CuO Nanozymes Catalyze Cysteine and Glutathione Depletion Induced Ferroptosis and Cuproptosis for Synergistic Tumor Therapy.

The latest research identifies that cysteine (Cys) is one of the key factors in tumor proliferation, metastasis, and recurrence. The direct depletion of intracellular Cys shows a profound antitumor effect. However, using nanozymes to efficiently deplete Cys for tumor therapy has not yet attracted widespread attention. Here, a (3-carboxypropyl) triphenylphosphonium bromide-derived hyaluronic acid-modified copper oxide nanorods (denoted as MitCuOHA) are designed with cysteine oxidase-like, glutathione oxidase-like and peroxidase-like activities to realize Cys depletion and further induce cellular ferroptosis and cuproptosis for synergistic tumor therapy. MitCuOHA nanozymes can efficiently catalyze the depletion of Cys and glutathione (GSH), accompanied by the generation of H2O2 and the subsequent conversion into highly active hydroxyl radicals, thereby successfully inducing ferroptosis in cancer cells. Meanwhile, copper ions released by MitCuOHA under tumor microenvironment stimulation directly bind to lipoylated proteins of the tricarboxylic acid cycle, leading to the abnormal aggregation of lipoylated proteins and subsequent loss of iron-sulfur cluster proteins, which ultimately triggers proteotoxic stress and cell cuproptosis. Both in vitro and in vivo results show the drastically enhanced anticancer efficacy of Cys oxidation catalyzed by the MitCuOHA nanozymes, demonstrating the high feasibility of such catalytic Cys depletion-induced synergistic ferroptosis and cuproptosis therapeutic concept.

Structure and Defect Engineering Synergistically Boost High Solar-to-Chemical Conversion Efficiency of Cerium oxide/Au Hollow Nanomushrooms for Nitrogen Photofixation.

Photocatalytic nitrogen fixation using solar illumination under ambient conditions is a promising strategy for production of the indispensable chemical NH3 . However, due to the catalyst's limitations in solar energy utilization, loss of hot electrons during transfer, and low nitrogen adsorption and activation capacity, the unsatisfactory solar-to-chemical conversion (SCC) efficiencies of most photocatalysts limit their practical applications. Herein, cerium oxide nanosheets with abundant strain-VO defects were anchored on Au hollow nanomushroom through atomically sharp interfaces to construct a novel semiconductor/plasmonic metal hollow nanomushroom-like heterostructure (denoted cerium oxide-AD/Au). Plasmonic Au extended the absorption of light from the visible to the second near-infrared region. The superior interface greatly enhanced the transfer efficiency of hot electrons. Abundant strain-VO defects induced by interfacial compressive strain promoted adsorption and in situ activation of nitrogen, and such synergistic promotion of strain and VO defects was further confirmed by density functional theory calculations. The judicious structural and defect engineering co-promoted the efficient nitrogen photofixation of the cerium oxide-AD/Au heterostructures with a SCC efficiency of 0.1 % under simulated AM 1.5G solar illumination, which is comparable to the average solar-to-biomass conversion efficiency of natural photosynthesis by typical plants, thus exhibiting significant potential as a new candidate for artificial photosynthesis.

Fabrication of Supramolecular System Derived from Poly ß-cyclodextrin Coupling Quinoline Dderivative and Its Fluorescence Sensing of Zinc Ion in Pure Water Environment.

Cyclodextrin (CD) is an important guest material owing to the water solubility and biocompatibility. In the paper, an organic small molecule was synthesized. According to supramolecular self-assembly, the organic molecule was bounded to the cavity of Poly ß-cyclodextrin, which was characterized by IR, SEM and TEM et al. After self-assembly interaction, the morphology has changed obviously comparing with precursors. Simultaneously, the supramolecular self-assembly complex exhibited good water solubility. Moreover, By Gaussian calculation, the high binding activity between organic molecule and cyclodextrin was confirmed. By fluorescence investigation, the supramolecular system showed high fluorescence sensing activity for Zn2+ in pure water environment, which could track the dynamic change of Zn2+ in organisms. In addition, the supramolecular system exhibited low cytotoxicity. The work provided an interesting pathway for constructing water-soluble and low cytotoxic fluorescence sensor for Zn2+.

