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This study investigated whether rs1784692 is a risk factor for polycystic ovary syndrome (PCOS) in Han Chinese women. A case-control study was conducted in Han Chinese women, involving 526 PCOS patients and 522 control participants. A TaqMan MGB probe assay was used to genotype the variant rs1784692. Dominant and additive models were employed for genotype–phenotype association analysis in the PCOS and control samples. The minor allele C of rs1784692 is protective against PCOS (odds ratio [OR] 0.556, 95% confidence interval [CI] 0.408–0.759, P = 1.83 × 10–4), even after adjustment for body mass index (BMI) and age (OR adj 0.539, 95% CI 0.391–0.743, P adj = 1.62 × 10–4). Genotype–phenotype analysis of the dominant model showed that mean BMI in the CC+CT group was higher than in the TT group in the PCOS group (27.12 ± 5.82 versus 24.57 ± 4.52, P = 1.0 × 10–3), but not in the control groups, indicating that the minor allele C of rs1784692 associates with BMI in women with PCOS. The mean LH (luteinizing hormone) concentration in the CC+CT group was lower than in the TT group in PCOS and control participants (9.33 ± 5.08 versus 10.93 ± 5.91, P = 0.036; 4.39 ± 1.66 versus 4.89 ± 2.07, P = 0.021). Genotype–phenotype analysis of additive model showed that mean BMI in TC group was higher than in the TT group in PCOS patients compared with control participants (27.14 ± 5.81 versus 24.57 ± 4.52, P = 3.06 × 10–3). The SNP rs1784692 in gene ZBTB16 is protective against PCOS but is associated with increased BMI in Han Chinese women with PCOS. [ABSTRACT FROM AUTHOR]

Synergetic effects in Au–Ag bimetallic nanoclusters (BNCs) more favorably enhanced electrochemical redox induced electrochemiluminescence (ECL) over photoexcitation induced photoluminescence (PL); this not only led to Au–Ag BNCs with enhanced bandgap-engineered ECL compared to Au NCs, but it also generated surface-defect related ECL to enhance the total ECL intensity. [ABSTRACT FROM AUTHOR]

The decline in female fertility as age advances is intricately linked to the diminished developmental potential of oocytes. Despite this challenge, the strategies available to enhance the quality of aged oocytes remain limited. Epigallocatechin‐3‐gallate (EGCG), characterised by its anti‐inflammatory, antioxidant and tissue protective properties, holds promise as a candidate for improving the quality of maternally aged oocytes. In this study, we explored the precise impact and underlying mechanisms of EGCG on aged oocytes. EGCG exhibited the capacity to enhance the quality of aged oocytes both in vitro and in vivo. Specifically, the application of EGCG in vitro resulted in noteworthy improvements, including an increased rate of first polar body extrusion, enhanced mitochondrial function, refined spindle morphology and a reduction in oxidative stress. These beneficial effects were further validated by the improved fertility observed among aged mice. In addition, our findings propose that EGCG might augment the expression of Arf6. This augmentation, in turn, contributes to the assembly of spindle‐associated F‐actin, which can contribute to mitigate the aneuploidy induced by the disruption of spindle F‐actin within aged oocytes. This work thus contributes not only to understanding the role of EGCG in bolstering oocyte health, but also underscores its potential as a therapeutic intervention to address fertility challenges associated with advanced age. [ABSTRACT FROM AUTHOR]

