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Antibiotics abuse has caused various problems threatening human health and ecological environment. Monitoring antibiotics residual levels is of great significance, yet still challenging for quantitative point-of-need testing with high-sensitivity and visual capability. Here we developed a competitive lateral flow immunoassay (CLFIA) platform with flexible readout for enrofloxacin (ENR), a regularly added antibiotic. To overcome the limitation of low sensitivity of traditional colloidal gold-based CLFIA, the three-dimensionally assembled gold nanoparticles (AuNPs) within dendritic silica scaffold were fabricated as signal reporters. The assembly structure effectively retained the intrinsic absorption features of hydrophobic AuNPs and greatly enhanced the light extinction ability of a single label for signal amplification. The obtained CLFIA strips can not only achieve qualitative screening of ENR at a very low concentration by naked eye (cutoff value: 0.125 ng/mL), but also enable ultrasensitive quantification of ENR by an optical scanner (limit of detection: 0.00195 ng/mL) or a smartphone (limit of detection: 0.0078 ng/mL). Moreover, to elaborate the visual inspection degree of CLFIA against traditional yes/no interpretation, a novel multirange gradient CLFIA strip was prepared for visually semiquantitative identification of ENR with four concentration ranges. The novel CLFIA platform demonstrated sensitive, specific, and reliable determination of ENR with flexible signal readout and provides a potential and invigorating pathway to point-of-need immunoassay of antibiotics.

Despite the growing interest, limited studies have been conducted on LID spatial allocation optimization (SAO) at neighborhood scale, and no study has applied modifications to the optimization algorithm to improve its performance. In this study, such a new LID SAO system was proposed, which integrated a hydrological computing engine (SWMM) with an optimization algorithm (PICEA-g) using a programming language (MATLAB) as the platform. The specific modifications to the PICEA-g algorithm include: new methodologies for initializing candidate solutions, defining goal vector boundaries and enhanced genetic operators. The new LID SAO system was tested in a typical urban residential neighborhood in western Canada, and optimal solutions for LID implementation (bioretention, rain garden, permeable pavement and green roof) were obtained. The results showed that promising hydrologic benefits of reducing peak flow rate and total volume of stormwater runoff from the catchment, can be achieved with a relatively low cost. The LID SAO system provides users with flexibility and feasibility for a variety of drainage locations, scales and objectives (e.g., water quality).

The single-crystal-to-single-crystal (SCSC) transformations of metal-organic frameworks (MOFs) are fascinating because we can directly observe the change of the crystal structure during the transformation process. It also greatly helps to understand the delicate interaction between the guest molecules and the skeleton framework and therefore fosters a deep understanding of gas storage and separation within the frameworks. Herein, we report two novel MOFs, [Cu

The first alkaline earth metal borate-nitrate, namely Ba

The exploration of A-Mo-P-O (A = Rb, Cs) systems has allowed several new Mo(V) phosphates, Rb

Five new α-pyrones, xylariaopyrones E–I (1–5), along with three known analogues (6–8) were isolated from the cultivation broth of the endophytic fungus Xylariales sp. (HM-1). The structures of the ...

Herein, a one-step electrochemical sensor for selective and sensitive detection of lead ion Pb2+ was developed based on an integrated probe meso-tetra(4-carboxyphenyl) porphine (TCPP)-multi-walled carbon nanotubes (MWCNTs)@Fe3O4, which is TCPP-modified magnetic multi-walled carbon nanotubes. In the integrated probe, TCPP is a porphyrin with a specific cavity structure which could selectively chelate with Pb2+, MWCNTs with good electric conductivity provide a place to load TCPP and form a specific adsorption state of Pb2+ on the electrode surface, and Fe3O4 enables the rapid separation and one-step fabrication of the electrochemical sensor. Based on it, the sample pre-enrichment, separation and determination can be integrated, making the whole process very fast and simple. In addition, fast scan voltammetry (FSV) with a scan rate up to 200 V/s could be used to improve the detection sensitivity greatly, benefitting from the specific adsorption state formed. Under the optimal conditions obtained through orthogonal experiments including adsorption time, integrated probe dosage and solution pH, there was a good linear relationship between the peak current and Pb2+ concentration ranging from 2.0 × 10−4 μg L−1 to 2.0 × 10−3 μg L−1, with the limit of detection (LOD) being 6.7 × 10−5 μg L−1 (S/N = 3) i.e. 0.067 ppt. Analysis of actual water samples was successful. Therefore, being simple, fast, selective and sensitive, the one-step electrochemical sensor proposed has a good potential in practical applications.