Simultaneous Sensing of H2S and ATP with a Two-Photon Fluorescent Probe in Alzheimer's Disease: toward Understanding Why H2S Regulates Glutamate-Induced ATP Dysregulation.

Energy deprivation and reduced levels of hydrogen sulfide (H2S) in the brain is closely associated with Alzheimer's disease (AD). However, there is currently no fluorescent probe for precise exploration of both H2S and adenosine triphosphate (ATP) to directly demonstrate their relationship and their dynamic pattern changes. Herein, we developed a two-photon fluorescent probe, named AD-3, to simultaneously image endogenous H2S and ATP from two emission channels of fluorescent signals in live rat brains with AD. The probe achieved excellent selectivity and good detection linearity for H2S in the 0-100 µM concentration range and ATP in the 2-5 mM concentration range, respectively, with a detection limit of 0.19 µM for H2S and 0.01 mM for ATP. Fluorescence imaging in live cells reveals that such probe could successfully apply for simultaneous imaging and accurate quantification of H2S and ATP in neuronal cells. Further using real-time quantitative polymerase chain reaction and Western blots, we confirmed that H2S regulates ATP synthesis by acting on cytochrome C, cytochrome oxidase subunit 3 of complex IV, and protein 6 of complex I in the mitochondrial respiratory chain. Subsequently, we constructed a high-throughput screening platform based on AD-3 probe to rapidly screen the potential anti-AD drugs to control glutamate-stimulated oxidative stress associated with abnormal H2S and ATP levels. Significantly, AD-3 probe was found capable of imaging of H2S and ATP in APP/PS1 mice, and the concentration of H2S and ATP in the AD mouse brain was found to be lower than that in wild-type mice.

NIR II Light-Response Au Nanoframes: Amplification of a Pressure- and Temperature-Sensing Strategy for Portable Detection and Photothermal Therapy of Cancer Cells.

Quantitative detection of cancer cells using portable devices is promising for the development of simple, fast, and point-of-care cancer diagnostic techniques. However, how to further amplify the detection signal to improve the sensitivity and accuracy of detecting cancer cells by portable devices remains a challenge. To solve the problem, we, for the first time, synthesized folic-acid-conjugated Au nanoframes (FA-Au NFs) with amplification of pressure and temperature signals for highly sensitive and accurate detection of cancer cells by portable pressure meters and thermometers. The resulting Au NFs exhibit excellent near-infrared (NIR) photothermal performance and catalase activity, which can promote the decomposition of NH4HCO3 and H2O2 to generate corresponding gases (CO2, NH3, and O2), thereby synergistically amplifying pressure signals in a closed reaction vessel. At the same time, Au NFs with excellent peroxidase-like activity can catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to produce TMB oxide (oxTMB) with a strong photothermal effect, thereby cooperating with Au NFs to amplify the photothermal signal. In the presence of cancer cells with overexpressing folate receptors (FRs), the molecular recognition signals between FA and FR can be converted into amplified pressure and temperature signals, which can be easily read by portable pressure meters and thermometers, respectively. The detection limits for cancer cells using pressure meters and thermometers are 6 and 5 cells/mL, respectively, which are better than other reported methods. Moreover, such Au NFs can improve tumor hypoxia by catalyzing the decomposition of H2O2 to produce O2 and perform photothermal therapy of cancer. Together, our work provides new insight into the application of Au NFs to develop a dual-signal sensing platform with amplification of pressure and temperature signals for portable and ultrasensitive detection of cancer cells as well as personalized cancer therapy.

