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Water scarcity is a major challenge facing agricultural production in China. Unconventional water resources such as reclaimed wastewater can be used as a complimentary resource for irrigation. However, reclaimed wastewater is rich in salt and its long-term use for irrigation could lead to secondary soil salinization. In this review, we analyze the factors that have potential effects on accumulation of salt in soil. They include irrigation method, soil texture, crop types and crop variety, irrigation time, and reclaimed wastewater modification. Results show that our current understanding of the effect of long-term reclaimed water irrigation on soil salt accumulation is still unclear. As a result, more systematic studies are needed to elucidate the main factors that affect salt accumulation in soil. While reclaimed water modification is promising, more studies are required before it can be widely implemented. We suggest that future research on reclaimed water irrigation should focus on field experiments to systematically study how irrigation method, soil texture, crops, agronomic management and reclaimed water modification interactively affect salt accumulation in soils irrigated with reclaimed wastewater.

MicroRNA‐21 (MiR‐21) has been confirmed to be upregulated in tumors, and its abnormal expression is closely associated with tumor occurrence. However, the traditional imaging methods are limited to qualitative imaging of miR‐21, and no effective strategy has been developed for monitoring its concentration in vivo during cancer initiation and progression. Herein, a biosensor is created utilizing a NIR‐II ratiometric fluorescent nanoprobe to quantitatively monitor dynamic alterations in miR‐21 levels in vivo. The nanoprobe (termed DCNP@DNA2@IR806) is constructed by introducing IR806 as a donor and down‐conversion nanoparticles (DCNP) as the acceptor, using DNA as linkers. Upon miR‐21‐responsive initiation of the nanoprobe, the 1550 nm fluorescent signal of DCNP stimulated by a 808 nm laser (F1550, 808Ex) increased because of the close proximity of IR806 to the DCNP and the subsequent non‐radiative energy transfer (NRET). Meanwhile, the 1550 nm fluorescent signal of DCNP stimulated by a 980 nm laser (F1550, 980Ex) remained stable because of the absence of NRET. This ratiometric NIR‐II fluorescent signal has been confirmed to be a reliable indicator of miR‐21 concentration in vivo. The strategy holds promise for further enhancing the understanding of microRNAs‐based molecular mechanisms underlying cancer progression, laying a foundation for the early diagnosis of microRNAs‐related diseases. [ABSTRACT FROM AUTHOR]

Ti3C2Tx MXene/CuxO composites were prepared by acid etching combined with electrochemical technique. The abundant active sites on the surface of MXene greatly increase the loading of CuxO nanoparticles, and the synergistic effect between the different components of the composite can accelerate the oxidation reaction of glucose. The results indicate that at the working potential of 0.55 V (vs. Ag/AgCl), the glucose sensor based on Ti3C2Tx MXene/CuxO composite presents large linear concentration ranges from 1 µM to 4.655 mM (sensitivity of 361 µA mM−1 cm−2) and from 5.155 mM to 16.155 mM (sensitivity of 133 µA mM−1 cm−2). The limit of detection is 0.065 µM. In addition, the sensor effectively avoids the oxidative interference of common interfering species such as ascorbic acid, dopamine and uric acid. The sensor has good reproducibility, stability and acceptable recoveries for the detection of glucose in human sweat sample (97.5-103.3%) with RSD values less than 4%. Based on these excellent properties it has great potential for the detection of glucose in real samples. [ABSTRACT FROM AUTHOR]

Real‐time monitoring the therapeutic process of sonodynamic therapy (SDT) is essential to optimize the treatment course in time and eventually improve the efficacy. The generation of singlet oxygen (1O2) is a quintessential characteristic of SDT, which permits non‐invasive monitoring of SDT by real‐time imaging of 1O2 inside the tumor. Nonetheless, the majority of probes are unable to measure 1O2 in real time because of its short half‐life and strong oxidative capacity. Here, the study constructs a ratiometric nanoplatform (DTPI) utilizing two fluorescent probes and the sonosensitizer TiO2. The poisonous 1O2 generated by DTPI following ultrasonic (US) radiation efficiently destroys tumor cells. The structural disruption of fluorescent dye IR‐1061 by 1O2 leads to a reduction in the DTPI fluorescence signal at 1100 nm, while US radiation has no impact on the fluorescence signal at 1550 nm. Thus, DTPI provides a precise and consistent reflection of the treatment efficacy at the tumor site, leveraging the ratiometric fluorescence signal and variations in oxygen content throughout the treatment process. This ratiometric‐fluorescence‐based reflection strategy establishes an effective and dependable platform for the real‐time monitoring and assessment of the cancer therapeutic effect through ratiometric probes. [ABSTRACT FROM AUTHOR]