A new method was constructed for detecting dopamine based on aptamer-specific recognition and resonance Rayleigh scattering (RRS) of G - quadruplex nanowires (G - wires). The dopamine aptamer was used to recognize the target of dopamine, and the Exonuclease III was applied to cleave the hairpin DNA, and the G - wire formation was induced in the presence of K+ and Mg2+. This phenomenon was confirmed by polyacrylamide gel electrophoresis. Thus, a quantitative relationship between the RRS intensity of the G - wires and the dopamine concentration was established. The experimental conditions were optimized, such as the concentration of Mg2+, reaction temperature, reaction time and the concentration of Exonuclease III in the reaction system, and the interference substances were investigated, such as uric acid, ascorbic acid and serotonin. Under the optimal conditions, there was a good linear relationship between the RRS and the logarithm of dopamine concentration in the range from 5.0 × 10-11 M to 1.0 × 10-8 M (r = 0.995), with a detection limit of 1.2 × 10-11 M. The novel method for dopamine detection showed excellent selectivity and high sensitivity, and could be used to detect dopamine in mice brain tissues.

A major impediment of the incorporation of extra functional groups on skeletons of covalent organic frameworks (COFs) is the long-ordered microporosity over their networks. This problem has delayed the practical applications of these highly porous materials for chemical sensing, CO2 capture, and heterogeneous catalysis. In this work, we demonstrated a facile method named the nonstoichiometric synthon strategy to introduce functional groups onto the network of the COFs for further metallic nanoparticle confinement. By simply adjusting the ratio of primitive synthons, we can deliberately decorate the interior pores of the resultant COF materials with amine groups from the excess synthon fragments, while maintaining the structure of the parent COF. Benefiting from the excess dangling amine groups on the network, these COFs are readily available as catalytic support for the confinement of ultrasmall metallic Pd nanoclusters and further used for the benzyl alcohol oxidation reaction.

A pair of new phenolic bisabolane-type sesquiterpenoid enantiomers (±)- phomoterpenes A and B [(±)-1] and two known analogues (2 and 3), together with two new isocoumarins, phomoisocoumarins C‒D (4‒5), were isolated from an endophytic fungus Phomopsis prunorum (F4-3). Their structures were elucidated by comprehensive spectroscopic analysis. The enantiomeric separation for (±)-1 were achieved by chiral-HPLC, and their absolute configurations were assigned by electronic circular dichroism (ECD) calculation. Compounds (+)-1 and 5 exhibited moderate antibacterial activity against plant pathogenic bacteria Pseudomonas syringae pv. Lachrymans with MIC values of 15.6 μg/mL.

Flexible strain sensors, based on their good electrical conductivity and strain sensitivity, are widely used in wearable health monitoring, sensitive tactile information display and multi-functional robot skin. However, it is still a challenge for wearable devices to prepare conductive hydrogel with flexibility, high strain, high sensitivity and biocompatibility. Herein, we designed an interpenetrating network conductive composite hydrogel, which composed with polyaniline, double bond modified chitosan and acrylamide, has excellent strength and toughness due to its unique physically and chemically cross-linked double network. The obtained hydrogel exhibited good tensile strength (0.3 MPa), high electrical conductivity (6.97 S/m) and strain sensitivity (gauge factor 15.9). The results showed that the strain sensor could detect the movement of human joints through electrical signals, and had good stability and reproducibility, which indicated that it was expected to be used in wearable health monitoring and multi-functional robot skin.

Here we present the design and synthesis of a new robust microporous organic polymer (TPBP) decorated with phenazine groups which endowed reversibly redox-active properties. The obtained TPBP possesses relatively high surface area (359 m2/g) and good thermal stability. TPBP exhibits excellent catalytic capability for the oxidative homocoupling of amines with high activity and selectivity toward target products. Besides, this metal-free catalyst demonstrated excellent recyclability after 6 cycles under the investigated conditions. By means of EPR and UV-vis spectroscopy, a plausible mechanism of the amine oxidative coupling reaction was deduced via a single electron transfer from TPBP radical cations to amine substrates.