Nitrogen-Doped Chiral CuO/CoO Nanofibers: An Enhanced Electrochemiluminescence Sensing Strategy for Detection of 3,4-Dihydroxy-Phenylalanine Enantiomers.

l-3,4-Dihydroxy-phenylalanine (l-DOPA) is the most effective drug for the treatment of Parkinson's disease, which plays a very important role in clinical and neurochemistry. However, how to achieve high-sensitivity recognition of l-DOPA still faces challenges. Here, a facile strategy is presented to construct nitrogen-doped chiral CuO/CoO nanofibers (N-CuO/CoO NFs) with nanozyme activity and electrochemiluminescence property, in which CuO/CoO NFs are used as the catalytic activity center and chiral cysteine (Cys) is used as the inducer of chiral recognition, for enantioselective catalysis and sensitive recognition of DOPA enantiomers. Notably, N doping not only enhances the enzyme-mimic activity of CuO/CoO NFs but also amplifies their electrochemiluminescence (ECL) signals in the presence of luminol. More importantly, in the presence of DOPA enantiomers, the d-cysteine (d-Cys)-modified N-CuO/CoO NFs exhibit different ECL performances; thus, d-Cys@N-CuO/CoO NFs could selectively distinguish and sensitively detect l-DOPA through ECL signals, and the detection limit is 0.29 nM for l-DOPA. In addition, it also showed good sensing performance for the determination of l-DOPA in fetal bovine serum. This is the first report on the detection of DOPA enantiomers based on an enhanced ECL strategy, providing a robust pathway for chiral discrimination and detection of chiral molecules.

Anisotropic Evaporator with a T-Shape Design for High-Performance Solar-Driven Zero-Liquid Discharge.

Solar-driven evaporation is regarded as a sustainable wastewater treatment strategy for clean water recovery and salt condensation. However, achieving both high evaporation rate and long-term stability remain challenging due to poor thermal management and rapid salt accumulation and blocking. Here, a T-shape solar-driven evaporator, composed of a surface-carbonized longitudinal wood membrane (C-L-wood) is demonstrated as the top "" for solar harvesting/vapor generation/salt collection and another piece of natural L-wood as the support "" for brine transporting and thermally insulating. The horizontally aligned micro-channels of C-L-wood have a low perpendicular thermal conductivity and can effectively localize the thermal energy for rapid evaporation. Meanwhile, the brine is guided to transport from the support L-wood ("") to the centerline of the top evaporator and then toward the double edge (""), during which clean water is evaporated and salt is crystallized at the edge. The T-shape evaporator demonstrates a high evaporation rate of 2.43 kg m-2 h-1 under 1 sun irradiation, and is stable for 7 days of the outdoor operation, which simultaneously realizes clean water evaporation and salt collection (including Cu2+ , CrO42- , Co2+ ), and achieves zero-liquid discharge. Therefore, the T-shape design provides an effective strategy for high performance wastewater treatment.

Enhanced Thermometric Sensor for Arsenate Analysis Based on Dual Temperature Readout Signaling Strategy.

New methods for portable detection of arsenate are still in urgent need. Herein, we explored a simple but sensitive thermometric strategy for arsenate determination without complex instruments and skilled technicians. Cobalt oxyhydroxide (CoOOH) nanoflakes, can ingeniously decompose hydrogen peroxide into oxygen in a sealed reaction vessel, accompanied by marked pressure and significant temperature increase due to the exothermic reaction effect (ΔH = -98.2 kJ/mol). The increased pressure then compelled a certain amount of H2O overflowing from the drainage device into another vessel, leading to a significant temperature decrease due to the preloaded ammonium nitrate (NH4NO3) and its good dissolution endothermic effect (ΔH = 25.4 kJ/mol). In the presence of arsenate, the catalytic activity of CoOOH nanoflakes for H2O2 decomposition was inhibited dramatically, resulting in an obvious decrease of the pressure, weighting water and temperature response. The two temperature responses with increasing and decreasing feature were easily measured through a common thermometer, and exhibited an effective signaling amplification via coupling both "signal-on" and "signal-off" temperature readout elements. The obtained dual superimposing temperature readout exhibits a good linear with the concentration of arsenate with a lower detection limit (51 nM, 3.8 ppb). Compared to the inductively coupled plasma mass spectrometry, this enhanced thermometric strategy provides a simple, rapid, convenient, low cost, and portable platform for sensing arsenate in real environmental water.