• A sensitive HPLC–MS/MS method for 5 steriod hormones with PBS as a blank surrogate was developed. • The absolute reference concentrations of ASD, Ts, DHEA, DHT, and P in human serum were provided. • The concentrations of 5 steriod hormones were compared with reference data used in clinical practice. Steroid hormones play an essential role in regulating physiological and reproductive development throughout the lifetime of an individual. One of the difficulties in determining endogenous substances is the lack of a blank matrix. Especially when the level of analytes is lower than the level in the so-called blank matrix. In the present study, an optimized HPLC-MS/MS method was developed and validated to quantify androstenedione (ASD), testosterone (Ts), dehydroepiandrosterone (DHEA), 5α-dihydrotestosterone (DHT), and progesterone (P) in serum samples from healthy people using PBS (pH = 7.4) as the blank surrogate matrix. Simultaneously, the method investigated the characteristics of NaCl, bull serum albumin, pure water as surrogate matrices for the analysis of steroid hormones. The data showed that the matrix effects of ASD, Ts, DHEA, DHT, and P in the same groups were not significantly different between PBS and twice charcoal-stripped serum (CS 2 S) as a blank surrogate matrix. Furthermore, the LLOQ using PBS as the blank matrix was up to 0.005 ng/mL for ASD, Ts, and P and 0.05 ng/mL for DHEA and DHT. The reference ranges of concentration (C PBS) of 5 steroid hormones were provided. Compared to the concentration with CS 2 S (C CSS) as the blank surrogate matrix, the relative biases (RBs) of Ts, DHT, P, and DHEA were finally stabilized at approximately −0.7%, −15%, −1.2%, and 9.2%, respectively. The results suggest that, in the cases of special required, the developed HPLC-MS/MS method can be used to determine the absolute concentration of 5 hormones in biological samples with PBS as the blank surrogate matrix. [ABSTRACT FROM AUTHOR]

• Freeze process significantly promoted the oxidation of iodide. • Freeze-induced DOM iodination produced a large number of organoiodine compounds. • Effects of pH, I– and O 2 content on I– oxidation and DOM iodization in frozen solutions were revealed. • DOM iodination products were mainly composed of aromatic structures. • DOM iodination process was primarily via substitution and addition reactions. Freeze-induced acceleration of I– oxidation and the consequent iodination of dissolved organic matter (DOM) contribute to the formation of organoiodine compounds (OICs) in cold regions. The formed OICs may be a potentially important source of risk and are very closely with the environment and human health. Herein, we investigated the acceleration effects of the freeze process on I– oxidation and the formation of OICs. In comparison to reactive iodine species (RIS) formed in aqueous solutions, I– oxidation and RIS formation were greatly enhanced in frozen solution and were affected by pH, and the content of I– and O 2. Freeze-thaw process further promoted I– oxidation and the concentration of RIS reached 45.7 µmol/L after 6 freeze-thaw cycles. The consequent products of DOM iodination were greatly promoted in terms of both concentration and number. The total content of OICs ranged from 0.02 to 2.83 µmol/L under various conditions. About 183–1197 OICs were detected by Fourier transform ion cyclotron resonance mass spectrometry, and more than 96.2% contained one or two iodine atoms. Most OICs had aromatic structures and were formed via substitution and addition reactions. Our findings reveal an important formation pathway for OICs and shed light on the biogeochemical cycling of iodine in the natural aquatic environment. [Display omitted] [ABSTRACT FROM AUTHOR]

Correction for 'Mechanistic investigations into synergistically enhanced radiative-charge-transfer in Au–Ag bimetallic nanoclusters' by Jianbo Liu et al., Chem. Commun., 2020, 56, 5665–5668, DOI: 10.1039/D0CC02047H. [ABSTRACT FROM AUTHOR]

Abstract: Sn doped lithium nickel cobalt manganese composite oxide of LiNi3/8Co2/8Mn3/8−x Sn x O2 (0≤ x ≤0.10) was synthesized by stannum substitute of manganese to enhance its rate capability at first time. Its structure and electrochemical properties were characterized by X-ray diffraction (XRD), SEM, cyclic voltammetry (CV), galvanostatic intermittent titration technique (GITT) and charge/discharge tests. LiNi3/8Co2/8Mn3/8−x Sn x O2 had stable layered structure with α-NaFeO2 type as x up to 0.05, meanwhile, its chemical diffusion coefficient D Li of Li-ion was enhanced by almost one order of magnitude, leading to notable improvement of the rate capability of LiNi3/8Co2/8Mn3/8O2. The compound of x =0.10 showed the best rate capability among Sn doped samples, but its discharge capacity reduced markedly due to secondary phase Li2SnO3 and increase of cation-disorder. The compound with x =0.05 showed high rate capability with initial discharge capacity in excess of 156mAhg−1. It is a promising alternative cathode material for EV application of Li-ion batteries. [Copyright &y& Elsevier]