Acetaminophen (APAP) overdose can lead to acute, severe kidney injury, which has recently attracted considerable attention among researchers and clinicians. Unfortunately, there are no well-established treatments for APAP-induced renal injury, and the molecular mechanism of APAP-induced kidney injury is still unclear. Herein, we explored the protective effects of interleukin (IL)-22 on APAP-induced renal injury and the underlying molecular basis. We found that IL-22 could significantly alleviate the accumulation of reactive oxygen species (ROS) and ameliorate mitochondrial dysfunction, reducing APAP-induced renal tubular epithelial cell (TEC) death in vitro and in vivo. Furthermore, IL-22 could downregulate the APAP-induced NLRP3 inflammasome activation and mature IL-1β release in kidney injury. Additionally, the APAP-mediated upregulation of the serum levels of IL-18, TNF-α, IL-6, and IL-1β was obviously decreased, suggesting IL-22 has inhibitory effects on inflammatory responses. Conclusively, our study demonstrated that IL-22 exerted ameliorative effects on APAP-induced kidney injury by alleviating mitochondrial dysfunction and NLRP3 inflammasome activation, suggesting that IL-22 represents a potential therapeutic approach to treat APAP-induced kidney injury. KEY POINTS: • IL-22 could ameliorate APAP that triggered oxidative stress and mitochondrial dysfunction. • IL-22 could reduce APAP that caused inflammatory responses. Graphical abstract.

This study compared Sheng Xue Ning (SXN) tablets with ferrous succinate (FS) tablets in terms of their efficacy for the treatment of iron-deficient renal anemia and safety in patients subject to maintenance hemodialysis (MHD). A total of 94 patients undergoing MHD were randomly assigned to an experiment group (receiving oral SXN tablets, SXN group) and a control group (orally given FS tablets, FS group) and followed up for 12 weeks. Erythropoietin (EPO) was used in both groups. The efficacy was assessed by detecting the subsequent changes in hemoglobin (Hb), serum iron (SI), SF and transferrin saturation (TSAT). At the 12th week, Hb and TSAT levels in both groups were significantly increased compared to those in the screening period (P

The self-assembled gold nanoparticle (NP) superlattice displays unusual but distinctive features such as high mechanical and free-standing performance, electrical conductivity, and plasmonic properties, which are widely employed in various applications especially in biological diagnostics and optoelectronic devices. For a two-dimensional (2D) superlattice monolayer film composed of a given metal nanostructure, it is rather challenging to tune either its plasmonic properties or its optical properties in a reversible way, and it has not been reported. It is therefore of significant value to construct a free-standing 2D superlattice monolayer film of gold nanoparticles with an intelligent response and desired functions. Herein, we developed an easy and efficient approach to construct a gold nanoparticle superlattice film with a dual-responsive plasmonic switch. In this system, gold nanoparticles were coated by polyaniline (PANI) and then interracially self-assembled into a monolayer film at the air-liquid interface. The PANI shell plays two important roles in the superlattice monolayer film. First, the PANI shell acts as a physical spacer to provide a steric hindrance to counteract the van der Waals (vdW) attraction between densely packed nanoparticles (NPs), resulting in the formation of a superlattice by adjusting the thickness of the PANI shell. Second, the PANI shells provide the superlattice film with multiple stimuli such as electrical potential and pH change, leading to reversible optical and plasmonic responsiveness. The superlattice monolayer film can show a vivid color change from olive green to pink, or from olive green to violet by the change of the corresponding stimuli. Also, the localized surface plasmonic resonance (LSPR) of the superlattice monolayer film can be reversibly modulated by both by changing the local pH and applying an electric potential. Notably, a significant plasmonic shift of 157 nm can be achieved in the superlattice monolayer film when the PANI shell with a thickness of 35 nm and gold nanorods as a core were used. The superlattice monolayer film with dual-responsive plasmonic switches is promising for a range of potential applications in optoelectronic devices, plasmonic and colorimetric sensors, and surface-enhanced Raman scattering (SERS).