Palladium Coordination Polymers Nanosheets: New Strategy for Sensitive Photothermal Detection of H2S.

New strategies for portable detection of highly toxic environmental pollutants are still in urgent need. Here, through Pd2+ and methylene blue (MB) coordination, photothermal two-dimensional palladium coordination polymers nanosheets (2D PdCPsNSs) have been synthesized for sensitive photothermal detection of H2S. The sensing mechanism is based on the decomposing effect of H2S to 2D PdCPsNSs, accompanied by the decrease of PdCPsNSs concentration and the increase of MB concentration. Upon H2S addition, the heat released from the 2D PdCPsNSs under 808 nm lasers irradiation decreased, and the heat released from the MB increased under 650 nm lasers irradiation, respectively. Such temperature change signals could be easily detected by a portable thermometer. The 2D PdCPsNSs showed highly sensitive ratiometric response to H2S with a detection limit of 30 nM. In addition, such probe presents an excellent selective ratiometric response to H2S relative to other anionic species and thiols because of the specific interaction between Pd2+ and H2S. Moreover, the probe was suitable for the ratiometric determination of H2S in different actual water samples, providing a promising platform for convenient, stable, and universal analysis of H2S.

In Situ Growth of Metal-Organic Frameworks in Three-Dimensional Aligned Lumen Arrays of Wood for Rapid and Highly Efficient Organic Pollutant Removal.

Organic contaminants in water have become one of the most serious environmental problems worldwide. Adsorption is one of the most promising approaches to remove organic pollutants from water. However, the existing adsorbents have relatively low removal efficiency, complex preparation processes, and high cost, which limit their practical applications. Here, we developed three-dimensional (3D) zirconium metal-organic frameworks (MOFs) encapsulated in a natural wood membrane (UiO-66/wood membrane) for highly efficient organic pollutant removal from water. UiO-66 MOFs were in situ grown in the 3D low-tortuosity wood lumens by a facile solvothermal strategy. The resulting UiO-66/wood membrane contains the highly mesoporous UiO-66 MOF structure as well as many elongated and open lumens along the direction of the wood growth. Such a unique structural feature improves the mass transfer of organic pollutants and increases the contact probability of organic contaminants with UiO-66 MOFs as the water flows through the membrane, thereby improving the removal efficiency. Furthermore, the integrated multilayer filter consisting of three pieces of UiO-66/wood membranes exhibits a high removal efficiency (96.0%) for organic pollutants such as rhodamine 6G, propranolol, and bisphenol A at the flux of 1.0 × 103 L·m-2·h-1. The adsorbed capacity of UiO-66/wood for Rh6G (based on the content of UiO-66 MOFs) is calculated to be 690 mg·g-1. We believe that such low-cost and scalable production of the UiO-66/wood membrane has broad applications for wastewater treatment and other related pollutant removal.

Porous Wood Members-Based Amplified Colorimetric Sensor for Hg2+ Detection through Hg2+-Triggered Methylene Blue Reduction Reactions.

Wood has attracted increasing scientific interest in the field of green electronics, biological devices, bioenergy, and energy storage because of its abundance, low cost, biocompatibility, and natural vessel structure. However, its potential application in the important area of environmental monitoring has not yet been effectively explored. In this work, gold nanoparticles (NPs) encapsulated in porous wood (denoted as Au@wood) for high-performance colorimetric detection of Hg2+ in aqueous solution have been constructed. The detection mechanism is based on Hg2+-triggered methylene blue (MB) reduction-assisted signal amplification. In such a detection system, Au NPs can be used as a specific identification element for the binding of Hg2+ due to the formation of gold amalgam to initiate catalytic activity of gold. The low-cost natural wood is introduced to prevent the aggregation of Au NPs and increase the contact area between MB and Au NPs in three-dimensional space. MB, as a tracer molecule, enables the output signals to be directly observed by the naked eye. Such a detection system exhibited an ultralow detection limit of 32 pM for Hg2+, which is greatly lower than the threshold levels (10 nM) for drinking water and other colorimetric methods. The proposed detection system also exhibits high selectivity against other metal ions and works well for environmental water and blood samples. The resultant Au@wood sensor is low cost, easy handling, and convenient, making it an attractive material for point-of-use monitoring of Hg2+ in environmental and biological samples.