Introduction: Frozen embryo transfer is associated with a higher rate of live birth and a lower risk for ovarian hyperstimulation syndrome in women with polycystic ovary syndrome (PCOS) compared with fresh embryo transfer. The aim of this study is to assess the optimal endometrial preparation protocol for women with PCOS undergoing frozen embryo transfer. Material and methods: We conducted a historical cohort analysis of 1720 women with PCOS who underwent the "freeze‐all" strategy between August 2014 and August 2017 because of their high risk for ovarian hyperstimulation syndrome. Three endometrial preparation protocols were used: natural cycle (NC; n = 191), which relies on the dominant follicle to secrete estrogen that then promotes endometrial growth; ovarian stimulation (OS; n = 96), which induces follicle growth using low doses of human menopausal gonadotropin; and hormone replacement (HRT; n = 1433), which uses exogenous estradiol to promote endometrial growth. The primary outcome was live birth. Results: For women who received a single embryo transfer, the live birth rates for the NC, OS, and HRT groups were 62.4%, 65.0%, and 52.2%, respectively. The live birth rate in the HRT group was significantly lower than that seen in the OS and NC groups (P =.009). The clinical pregnancy rates of the three groups were 72.3%, 73.8%, and 64.9%, respectively; this difference did not reach statistical significance (P =.071). Conclusions: The rate of live birth with the NC and OS regimens was higher than with the HRT protocol in women with PCOS who undergo single‐blastocyst frozen embryo transfer. [ABSTRACT FROM AUTHOR]

Quinolone antibiotic residues may pose potential threat to human health. A rapid and sensitive method was developed for the determination of quinolone residues in human serum and urine. After solid phase extraction (SPE) process, eight quinolone residues were analyzed by high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) using ciprofloxacin-d8 as the internal standard. The relative standard deviation of intra-day and inter-day precision for the eight quinolones were less than 7.52% and the accuracies ranged from 95.8% to 103% in human serum, and from 94.1% to 104% in human urine. The extraction recoveries for the eight quinolones varied from 80.2% to 113% in human serum and 83.4% to 117% in human urine. The limit of detection for the eight quinolones was 0.50–1.00 ng/mL. Quinolone antibiotic residues in human serum and urine from 12 volunteers were successfully analyzed with the validated method. The SPE-HPLC-MS/MS method was useful for accurate determination of quinolone antibiotic residues in human body. [ABSTRACT FROM AUTHOR]

In this research, epigenetic effects of bisphenol A (BPA) on human breast cancer MCF-7 cells were analyzed. Genome-wide DNA methylation and gene expression were analyzed in MCF-7 cells exposed to BPA (10−5 and 10−6 mol/L for 5 weeks). No significant changes in the global level of 5-methyl-2′-deoxycytidine and 5-hydroxymethyl-2′-deoxycytidine were observed. DNA methylation profiling analysis indicated that BPA exposure resulted in the hypermethylation of FOXK2, LKB1, LMX1A and CUGBP2 and the hypomethylation of PTPRN2, TRIM27, BCAS3 and ZNF423. Decreased expression of apoptosis genes (P38 and BCL2L1) and increased expression of chemokine (Cxcl2 and ccl20) were detected. Changes of these genes were speculated to affect the ERα-related cell growth as well as cell apoptosis. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs) were in-situ deposited onto the ordered mesoporous carbon (OMC) to function as a novel SPME coating. The specific area, pore volumes and average pore diameter for OMC and AuNP/OMC were calculated to be 411 and 281 m g, 0.93 and 0.69 cm g, 7.1 and 6.8 nm, respectively. The results indicate that the introduction of AuNPs greatly enhances the extraction of anilines, probably due to the strong interaction between gold and amino groups. The composite material was coated onto a fiber which then gave enrichment factors in the range from 1143 to 3420 for anilines, 45 to 845 for alcohols and 86 to 545 for phenols, indicating its extraction selectivity towards aniline. Following desorption, four anilines were quantified by gas chromatography with flame ionization detection. The method has low limits of detection (0.072-0.18 μg L) and a good precision (1.9-3.8%). It was successfully applied to the analysis of anilines in river and drinking samples. Recoveries range from 83.9% to 107.7% and 94.0 to 113.1%, respectively. [ABSTRACT FROM AUTHOR]