Context Nephrolithiasis is a major public health problem worldwide and Fu-Fang-Jin-Qian-Cao granules (FFJQC) is a traditional Chinese herbal formula that is used to treat nephrolithiasis. The main component of nephrolithiasis is calcium oxalate (CaOx) and the epithelial-mesenchymal transition (EMT) shown to play a crucial role in CaOx-induced kidney injury. However, the mechanism underlying the therapeutic effect of FFJQC on the CaOx-induced renal EMT is unknown. Objective This study explores the therapeutic benefits and mechanism of FFJQC in oxalate-induced kidney injury. Materials and methods 60 male C57BL/6 mice were used in this experiment and divided into 6 groups. A mouse kidney stone model was created by intraperitoneal injection of glyoxylate at a dose of 100 mg/kg for 6 days. The standardized FFJQC was used to treat mouse crystal kidney injury by gavage at 1.35 and 2.7 g/kg, respectively. Western blotting and immunostaining for E-cadherin, cytokeratin 18 (CK18), vimentin, smooth muscle α-actin (α-SMA) and transforming growth factor β (TGF-β)/Smad pathway were conducted on renal tissues. Results Following CaOx-induced kidney injury, the levels of E-cadherin and CK18 in kidney decreased, while vimentin and α-SMA levels increased. The FFJQC treatment increased the levels of E-cadherin and CK18 and decreased vimentin and α-SMA levels in varying degrees. What’s more, the FFJQC reduced the expression of CaOx-induced fibrosis marker collagen II. Conclusion FFJQC alleviated the CaOx-induced renal EMT and fibrosis by regulating TGF-β/smad pathway. Therefore, the FFJQC is an important traditional Chinese medicine for the treatment of CaOx-induced renal injury and fibrosis.

Without using any additives, a practical and eco-friendly methodology has been realized for the tandem double cyclization of 1,6-dienes with easily accessible azobis(alkylcarbonitriles) on water. This chemistry has mild reaction conditions, employing water as the sole solvent, with high regioselectivity and ease of scale-up. Moreover, this is the first example of 1,n-diene cyclization using azobis(alkylcarbonitriles) as a two-carbon unit for the construction of polycyclic skeletons.

In this work, we designed a simple and intelligent method to detect cyromazine. After original citrate stabilized AuNPs were modified with Tween 20, they could remain stable under complex conditions of different pH values (5.5–8.0) and high ionic strength. However, after the addition of cyromazine, ligand exchange occurred with the citrate ion on the surface of Tween 20–AuNPs, resulting in instability and aggregation of Tween 20–AuNPs. At the same time, a new absorption peak appeared near 630 nm, and the color changed from red to blue. This method has been successfully applied to the detection of cyromazine in milk and cucumber. Furthermore, this method was used in conjunction with a smartphone to intelligently detect and analyze cyromazine at concentrations as low as 0.04 mg kg−1.

Aggregation-induced emission (AIE) properties have been widely investigated not only because they thoroughly circumvent the notorious aggregation-caused quenching effect encountered in conventional fluorophores but also due to their promising applications in organic light-emitting diodes, fluorescent sensors and bioimaging. In this work, we reported a study of the molecular packing and luminescence properties of AIE active positional isomers (m-BPCDM and p-BPCDM) with carbazole and dicyanovinyl groups. The compound m-BPCDM based on meta-substitution showed more evident AIE processes than the compound p-BPCDM based on para-substitution, which can be attributed to the strong π–π stacking effect brought by the spatial structure of p-BPCDM. Moreover, the two positional isomers also exhibited distinct mechanochromic luminescence properties.