The epitaxial organization of nano-objects with different compositions and structures into superlattice nanorods holds great promise for photocatalytic biomass oxidation as it can make full use of sunlight and improve carrier transport efficiency. Here, we construct type II photocatalytic heterojunctions using α-Fe2O3 and Nb2O5, both of which are alternately grown in situ to form superlattice nanorod structures. Due to the interlaced growth of thin layers of α-Fe2O3 and Nb2O5, the phase interface between α-Fe2O3 and Nb2O5 is greatly increased, which effectively improves the catalytic activity of the catalyst. The selective oxidation of HMF was achieved by superlattice α-Fe2O3/Nb2O5/C nanorod photoelectrocatalysts with 96.6% FDCA selectivity, which was 2.3 times higher than that of α-Fe2O3 and 3.5 times higher than that of Nb2O5, respectively, and the conversion of HMF was close to 100%. This work provides a new idea for the design of catalysts with superlattice structure and used for biomass conversion. [ABSTRACT FROM AUTHOR]

High hydrogen sulfide (H2S) expression has been shown to play a crucial role in tumor growth and proliferation in colon cancer. So far, most probes used for monitoring H2S offer single‐modal imaging, which makes the collection of accurate information for tumor diagnosis difficult. In the present study, a novel dual‐modal imaging probe in the second near‐infrared (NIR‐II, 950‐1700) window is proposed and constructed by coating a uniform shell of polydopamine (PDA) on the surface of cuprous oxide (Cu2O)‐conjugated downconversion nanoparticles (DCNPs). Of note, DCNP‐Cu2O@PDA is in the "on" state, with emission centered at 1550 nm (irradiation using a 980nm laser) in non‐neoplastic tissues. Colon tumors with endogenous H2S overexpression can induce the in situ transformation of Cu2O to copper sulfide (Cu2‐XS）. Owing to the competitive absorption between Cu2‐XS and DCNPs at a wavelength of 980 nm, the generated DCNP‐Cu2‐XS@PDA exhibits a quenched NIR‐II fluorescence (FL) signal. Meanwhile, Cu2‐XS exhibits a strong absorbance at 1250 nm, enhancing the NIR‐II photoacoustic (PA) signal accompanied by NIR‐II FL attenuation. The switching in PA and FL signals at the tumor site offered "double assurances" for the accurate monitoring of H2S. [ABSTRACT FROM AUTHOR]

Hypoxia‐associated radioresistance in rectal cancer (RC) has severely hampered the response to radioimmunotherapy (iRT), necessitating innovative strategies to enhance RC radiosensitivity and improve iRT efficacy. Here, a catalytic radiosensitizer, DMPtNPS, and a STING agonist, cGAMP, are integrated to overcome RC radioresistance and enhance iRT. DMPtNPS promotes efficient X‐ray energy transfer to generate reactive oxygen species, while alleviating hypoxia within tumors, thereby increasing radiosensitivity. Mechanistically, the transcriptomic and immunoassay analysis reveal that the combination of DMPtNPS and RT provokes bidirectional regulatory effects on the immune response, which may potentially reduce the antitumor efficacy. To mitigate this, cGAMP is loaded into DMPtNPS to reverse the negative impact of DMPtNPS and RT on the tumor immune microenvironment (TiME) through the type I interferon‐dependent pathway, which promotes cancer immunotherapy. In a bilateral tumor model, the combination treatment of RT, DMPtNPS@cGAMP, and αPD‐1 demonstrates a durable complete response at the primary site and enhanced abscopal effect at the distant site. This study highlights the critical role of incorporating catalytic radiosensitizers and STING agonists into the iRT approach for RC. [ABSTRACT FROM AUTHOR]