5-hydroxymethyl-2′-deoxycytidine (5-hmdC), which plays important roles in the epigenetic remodeling in mammals, has been recently determined in plant genomes at trace concentrations. In this study, a method for the sensitive, specific, and rapid assessment of 5-hmdC in rice is reported using high-performance liquid chromatography–tandem mass spectrometry (HPLC–tandem MS) with isotope dilution. The recovery of this method was from 75.6% to 81.3% for 5-hmdC and the intra- and inter-day precision values were within 5.81%. The quantification limit for 5-hmdC was 5.0 pM. Genomic DNA from rice was extracted and enzymatically digested for nucleotides for the HPLC–tandem MS assay. The 5-hmdC levels were 1.32 ± 0.08, 1.64 ± 0.12, and 1.98 ± 0.07 modifications per million nucleosides in the Shengdao-18, Shengxiang-145, and Jindao-263 rice cultivars. The application of HPLC–tandem MS for 5-hmdC demonstrated its presence in the genomic DNA of rice and is useful in further studying the role of modified cytosine in the epigenetic regulation of rice. [ABSTRACT FROM PUBLISHER]

Achieving both rapid adsorption rate and high adsorption capacity for bisphenol micropollutants from aquatic systems is critical for efficient adsorbents in water remediation. Here, we elaborately prepared three nitrogen-rich triazine-based porous polymers (NTPs) with similar geometric configurations and nitrogen contents (41.70–44.18 wt%) while tunable BET surface areas and micropore volumes in the range of 454.7–536.3 m2 g−1 and 0.20–0.84 cm3 g−1, respectively. It was systematically revealed that the synergy of hydrogen bonding, π−π electron-donor-acceptor interaction, and micropore preservation promoted the rapid (within 5 min) and high capacity adsorption of bisphenols by NTPs. Particularly, microporous-dominated NTPs-3 with the highest micro-pore volume (0.84 cm3 g−1) displays remarkable adsorption capacity towards bisphenol A as evidenced by the adsorption capacity of 182.23 mg g−1. A simple column filter constructed by NTPs-3 also expressed good dynamic adsorption and regeneration capacity. This work provided new insight into the rational design and engineering of nitrogen-rich porous polymers for the remediation of micropollutant wastewater. Three nitrogen-rich triazine-based porous polymers with similar geometric configurations and nitrogen contents while tunable BET surface areas and micropore volumes were used for the adsorption of bisphenol micropollutants. [Display omitted] • NTPs have similar geometric configurations and nitrogen contents while tunable porosities. • The adsorption mechanism is the synergy of hydrogen bonding, π−π interaction, and micropore preservation. • NTPs-3 expressed rapid and high capacity adsorption of bisphenols. • A simple column filter constructed by NTPs expressed good dynamic adsorption and regeneration capacity. [ABSTRACT FROM AUTHOR]