When a pig mounted with permanent magnets gets stuck in the pipeline, it can be located by detecting the magnetic anomalies on the ground using a single-axis magnetic sensor. In order to collect the magnetic anomaly efficiently through single-axis magnetic sensor, a geometric detection model and calculation method for single-axis magnetic anomaly detection is established in this paper. The distribution of magnetic inclination and declination of the measuring points is obtained. The results indicate that the magnetic inclination of all measuring points vary within a small range of 2°, and this value is highly dependent on the magnetic sensor which is configured aboveground around the geomagnetic inclination. However, the magnetic declination at different points of detection surface is subject to the geomagnetic components and the Y-axis component of the magnetic field of magnets. The magnetic declinations distribute irregularly and vary in a wide range. Therefore, to achieve a high-efficiency detection with the single-axis sensor, the sensor shall be placed in such a manner that the magnetic inclination thereof coincides with the geomagnetic inclination. The magnetic declination of the sensor can be calculated using s, the superposed Y-axis component induced by the permanent magnets, and the corresponding formula given in this paper. The article demonstrates the feasibility of locating a blocked pig in the pipeline based on the single-axis magnetic anomaly detection. It will have a practical significance in guiding the engineering detection. Keywords: Pig blockage, Pig locating, Single-axis magnetic anomaly, Magnetic anomaly detection, Optimized installation of sensor

Four new furostanol saponins, named aspidsaponins E-H (1–4) were isolated from the rhizomes of Aspidistra elatior Blume. Their structures were determined based on chemical methods and spectral data. Compounds 1 and 2 were a pair of diastereoisomeric furostanol saponins and possessed the highly oxidized structural feature of 1β, 2β, 3β, 4β, 5β, 26-hexanol-steroids, and compounds 3-4 were steroidal glycosides with a tetra-saccharide chain at C3. The isolated compounds (1–4) were tested in vitro for inhibitory activities against LPS-induced nitric oxide production in RAW264.7 macrophages. Among them, compounds 3 and 4 showed excellent anti-inflammatory activities with IC50 values 82.1 and 65.9 μM, respectively.

A water-stable and pH-independent sensor for qualitative and quantitative detection of nicotine in urine solution and living cell was successfully developed. This material, named MB@UiO-66-NH2, can be synthesized by encapsulating methylene blue (MB) with a well-known metal-organic framework (MOF) UiO-66-NH2 through a simple impregnation method. The fluorescence intensity of the system was significantly enhanced when a certain amount of nicotine was added. In the meanwhile, MB is reduced by reductive nicotine to form leucomethylene blue (LB). The proposed sensor displayed excellent selectivity and sensitivity toward nicotine with limit of detection (LOD) of 0.98 μM, which is comparable or even better than that of the electrochemistry detecting methods for nicotine. The obvious enhancement and blue shift of the emission arise from the photoinduced electron transfer (PET) from LB to the UiO-66-NH2. The photophysical properties and the sensing applications of MB@UiO-66-NH2 suggest that this composite can be acted as a sensitive, selective, recyclable, and fluorogenic sensor for nicotine determination in urine solution and living cell.

Electrochemiluminescence immunoassays are usually carried out through "on-electrode" strategy, i.e., sandwich-type immunoassay format, the sensitivity of which is restricted by two key bottlenecks: (1) the number of signal labels is limited and (2) only a part of signal labels could participate in the electrode reaction. In this Perspective, we discuss the development of an "in-electrode" Faraday-cage-type concept-based immunocomplex immobilization strategy. The biggest difference from the traditional sandwich-type one is that the designed "in-electrode" Faraday-cage-type immunoassay uses a conductive two-dimensional (2-D) nanomaterial simultaneously coated with signal labels and a recognition component as the detection unit, which could directly overlap on the electrode surface. In such a case, electrons could flow freely from the electrode to the detection unit, the outer Helmholtz plane (OHP) of the electrode is extended, and thousands of signal labels coated on the 2-D nanomaterial are all electrochemically "effective." Thus, then, the above-mentioned bottlenecks obstructing the improvement of the sensitivity in sandwich-type immunoassay are eliminated, and as a result a much higher sensitivity of the Faraday-cage-type immunoassay can be obtained. And, the applications of the proposed versatile "in-electrode" Faraday-cage-type immunoassay have been explored in the detection of target polypeptide, protein, pathogen, and microRNA, with the detection sensitivity improved tens to hundreds of times. Finally, the outlook and challenges in the field are summarized. The rise of Faraday-cage-type electrochemiluminescence immunoassay (FCT-ECLIA)-based biosensing strategies opens new horizons for a wide range of early clinical identification and diagnostic applications.