X‐rays are rays that penetrate the human tissue and are capable of penetrating water, air, and oxygen in various biological tissues or tumors. In recent years, significant progress has been made in the research of X‐ray‐excited luminescent materials for cancer diagnosis and treatment. In this study, the application of X‐ray‐excited luminescent materials is reviewed for tumor imaging and therapy. First, two classes of luminescent materials are briefly introduced for a form of enhanced X‐ray computed tomography, X‐ray‐excited optical luminescence imaging. Subsequently, the design of multifunctional hybrid materials is evaluated for radiotherapy and other treatments and their synergistic effects under X‐ray excitation are studied. Finally, current key issues and solutions in the field are discussed in detail. [ABSTRACT FROM AUTHOR]

Lanthanides have unique electronic configurations and stepped energy states of [Xe]4fN, which endows them with advantages including stable luminescence, large stokes shift, wide excitation spectral bands, and long fluorescence lifetime. NIR‐II fluorescence imaging overcomes the strong tissue absorption, scattering, and spontaneous fluorescence interference of traditional fluorescence and can achieve deeper tissue penetration and higher spatial and temporal resolution in vivo imaging. Lanthanides hold great potential for in vivo biosensing and bioimaging. In this work, the design and preparation of nanomaterials doped with different lanthanide elements are reviewed in this paper. Applications of lanthanide‐doped nanomaterials to different tumor therapeutics through NIR‐II fluorescence imaging and the unique potential of NIR lanthanide nanomaterials in tumor diagnosis and therapy are also discussed. [ABSTRACT FROM AUTHOR]

Bacterial infection becomes a severe threat to human life and health worldwide. Antibiotics with the ability to resist pathogenic bacteria are therefore widely used, but the misuse or abuse of antibiotics can generate multidrug‐resistant bacteria or resistant biofilms. Advanced antibacterial technologies are needed to counter the rapid emergence of drug‐resistant bacteria. With the excellent optical properties, engineerable surface chemistry, neglectable biotoxicity, gold nanocrystals are particularly attractive in biomedicine for cancer therapy and antibacterial therapy, as well as nanoprobes for bioimaging and disease diagnosis. In this perspective, gold nanocrystal‐based antibacterial performance and deep‐tissue imaging are summarized, including near‐infrared‐light excited photoacoustic imaging and fluorescence imaging through deep tissue infections. On the basis of integrating "imaging‐therapy‐targeting" in single nanotheranostic, the current challenges of imaging‐guided antibacterial and therapy based on gold nanocrystals are discussed, and some insights are provided into the gold nanocrystal‐based nanoplatform that integrates antibacterial activity and therapy. This perspective is expected to provide comprehensive guidance for diagnosing and combating bacterial infections based on gold nanostructures. [ABSTRACT FROM AUTHOR]

Black phosphorus is a two‐dimensional layer material with promising applications due to its many excellent physicochemical properties, including high carrier mobility, ambipolar field effect and unusual in‐plane anisotropy. Currently, BP has been widely used in biomedical engineering, photocatalysis, semiconductor devices, and energy storage electrode materials. However, the unique structure of BP makes it highly chemically active, leading to its easy oxidation and degradation in air, which limits its practical applications. Recently, researchers have proposed a number of initiatives that can address the environmental instability of BP, and the application of these physical and chemical passivation techniques can effectively enhance the environmental stability of BP, including four modification methods: covalent functionalization, non‐covalent functionalization, surface coordination, physical encapsulation and edge passivation. This review highlights the mechanisms of the above modification techniques in addressing the severe instability of BP in different application scenarios, as well as the advantages and disadvantages of each method. This review can provide guidance for more researchers in studying the marvellous properties of BP and accelerate the practical application of BP in different fields. [ABSTRACT FROM AUTHOR]

The injectable hydrogels can deliver the loads directly to the predetermined sites and form reservoirs to increase the enrichment and retention of the loads in the target areas. The preparation and injection of injectable hydrogels involve the sol–gel transformation of hydrogels, which is affected by factors such as temperature, ions, enzymes, light, mechanics (self‐healing property), and pH. However, tracing the injection, degradation, and drug release from hydrogels based on different ways of gelation is a major concern. To solve this problem, contrast agents are introduced into injectable hydrogels, enabling the hydrogels to be imaged under techniques such as fluorescence imaging, photoacoustic imaging, magnetic resonance imaging, and radionuclide imaging. This review details methods for causing the gelation of imageable hydrogels; discusses the application of injectable hydrogels containing contrast agents in various imaging techniques, and finally explores the potential and challenges of imageable hydrogels based on different modes of gelation. [ABSTRACT FROM AUTHOR]