• TAPA-TFPB-COFs was simply synthesized at room temperature. • TAPA-TFPB-COFs were explored as sorbents for the SPE of PCAs. • The established SPE-HPLC-MS/MS method was sensitive and accurate. • This method satisfied the analyzation of PCAs in environmental water samples. The determination of traces levels of pesticide residue in water is crucial for monitoring water quality. In this study, covalent organic frameworks (COFs), namely TAPA-TFPB-COFs were prepared at room temperature (25 °C) and applied as adsorbents for the solid phase extraction (SPE) of phenoxy carboxylic acid herbicides (PCAs). The extraction was followed by analyzation using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Under the optimal conditions, ultrasensitive and specific analysis of PCAs in water samples was achieved. The method exhibited high sensitivity with low limits of detection (0.08–0.28 ng L−1), good linearity in the range of 1.00 to 200 ng L−1 and satisfactory repeatability (intra-day: 3.72–5.30%; inter-day: 2.02–4.04%). The method was successfully applied to the analyzation of trace PCAs in tap, well, and river water and the spiked recoveries were in the range of 81.1–112%. These results indicate that the SPE-LC-MS/MS technique with TAPA-TFPB-COFs as the SPE adsorbent is a promising technique for the detection of trace levels of PCAs in environmental water samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • K, P, O and S were innovatively simultaneously doped into g-C 3 N 4. • K, P, O, S-g-C 3 N 4 has 12.85 times higher yield of H 2 O 2 than g-C 3 N 4. • The degradation rate of TC by K, P, O, S-g-C 3 N 4 was 1.5 times higher than the pure. • Four elements doping can promote the charge transfer in g-C 3 N 4. • Negatively charged S introduced into the g-C 3 N 4 can facilitate the ·O 2 − production. Elemental doping can modulate the electronic and molecular structure of g-C 3 N 4 to improve its photocatalytic properties. In this study, potassium (K), phosphorus (P), oxygen (O), and sulfur (S) were doped into the g-C 3 N 4 photocatalyst (K, P, O, S/g-C 3 N 4), and the four-element doped photocatalyst was successfully prepared. UV–vis diffuse reflection spectroscopy, photoluminescence, and transient photocurrent revealed that the co-doping of g-C 3 N 4 with K, P, O and S broadens the visible response and accelerates the transfer of photogenerated charges. Under visible light irradiation, the H 2 O 2 concentration produced with K, P, O, S/g-C 3 N 4 was 12.85 times higher than that with g-C 3 N 4. Moreover, tetracycline (TC) can be effectively degraded by the photocatalyst in surface water. The degradation pathway of TC and the molecular structures of 12 intermediates were analyzed by liquid chromatography-mass spectrometry. The superoxide radical (·O 2 −) trapping-electron spin resonance (ESR) technique confirmed that ·O 2 − is the main active species in the system. Therefore, the four-element doping strategy adopted in this research proved the feasibility of increasing the amount of H 2 O 2 produced and degrading the antibiotics in natural water under visible light. [ABSTRACT FROM AUTHOR]

• Effective dual-emission CDs were synthesized via reasonable surface regulation. • The ratiometric sensing system for TNP was constructed based on DE-CDs. • Successfully realized the detection of TNP in tap and pond water samples. • The feasibility of biological application was verified by cell imaging experiment. Carbon dots (CDs) with dual emission property can provide a convenient way to construct a ratiometric fluorescent sensor, which contributes to accurate determination of the target analytes. In this work, we present a simple and effective route to prepare dual emission CDs (DE-CDs) through the solvothermal reaction of o-phenylenediamine and ethanolamine. Under the excitation of UV light, DE-CDs not only show two distinguishable fluorescent emission peaks (430 nm, 550 nm), but also exhibit good water solubility and ratio fluorescence stability. The synthesized DE-CDs were employed as a ratiometric fluorescent sensor for the sensitive and selective detection of 2,4,6-trinitrophenol (TNP). Under optimal analysis conditions, a good linear relationship was obtained with the TNP concentration range from 0.2 to 50 µM and the limit of detection can reach 50 nM. The proposed method was applied successfully for the TNP detection in real water samples with recoveries of 86.8–116.3%. Furthermore, cell imaging experiments confirm the feasibility of visualizing intracellular TNP in live HeLa cells. [ABSTRACT FROM AUTHOR]

In this study, a stable cadmium(II)-based metal-organic framework (MOF) material was designed and used as a sorbent for the dispersive solid-phase extraction ( d SPE) of polybrominated diphenyl ethers (PBDEs) in environmental water samples. Gas chromatography coupled with triple quadrupole mass spectrometer (GC–MS/MS), working in the negative chemical ionization mode, was used to quantify the target analytes. Characterization of the material was performed by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), elementary analyses (EA) and thermogravimetric analyses (TGA). The synthesized rod shape MOF is on the micro level in size and has excellent chemical and solvent stability. The extraction conditions, including the extraction time, temperature and ionic strength, were examined systematically using response surface methodology (RSM). Under optimized conditions, the method that was developed showed an excellent extraction performance. Good linearity ( R 2 > 0.99) within the concentration range of 0.25–250 ng L −1 was obtained. Low limits of detection (0.08–0.15 ng L −1 , signal-to-noise ratio = 3:1) and good precision (relative standard deviation <12%, n = 6) were achieved. The developed method was applied to analyze natural and spiked environmental water samples. [ABSTRACT FROM AUTHOR]