Hyper-Cross-linked Porous MoS2-Cyclodextrin-Polymer Frameworks: Durable Removal of Aromatic Phenolic Micropollutant from Water.

A reasonable and efficient strategy for the construction of hyper-cross-linked porous MoS2-CD-polymer frameworks (MoS2CDPFs) was demonstrated. Here, MoS2 nanosheets (NSs) can be decorated with amino functionalized ß-cyclodextrin, producing a nanoscale structural motif (MoS2@CD) for the synthesis of MoS2CDPFs. We demonstrated that CD polymer (CDP) as linker can be uniformly incorporated into the frameworks. Except for the pores created between MoS2 NSs, polymer doping generates extra interspace between MoS2 NSs and CD monomer. Interestingly, the resultant MoS2CDPFs can rapidly sequester aromatic phenolic micropollutant bisphenol A (0.1 mM) from water with 93.2% adsorption capacity, which is higher than that of MoS2, MoS2@CD, and CDP. The intercalation between MoS2 sheets with CDP imparts the frameworks durability in adsorption/desorption of aromatic phenolic micropollutants. Remarkably, the removal efficiency reduced only 3% after 10 regeneration-reuse cycles. These findings demonstrated that the porous MoS2-CD-polymer-based frameworks are promising adsorbents for rapid, flow-through water remediation.

Reversible Response of Luminescent Terbium(III)-Nanocellulose Hydrogels to Anions for Latent Fingerprint Detection and Encryption.

Fingerprint fluorescence imaging has become one of the most prominent technologies in the field of forensic medicine, but it seldom considers the security protection of detection information, which is of great importance in modern society. Herein we demonstrate that luminescent TbIII -carboxymethyl cellulose (CMC) complex binding aptamer hydrogels that are reversibly responsive to ClO- /SCN- can be used for the selective detection, protection, and storage of fingerprint information. The imaging information of the fingerprint can be quenched and recovered by ClO- /SCN- regulation, respectively, resulting in reversible on/off conversion of the luminescence signals for the encryption and decryption of multiple levels of information. The present study opens new avenues for multilevel imaging, data recording, and security protection of fingerprint information with tunable fluorescent hydrogels.

Photocatalysis-Based Nanoprobes Using Noble Metal-Semiconductor Heterostructure for Visible Light-Driven in Vivo Detection of Mercury.

The development of sensitive and reliable methods to monitor the presence of mercuric ions in cells and organisms is of great importance to biological research and biomedical applications. In this work, we propose a strategy to construct a solar-driven nanoprobe using a 3D Au@MoS2 heterostructure as a photocatalyst and rhodamine B (RB) as a fluorescent and color change reporter molecule for monitoring Hg2+ in living cells and animals. The sensing mechanism is based on the photoinduced electron formation of gold amalgam in the 3D Au@MoS2 heterostructure under visible light illumination. This formation is able to remarkably inhibit the photocatalytic activity of the heterostructure toward RB decomposition. As a result, "OFF-ON" fluorescence and color change are produced. Such characteristics enable this new sensing platform to sensitively and selectively detect Hg2+ in water by fluorescence and colorimetric methods. The detection limits of the fluorescence assay and colorimetric assay are 0.22 and 0.038 nM for Hg2+, respectively; these values are well below the acceptable limits in drinking water standards (10 nM). For the first time, such photocatalysis-based sensing platform is successfully used to monitor Hg2+ in live cells and mice. Our work therefore opens a promising photocatalysis-based analysis methodology for highly sensitive and selective in vivo Hg2+ bioimaging studies.

Efficient Hydrogen-Generation CuO/Co3O4 Heterojunction Nanofibers for Sensitive Detection of Cancer Cells by Portable Pressure Meter.