The development of theragnostic nanosystems integrating FRET (fluorescence resonance energy transfer) imaging and chemodynamic therapy (CDT) for accurate diagnosis and effective treatment of lung tumors is still a big challenge. Herein, a peptide-assembled 3D DNAzyme motor nanodevice is engineered for a self-powered FRET amplifier profiling human neutrophil elastase (HNE) and self-supplied H 2 O 2 enhancing CDT. The nanodevice is prepared by depositing AuNPs on ZIF-8, in which ZIF-8 co-loaded the lysosomal targeting peptide-modified copper peroxides (PCPs) and hairpins (H1, H2, and H3), AuNPs are co-labeled by DNAzyme-peptide (DP) conjugate and H3. In the tumor micro-environment, HNE driven 3D DNAzyme walker followed by an exponential amplification constructed by a synergistic cross-activation between hybridization chain reaction and DNAzyme, generating a self-powered FRET amplifier. The FRET amplifier specifically measures HNE with a sensitivity of 0.026 pM, and successfully images exogenous HNE in living cells and monitors HNE in mouse models. Moreover, the PCPs can target lysosomes, reducing lysosome escape. The self-supplying H 2 O 2 undertaken by PCPs improves the Cu (II)-catalyzed Fenton-like reaction, effectively causing cell apoptosis to inhibit tumor growth. Significantly, the nanodevice successfully screens inhibitors and discriminates the HNE level in normal and lung cancer tissues, suggesting that the nanodevice provides an effective tool for the diagnosis and treatment of lung tumors., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

The abnormal fluctuation of temperature in vivo usually reflects the progression of inflammatory diseases. Noninvasive, real-time, and accurate monitoring and imaging of temperature variation in vivo is advantageous for guiding the early diagnosis and treatment of disease, but it remains difficult to achieve. Herein, we developed a temperature-activated near-infrared-II fluorescence (NIR-II FL) and surface-enhanced Raman scattering (SERS) nanoprobe for long-term monitoring of temperature changes in rat arthritis and timely assessment of the status of osteoarthritis. The thermosensitive polymer bearing NIR-II FL dye was grafted onto the surface of nanoporous core-satellite gold nanostructures to form the nanoprobe, wherein the nanoprobe contains NIR-II FL and Raman reference signals that are independent of temperature change. The ratiometric FL 1150/ FL 1550 and S 1528 /S 2226 values of the nanoprobe exhibited a reversible conversion with temperature changes. The nanoprobe accurately distinguishes the temperature variations in the inflamed joint versus the normal joint in vivo by ratiometric FL and SERS imaging, allowing for an accurate diagnosis of inflammation. Meanwhile, it can continuously monitor fluctuations in temperature over an extended period during the onset and treatment of inflammation. The tested temperature change trend could be used as an indicator for early diagnosis of inflammation and real-time evaluation of therapeutic effects., (© 2024 Wiley-VCH GmbH.)

The enhancement of detection sensitivity in microfluidic sensors has been a continuously explored field. Initially, many strategies for sensitivity improvement involved introducing enzyme cascade reactions, but enzyme-based reactions posed challenges in terms of cost, stability, and storage. Therefore, there is an urgent need to explore enzyme-free cascade amplification methods, which are crucial for expanding the application range and improving detection stability. Metal or metal compound nanomaterials have gained great attention in the exploitation of microfluidic sensors due to their ease of preparation, storage, and lower cost. The unique physical properties of metallic nanomaterials, including surface plasmon resonance, surface-enhanced Raman scattering, metal-enhanced fluorescence, and surface-enhanced infrared absorption, contribute significantly to enhancing detection capabilities. The metal-based catalytic nanomaterials, exemplified by Fe 3 O 4 nanoparticles and metal-organic frameworks, are considered viable alternatives to biological enzymes due to their excellent performance. Herein, we provide a detailed overview of the applications of metals and metal compounds in improving the sensitivity of microfluidic biosensors. This review not only highlights the current developments but also critically analyzes the challenges encountered in this field. Furthermore, it outlines potential directions for future research, contributing to the ongoing development of microfluidic biosensors with improved detection sensitivity., (© 2024 Wiley-VCH GmbH.)