Nickel aluminum layered double hydroxides (LDHs) fabricated via sodium citrate (SC) assistant hydrothermal route were evaluated for removing p-nitrophenol from aqueous solutions. The characterization results indicate that the NiAl-LDHs nanoparticles have well-ordered layer structure with highly crystalline nature. The NiAl-LDH possessed hierarchically porous nanoarchitectures with high surface area (108.7 m 2 /g) and great pore volume (0.41 cm 3 /g). Meanwhile, interlamellar spacing of NiAl-LDH was increased to 0.73 nm, demonstrating that the citric acid ion was intercalated into NiAl-LDH in vertical alignment. The morphology of NiAl-LDH changed from a series of disordered growth hexagon nanosheets to the flower-like microspheres with modification of variable sodium citrate. The adsorption isotherms of p-nitrophenol on NiAl-LDHs obey the Langmuir equation. It is worthy to note that the NiAl-LDH modified by sodium citrate with the addition of 2.316 g exhibits excellent adsorption performance with the maximum p-nitrophenol adsorption capacity of 77.7 mg/g. [ABSTRACT FROM AUTHOR]

[Display omitted] • Atomic copper (I)-carbon nitride (Cu-CN) was constructed. • Cu-CN exhibits peroxidase-mimic catalysis and colloidal stability. • Cu-CN can detect PFOS selectively in the range of 0.07–3 μM with LOD of 14.9 nM. • Coordination effect and fluorophilic interaction are the detection mechanism. • Cu-CN detection platform can detect PFOS in real water samples with RSD ≤ 8.37%. Pursuing a selective and stable optical sensor for the reliable detection of perfluorooctane sulfonate (PFOS) is critical to controlling and reducing the risk of exposure to human. Here, we elaborately prepared an atomic copper(I)-carbon nitride (Cu-CN) peroxidase-mimic catalyst and therefore developed a reliable and accessible PFOS detection method. Well-distributed Cu(I) atoms are exclusively anchored within CN nanosized matrix as identified Cu-CN single-site active centers. Benefiting from the high peroxidase-mimic catalytic capability and colloidal stability, Cu-CN exhibits outstanding detection of PFOS selectively in the range of 0.07 to 3 μM coupled with the detection limit of 14.9 nM. The occupation of atomic Cu(I) specific catalytic sites caused by strong PFOS coordination and the fluorophilic interaction between PFOS should be responsible for the damping of TMB oxidation. Moreover, this detection platform was also used successfully to detect PFOS in three real water samples with RSD ≤ 8.37%. This well-established colorimetric sensing system based on peroxidase-mimic capability of single-atom catalyst is promising for the detection of other hazards in aquatic environment. [ABSTRACT FROM AUTHOR]

A simple synthesis route is reported for generation of hierarchically porous Zn/Al layered double hydroxides (LDHs) by using urea and trisodium citrate (TSC) as precipitating agent and structure-directing agent, respectively. The structure, morphology and textural properties of the as-prepared LDH solids were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and nitrogen adsorption-desorption techniques. It was found that the flowerlike Zn/Al-LDHs hierarchically porous assemblies were constructed from hexagonal nanosheets with different sizes. Pseudo-second-order kinetic model was turn out to fit the experimental data well. The adsorption data were better described using the Langmuir adsorption isotherm with excellent adsorption capacity of 98.7 mg/g towards parachlorophenol in water. [ABSTRACT FROM PUBLISHER]