Long noncoding RNA (lncRNA) has been suggested to play an important role in a variety of diseases over the past decade. In a previous study, we identified a novel lncRNA, termed HOXA11‐AS, which was significantly up‐regulated in calcium oxalate (CaOx) nephrolithiasis. However, the biological function of HOXA11‐AS in CaOx nephrolithiasis remains poorly defined. Here, we demonstrated that HOXA11‐AS was significantly up‐regulated in CaOx nephrolithiasis both in vivo and in vitro. Gain‐/loss‐of‐function studies revealed that HOXA11‐AS inhibited proliferation, promoted apoptosis and aggravated cellular damage in HK‐2 cells exposed to calcium oxalate monohydrate (COM). Further investigations showed that HOXA11‐AS regulated monocyte chemotactic protein 1 (MCP‐1) expression in HK‐2 cell model of CaOx nephrolithiasis. In addition, online bioinformatics analysis and dual‐luciferase reporter assay results showed that miR‐124‐3p directly bound to HOXA11‐AS and the 3'UTR of MCP‐1. Furthermore, rescue experiment results revealed that HOXA11‐AS functioned as a competing endogenous RNA to regulate MCP‐1 expression through sponging miR‐124‐3p and that overexpression of miR‐124‐3p restored the inhibitory effect of proliferation, promotion effects of apoptosis and cell damage induced by HOXA11‐AS overexpression. Taken together, HOXA11‐AS mediated CaOx crystal–induced renal inflammation via the miR‐124‐3p/MCP‐1 axis, and this outcome may provide a good potential therapeutic target for nephrolithiasis.

Sorption to biofilms is thought to be a crucial process controlling the fate of trace organic contaminants in aquatic systems. The organic composition of biofilms is regarded as the determining factor in the sorption mechanism of biofilm organic carbon fractions; however, its role is not well known. Here, the sorption of phenanthrene and ofloxacin was modeled with classic and emerging organic contaminants, respectively, by comparatively investigating nine type of freshwater biofilms cultured in a river, lake, and reservoir in spring, summer, and autumn. The chemical features of the nine biofilms were analyzed using elemental analysis, infrared spectroscopy, X-ray photoelectron spectroscopy, and carbon-13 nuclear magnetic resonance. Results showed that the freshwater biofilms were aliphatic-rich natural amorphous solid substances with O-containing functional groups, and their surface polarity was significantly lower than their bulk polarity. All the isotherms of phenanthrene and ofloxacin sorption by the biofilms were linear. The organic carbon-normalized partition coefficient values for phenanthrene and ofloxacin on the nine biofilms ranged from 91.9 to 364.2 L g−1 and 3.2 to 43.2 L g−1, respectively. The van der Waals interaction between a majority of aliphatic carbon (73.4%–83.9%) in biofilms and the two sorbates was much stronger than π-π interactions between a minority of aromatic carbon (12.7%–21.7%) and sorbates. The surface polarity of the biofilms regulated polar interactions including the hydrogen bonding and electron donor–acceptor interactions. Both the aliphatic carbon and surface polarity in the biofilms enhanced the sorption of phenanthrene and ofloxacin. The sorption characteristics and mechanisms of polycyclic aromatic hydrocarbons and antibiotics on biofilms shown in our present and previous studies are different from those of other ubiquitous natural solid materials such as soils and sediments. This study provides insight into the importance of aliphatic carbon fractions of freshwater biofilms for the sorption of classic and emerging organic contaminants.

A new alkali-metal iodate, K

4,6-α-Glucanotransferases (4,6-α-GTs) hold great potential for applications in the food and medical industries because of their efficient transglycosylation ability. However, it is relatively difficult to achieve high soluble expression because of their high molecular weight and multidomain nature. In this study, 4,6-α-GT of Burkholderia sp. (GtfR2) was successfully expressed in E. coli, and the activity attained 1.55 × 10

The sorption of antibiotics on iron (hydr)oxides is an important process that influences their environmental fate. Ferrihydrite (Fh) nanosized iron hydroxide is omnipresent in nature. However, the sorption mechanism of fluoroquinolone (FQ) antibiotics on Fh is unclear. Here, a combined experimental and computational study was conducted to investigate the sorption of enoxacin (ENO) as one model of FQs on Fh. Pipemidic acid (PPA), as a structural analog of ENO, was selected to compare the effect of fluorinated substituent on the sorption mechanism. Results indicated that the average K