Portable, low-cost, and quantitative detection of cancer cells at home and in the field has the potential to revolutionize medical diagnostics. We first report the design and synthesis of highly efficient folic-acid-conjugated hydrogen-generation tube-in-tube CuO/Co3O4 heterojunction nanofibers for highly sensitive and rapid recognition of cancer cells through a pressure signal under visible-light irradiation. The resultant nanofibers can dramatically enhance the hydrogen-generation activity of ammonia borane under visible-light irradiation. Such hydrogen-generation reaction can translate a molecular recognition event between folic acid and folate receptor to measurable pressure signal readout through a low-cost and portable pressure meter for target cancer cell detection. Limits of detection (LODs) down to 50 cells mL-1 in only 15 min can be achieved. This result is superior to those of the other reported methods, indicating the superiority of the new pressure-based sensor in terms of sensitivity. The present study establishes the pressure meter as a useful tool for early clinical point-of-care cancer diagnosis.

Soluble Porous Coordination Frameworks Constructed from Inorganic Nanoparticles as Homogenized Heterogeneous Photocatalysts for Suzuki Coupling Reactions under Near-Infrared Light.

Self-assembly has emerged as a promising method to control the structure and properties of ensembles of inorganic nanoparticles (NPs) for exploiting their collective effects. However, the rational assembly of inorganic NPs into soluble porous architectures for use as homogenized heterogeneous catalysts has been less studied. Herein, it is shown that inorganic NPs can be used for the assembly of soluble porous coordination frameworks (PCFs) by atom-scale interfacial coordination-driven assembly. Owing to their large pore size, high dispersity in solution, strong absorption in the near-infrared (NIR) range, and long-lived electron-hole pair, the obtained soluble frameworks could serve as a platform for homogenized heterogeneous photocatalysts, which exhibited excellent activity, high apparent quantum efficiency, and recyclability in the catalysis of the noble-metal-free Suzuki coupling reactions under NIR light at room temperature. Moreover, PCF catalysts can be reused more than five times without significant loss of activity, which indicates long-term stability. The present strategy to fabricate soluble porous nanostructures opens a new chemical toolbox for homogenized heterogeneous catalysts and may bring new inspiration to photocatalysis.

A Chromone-Derived Schiff-Base Ligand as Al(3+) "Turn on" Fluorescent Sensor: Synthesis and Spectroscopic Properties.

In this study, a novel chromone-derived Schiff-base ligand called 6-Hydroxy-3-formylchromone (2'-furan formyl) hydrazone (HCFH) has been designed and synthesized as a "turn on" fluorescent sensor for Al(3+). This sensor HCFH showed high selectivity and sensitivity towards Al(3+) over other metal ions investigated, and most metal ions had nearly no influences on the fluorescence response of HCFH to Al(3+). Additionally, the significant enhancement by about 171-fold in fluorescence emission intensity at 502 nm was observed in the presence of Al(3+) in ethanol, and it was due to the chelation-enhanced fluorescence (CHEF) effect upon complexation of HCFH with Al(3+) which inhibited the photoinduced electron transfer (PET) phenomenon from the Schiff-base nitrogen atom to chromone group. Moreover, this sensor formed a 1 : 1 complex with Al(3+) and the fluorescence response of HCFH to Al(3+) was nearly completed within 1 min. Thus, this sensor HCFH could be used to detect and recognize Al(3+) for real-time detection.

Triple-Emitting Dumbbell Fluorescent Nanoprobe for Multicolor Detection and Imaging Applications.