Boron nitride hollow spheres with ultrathin-shells were synthesized and used as sorbents for dispersive solid-phase extraction of aromatic pollutants at trace levels from environmental water samples. Polychlorinated biphenyls (PCBs) were selected as target compounds. Sample quantification and detection were performed by gas chromatography–tandem mass spectrometry. Extraction parameters influencing the extraction efficiency were optimized through response surface methodology using the Box–Behnken design. The proposed method achieved good linearity within the concentration range of 0.15–250 ng L −1 PCBs, low limits of detection (0.04–0.09 ng L −1 , S/N = 3:1), good repeatability of the extractions (relative standard deviation, <12%, n = 6), and satisfactory recoveries between 84.9% and 101.0% under optimal conditions. Real environmental samples collected from rivers, local lakes, rain and spring waters were analyzed using the developed method. Results demonstrated that the hexagonal boron nitride-based material has significant potential as a sorbent for organic pollutant extraction from environmental water samples. [ABSTRACT FROM AUTHOR]

Boron nitride nanotube (BNNT) is a novel material that shows potential ability in capturing organic pollutants. In this study, BNNTs fixed on a stainless steel fiber by a sol-gel technique were used as sorbent for solid-phase microextraction. Five polycyclic aromatic hydrocarbons with different numbers of aromatic rings were selected as target analysts. Gas chromatography coupled with tandem mass spectrometry was used for detection and quantitative determination. Under optimized conditions, the experimental results show a wide range of linearity (1 to 1,000 ng L), less than 10.1 % repeatability of relative standard deviation, and low detection limits (0.08 to 0.39 ng L). In addition, the fabricated fiber offered good thermal and chemical stability. The proposed method was successfully applied for the analysis of real water samples, and satisfactory results were obtained with relative recoveries ranging from 80.2 to 116.8 %. The results demonstrated that BNNTs could be used as sorbent for the analysis of environmental pollutants at trace levels. [ABSTRACT FROM AUTHOR]

[Display omitted] • OPD as the sole substrate constructs a ratiometric fluorescence system. • CuO NPs have both oxidase and ascorbate oxidase mimetic activity in the system. • Successfully realized the detection of AA in human serum and diverse fruits. • Scanning measurement analysis is realized through the App on smartphones. Copper oxide nanoparticles (CuO NPs) as nanozymes have received extensive attention due to their numerous advantages such as water solubility and biomimetic effects. In this work, we combined the inherent oxidase and ascorbate oxidase mimetic activity of CuO NPs to construct a ratiometric fluorescence system for the detection of ascorbic acid (Vitamin C, AA) in serum and fruits. By feat of the dual mimic nanozymatic activity of CuO NPs, the sole substrate o-phenylenediamine (OPD) can be catalyzed to attain yellow fluorescent 2,3-diaminophenazine (oxOPD), while oxidized AA will react with the pristine OPD to form blue fluorescent product. This method has a sensitive response to AA with a good linear relationship in the concentration range of 1–150 μM and low detection limit of 0.16 μM. Practical sample detection of AA in human serum and fruits can be realized reasonably with the recovery rates between 84.83% and 87.28% and 88.53%-113.1%, respectively. More conveniently, the method can be successfully used for scanning measurement analysis through the associated application (ColorAssist) on smartphones and portable UV lamps. [ABSTRACT FROM AUTHOR]

There is an increase in demand to develop simple, convenient, and low-cost approaches for rapid and label-free detection of antibiotics. Herein, we propose a new principle for the detection of kanamycin using the surface-anchored liquid crystal (LC) droplets. The optical images of the LC droplets uniformly change from four-clover, uniformly dark, and dark cross appearance gradually with the increase of surfactant concentration. The detection of kanamycin is fulfilled with the aid of a cationic surfactant cetyltrimethylammonium bromide (CTAB) and a kanamycin aptamer. The LC droplets show uniformly dark appearance and four-clover appearance in the presence of the aqueous solutions of CTAB and CTAB/aptamer complex, respectively. However, the specific binding of kanamycin to its aptamer can release the CTAB, which induces the uniformly dark appearance of the LC droplets. A portable device is built to measure the optical luminance of the LC droplets. This system can detect kanamycin with a concentration below 0.1 ng/mL (~0.17 nM) and also allows the detection of kanamycin in real samples such as milk and honey. Therefore, it is very promising in the development of new types of LC-based sensors by the surface-anchored LC droplets assisted with a portable optical device. [Display omitted] • The surface-anchored liquid crystal droplets are employed as the sensing platform. • The detection is based on the transition between four-clover and uniform dark appearance. • A portable optical digital device is developed to measure the luminance of the LC droplets. • The minimum detection concentration of kanamycin reaches as low as 0.1 ng/mL (~0.17 nM). • The detection of kanamycin in real samples are successfully demonstrated. [ABSTRACT FROM AUTHOR]

