treatment. These findings indicate that WSe2 nanosheets could be a promising therapeutic agent and smart carrier for the synergistic combination of phototherapy towards biomedical applications.

At present, increasing attention is being paid to photothermal therapy corresponding to the second near infrared (NIR-II) range (1000–1700 nanometers); however, its biomedical applications related to carbon-based nanomaterials (CNMs) have always been limited by the large-scale fabrication of excellent diagnostic probes with a suitable size and optical absorption cross-section. Herein, we successfully prepared Bi@C nanoparticles with a suitable size and high output (3.14 g per patch) through a one-pot hydrothermal method. By combining Bi with carbon, the optical absorption in the NIR-II range was enhanced compared to that for single carbon; moreover, Bi@C could no longer be easily oxidized due to the protection of outer C compared with individual Bi. Furthermore, because of the high atomic number of Bi (Z = 83), the Bi@C nanoparticles exhibited computed imaging contrast properties. According to the in vitro and in vivo experiments, the Bi@C nanoparticles could ablate cancer cells under illumination with a 1064 nm laser with deeper penetration and an appropriate permissible exposure (MPE) to the laser (1 W cm−2), showing excellent performance for the diagnosis and treatment of tumors. This study provides a simple method to synthesize metal–carbon nanocomposites to enhance the NIR-II optical absorption efficiency for effective deep-seated tumor photothermal therapy and will further broaden the applications of CNMs.

This study reports the synthesis of ultrafine NiFe-layered double hydroxide (NiFe-LDH) nanosheets, possessing a size range between 1.5 and 3.0 nm with a thickness of 0.6 nm. Abundant metal and oxygen vacancies impart the ultrafine nanosheets with semi-metallic character, and thus superior charge transfer properties and electrochemical water oxidation performance with overpotentials (η) of 254 mV relative to monolayer LDH nanosheets (η of 280 mV) or bulk LDH materials (η of 320 mV) at 10 mA cm−2. These results are highly encouraging for the future application of ultrafine monolayer LDH nanosheets in electronics, solar cells, and catalysis.

Recently, two-dimensional transition metal dichalcogenides (TMDCs) have been widely studied in biomedicine. In this article, we developed a new photothermal nanocarrier based on polydopamine coated selenide molybdenum (MoSe2@PDA) as an effective nanocarrier for loading anticancer drug doxorubicin (MoSe2@PDA-Dox). Conjugation of PDA onto the surface of MoSe2 nanosheets can not only enhance the photothermal effect of MoSe2 nanosheets and decrease its cytotoxicity but also provide anchor points for loading Dox. The resulting MoSe2@PDA nanocomposites exhibit good biocompatibility, good stability, and high photothermal conversion efficiency. The subsequent loading of anticancer drug doxorubicin (Dox) creates an efficient therapeutic agent with pH- and heat-responsive drug release. An in vivo experiment shows strong damage to tumor tissue, killing the tumor cell almost thoroughly. On that account, the MoSe2@PDA-Dox nanocomposites may play a key role in cancer therapy in the future. Our work reveals the great pr...

Local hypoxia in tumors, as well as the short lifetime and limited action region of 1 O2 , are undesirable impediments for photodynamic therapy (PDT), leading to a greatly reduced effectiveness. To overcome these adversities, a mitochondria-targeting, H2 O2 -activatable, and O2 -evolving PDT nanoplatform is developed based on FeIII -doped two-dimensional C3 N4 nanofusiform for highly selective and efficient cancer treatment. The ultrahigh surface area of 2D nanosheets enhances the photosensitizer (PS) loading capacity and the doping of FeIII leads to peroxidase mimetics with excellent catalytic performance towards H2 O2 in cancer cells to generate O2 . As such tumor hypoxia can be overcome and the PDT efficacy is improved, whilst at the same time endowing the PDT theranostic agent with an effective T 1 -weighted in vivo magnetic resonance imaging (MRI) ability. Conjugation with a mitochondria-targeting agent could further increase the sensitivity of cancer cells to 1 O2 by enhanced mitochondria dysfunction. In vitro and in vivo anticancer studies demonstrate an outstanding therapeutic effectiveness of the developed PDT agent, leading to almost complete destruction of mouse cervical tumor. This development offers an attractive theranostic agent for in vivo MRI and synergistic photodynamic therapy toward clinical applications.

Faceted NiO nanoparticles preferentially exposing high surface energy planes demand attention due to their excellent electrocatalytic properties. However, the activity of faceted NiO nanoparticles generally remains suboptimal due to their large lateral size and thickness, which severely limits the availability of coordinatively unsaturated active reactive edge and corner sites. Here, ultrafine NiO nanosheets with a platelet size of ∼4.0 nm and thickness (∼1.1 nm) stabilized by TiO2 were successfully prepared by calcination of a monolayer layered double hydroxide precursor. The ultrafine NiO nanosheets displayed outstanding performance in electrochemical water oxidation due to a high proportion of reactive NiO {110} facets, intrinsic Ni(3+) and Ti(3+) sites, and abundant interfaces, which act synergistically to promote H2O adsorption and facilitate charge-transfer.

Premature leakage of photosensitizer (PS) from nanocarriers significantly reduces the accumulation of PS within a tumor, thereby enhancing nonspecific accumulation in normal tissues, which inevitably leads to a limited efficacy for photodynamic therapy (PDT) and the enhanced systematic phototoxicity. Moreover, local hypoxia of the tumor tissue also seriously hinders the PDT. To overcome these limitations, an acidic H2O2-responsive and O2-evolving core–shell PDT nanoplatform is developed by using MnO2 shell as a switchable shield to prevent the premature release of loaded PS in core and elevate the O2 concentration within tumor tissue. The inner core SiO2-methylene blue obtained by co-condensation has a high PS payload and the outer MnO2 shell shields PS from leaking into blood after intravenous injection until reaching tumor tissue. Moreover, the shell MnO2 simultaneously endows the theranostic nanocomposite with redox activity toward H2O2 in the acidic microenvironment of tumor tissue to generate O2 and thus overcomes the hypoxia of cancer cells. More importantly, the Mn(ΙΙ) ion reduced from Mn(ΙV) is capable of in vivo magnetic resonance imaging selectively in response to overexpressed acidic H2O2. The facile incorporation of the switchable MnO2 shell into one multifunctional diagnostic and therapeutic nanoplatform has great potential for future clinical application.

An enormous research effort is currently being directed towards the development of efficient visible-light-driven photocatalysts for renewable energy applications including water splitting, CO2 reduction and alcohol photoreforming. Layered double hydroxide (LDH)-based photocatalysts have emerged as one of the most promising candidates to replace TiO2-based photocatalysts for these reactions, owing to their unique layered structure, compositional flexibility, controllable particle size, low manufacturing cost and ease of synthesis. By introducing defects into LDH materials through the control of their size to the nanoscale, the atomic structure, surface defect concentration, and electronic and optical characteristics of LDH materials can be strategically engineered for particular applications. Furthermore, through the use of advanced characterization techniques such as X-ray absorption fine structure, positron annihilation spectrometry, X-ray photoelectron spectroscopy, electron spin resonance, density-functional theory calculations, and photocatalytic tests, structure-activity relationships can be established and used in the rational design of high-performance LDH-based photocatalysts for efficient solar energy capture. LDHs thus represent a versatile platform for semiconductor photocatalyst development with application potential across the energy sector.