The combination of different fluorescent species into one nanostructure to develop fluorescent nanoparticles with multiple emission signatures by a single wavelength excitation has become a very popular research area in the field of multiplex bioanalysis, diagnostics, and multicolor imaging. However, these novel hybrids must be elaborately designed to ensure that the unique properties of each component are conveyed, i.e., fluorescent species and nanoparticles, and are maximized without serious interactions with each other. Herein, a first triple-fluorescence dumbbell nanoprobe with large Stokes shift based on incorporating fluorescein isothiocyanate (FITC) and lanthanide complexes onto Au-Fe3O4 NPs was synthesized. This hybrid displays well-resolved triple fluorescence emission, with FITC at 515 nm, Tb(III) complex at 545 nm, and Eu(III) complex at 616 nm under a single-excitation wavelength and is used for highly selective and sensitive colorimetric detection of Cu(2+) with a detection limit of 30 nM. Under different Cu(2+) concentrations, this hybrid exhibited distinguishable multiple colors under UV light, and the color could change in the presence of different concentrations of Cu(2+). This sensor for ratio/multianalyte microscopic imaging of Cu(2+) in HeLa cells and BHK cells was also demonstrated. Target molecules, such as folic acid, can be covalently attached to the fluorescent nanoparticle surface to serve as an effective probe for simultaneous multicolor imaging folate receptor-overexpressing HeLa cell lines in vitro.

Palladium nanoparticles bonded to two-dimensional iron oxide graphene nanosheets: a synergistic and highly reusable catalyst for the Tsuji-Trost reaction in water and air.

Low cost, high activity and selectivity, convenient separation, and increased reusability are the main requirements for noble-metal-nanocatalyst-catalyzed reactions. Despite tremendous efforts, developing noble-metal nanocatalysts to meet the above requirements remains a significant challenge. Here we present a general strategy for the preparation of strongly coupled Fe(3)O(4) and palladium nanoparticles (PdNPs) to graphene sheets by employing polyethyleneimine as the coupling linker. Transmission electron microscopic images show that Pd and Fe(3)O(4) nanoparticles are highly dispersed on the graphene surface, and the mean particle size of Pd is around 3 nm. This nanocatalyst exhibits synergistic catalysis by Pd nanoparticles supported on reduced graphene oxide (rGO) and a tertiary amine of polyethyleneimine (Pd/Fe(3)O(4)/PEI/rGO) for the Tsuji-Trost reaction in water and air. For example, the reaction of ethyl acetoacetate with allyl ethyl carbonate afforded the allylated product in more than 99 % isolated yield, and the turnover frequency reached 2200 h(-1). The yield of allylated products was 66 % for Pd/rGO without polyethyleneimine. The catalyst could be readily recycled by a magnet and reused more than 30 times without appreciable loss of activity. In addition, only about 7.5 % of Pd species leached off after 20 cycles, thus rendering this catalyst safer for the environment.

Photodynamic O2 Economizer Encapsulated with DNAzyme for Enhancing Mitochondrial Gene-Photodynamic Therapy.

Emerging research suggests that mitochondrial DNA is a potential target for cancer treatment. However, achieving precise delivery of deoxyribozymes (DNAzymes) and combining photodynamic therapy (PDT) and DNAzyme-based gene silencing together for enhancing mitochondrial gene-photodynamic synergistic therapy remains challenging. Accordingly, herein, intelligent supramolecular nanomicelles are constructed by encapsulating a DNAzyme into a photodynamic O2 economizer for mitochondrial NO gas-enhanced synergistic gene-photodynamic therapy. The designed nanomicelles demonstrate sensitive acid- and red-light sequence-activated behaviors. After entering the cancer cells and targeting the mitochondria, these micelles will disintegrate and release the DNAzyme and Mn (II) porphyrin in the tumor microenvironment. Mn (II) porphyrin acts as a DNAzyme cofactor to activate the DNAzyme for the cleavage reaction. Subsequently, the NO-carrying donor is decomposed under red light irradiation to generate NO that inhibits cellular respiration, facilitating the conversion of more O2 into singlet oxygen (1 O2 ) in the tumor cells, thereby significantly enhancing the efficacy of PDT. In vitro and in vivo experiments reveal that the proposed system can efficiently target mitochondria and exhibits considerable antitumor effects with negligible systemic toxicity. Thus, this study provides a useful conditional platform for the precise delivery of DNAzymes and a novel strategy for activatable NO gas-enhanced mitochondrial gene-photodynamic therapy.