Two new sodium aluminum borates, Na 3 AlB 8 O 15 and Na 3 Al 2 B 7 O 15 , have been successfully synthesized by the high-temperature solution method. They crystallize in the different space groups, P 2 1 / c and P 2/ c , respectively. The B-O configurations of β-Na 2 B 6 O 10 , Na 3 AlB 8 O 15 and Na 3 Al 2 B 7 O 15 are compared to feature complicated different dimensional open-framework structures caused by the substitution of [BO 4 ] by [AlO 4 ] covalent tetrahedra. Moreover, the experimental results indicate that Na 3 AlB 8 O 15 and Na 3 Al 2 B 7 O 15 have short ultraviolet (UV) cutoff edges (

Antibiotics are increasingly detected in fish caught in ice-free waters, but information on fish caught in ice-sealed waters is insufficient. The concentrations of 23 antibiotics in the gills, muscles, kidneys, livers, biles, and brains of Cyprinus carpio and Hypophthalmichthys nobilis caught during winter fish-hunting activities in Chagan Lake, Haernao Reservoir, and Shitoukoumen Reservoir were systematically studied to ascertain the variations among fish species and fishing regions, tissue distribution, and bioaccumulation, as well as the potential risk to humans via the consumption of contaminated fish. The results indicated that the individual antibiotic concentration in tissues ranged from undetectable to 35.0 ng/g ww. The total antibiotic concentration in fish muscles from Shitoukoumen Reservoir was lower than that from Chagan Lake and Haernao Reservoir, but showed no significant difference between Cyprinus carpio and Hypophthalmichthys nobilis. Chloramphenicols had a high proportion in most fish tissues ranging from 28.3% to 44.0%, and the antibiotics were mainly distributed in the livers with a total concentration of 54.8 ± 9.9 ng/g ww. The mean values of bioaccumulation factors (BAF) of antibiotics in tissues ranged from 79.4 to 1000 L/kg, with the higher values found in the fish livers. The hazard quotient and hazard index value of antibiotics in the muscles of fish from ice-sealed were less than 1, indicating a negligible risk to human health via the consumption of fish muscles. This study revealed that the total antibiotic concentration in muscles showed spatial variations but not fish species-dependence. The antibiotics mainly accumulated in the livers. In addition, the target antibiotic concentrations in the muscles of fish from ice-sealed waters met the safe for consumption criteria.

Two new sodium aluminum borates, Na

Using the ionic salt characteristics of CsPbBr3 perovskite nanocrystals (CsPbBr3 NCs), the fluorescence wavelength of CsPbBr3−xIx NCs could be changed by the halogen exchange reaction between CsPbBr3 NCs and oleylammonium iodide (OLAM-I). Under the excitation of a 365 nm UV lamp and the increase of OLAM-I concentration, the content of iodine in CsPbBr3−xIx NCs increased, and the fluorescence emission wavelength showed a redshift from 511.6 nm to 593.4 nm, resulting in the fluorescence color change of CsPbBr3 NCs from green to orange-red. Since OLAM-I is a mild reducing agent and easily oxidized by benzoyl peroxide (BPO), a novel colorimetric sensing approach for BPO based on the fluorescence wavelength shift was established in this study. The linear relationship between the different wavelength shifts (Δλ) and the concentration of BPO (CBPO) is found to be in the range of 0 to 120 μmol L−1. The coefficient of alteration (R2) and the detection limit are 0.9933 and 0.13 μmol L−1 BPO, respectively. With this approach, the determination procedure of BPO in flour and noodle samples can be achieved in only a few minutes and exhibit high sensitivity and selectivity.

In this paper, based on the fluorescence of carbon quantum dots (CQDs) quenched by mercury ions (Hg

Formaldehyde is a very representative indoor organic pollutant, which can exist in indoor spaces for a long time. Using purified formaldehyde dehydrogenase can improve the efficiency of formaldehyde degradation. Comparing the enzyme activities of externally purified formaldehyde dehydrogenase at different temperatures and pH values, a simple, rapid, and rough evaluation method for verifying the removal of formaldehyde by the formaldehyde dehydrogenase was preliminarily established.