• A novel magnetic covalent organic framework (NH 2 –Fe 3 O 4 @COF) was synthesized and used as a MSPE adsorbent. • Adsorption mechanism of benzoylurea insecticides (BUs) on NH 2 –Fe 3 O 4 @COF was elucidated by DFT study. • Low limits of detection, good precision, and wide linearities were obtained by the proposed MSPE–LC–MS/MS method. A novel magnetic covalent organic framework (NH 2 –Fe 3 O 4 @COF) was prepared using a simple room-temperature synthesis in this study. These magnetic particles exhibited high adsorption performance with short adsorption time (10 min) for six benzoylurea insecticides (BUs) as magnetic solid-phase extraction (MSPE) adsorbents. Quantum chemistry calculation demonstrated that adsorption mechanism was primarily attributed to strong halogen bonds between electronegative O atoms of COF and electropositive F atoms of BUs as well as potential hydrophobic effect. Wide linearities (10–1000 ng·L−1) and low limits of detection (0.06–1.65 ng·L−1) for six analytes were obtained via liquid chromatography–tandem mass spectrometry. Applicability of the proposed method was further evaluated by analyzing four kinds of original tea beverages. Recoveries of six BUs in spiked samples ranged from 80.1% to 108.4%. [ABSTRACT FROM AUTHOR]

Efficient adsorption of organic dyes from effluent has great importance for ecological and environmental protection. Herein, covalent triazine frameworks (CTFs) were constructed via the polycondensation of melamine and cyanuric chloride directly. Due to the numerous basic nitrogen atoms as high as 58.98 wt%, high BET surface area (670.2 m g−1), and hierarchical pore structure, CTFs demonstrated selective adsorption of anionic dyes in high capacity (e.g., a maximum adsorption capacity of 1581 mg g−1 for Congo red at 30 °C). The mechanism of the outstanding adsorption performance was carefully verified and ascribed to the electrostatic attraction and hydrogen bonding between CTFs and anionic dyes. The amine groups linking two adjacent triazine rings have primary responsibility for the superior performance. Unexpectedly, CTFs expressed a tuning synergetic effect for removing cationic dyes in aqueous solution coexisting with anionic dyes, exhibiting a great superiority in the specific and comprehensive treatment of organic dyes contaminated water. Furthermore, CTFs were stable and had long-periodic availability for more than 6 times, ensuring the adsorption rate higher than 90%. For better operation, hybrid monolithic aerogels were constructed by incorporating CTFs into polyvinylidene fluoride then casting in melamine resin foams. The obtained aerogels expressed high-efficient removal of anionic dyes coupled with convenient operation. This well-established metal-free porous material is a promising adsorbent candidate for anionic dyes selectively and even synergetic adsorption of cationic dyes in water remediation. [Display omitted] • Covalent triazine frameworks with numerous nitrogen atoms, high BET surface area, and hierarchical pore structure were constructed. • CTFs had selective adsorption of anionic dyes in high capacity. • The adsorption mechanism was verified to be electrostatic attraction and hydrogen bonding. • The amine groups (-NH-) in CTFs have primary responsibility for the superior adsorption performance. • CTFs expressed a tuning synergetic effect for removing cationic dyes coexisting with anionic dyes. [ABSTRACT FROM AUTHOR]

Water quality was highly affected by common pollutants. Metals, pesticides and small molecules are ubiquitous pollutants. Advancement in engineering technology (computer-based monitoring systems) increased the efficiency of quantifying toxicity of different chemicals in an organism. The cardiovascular system reflects internal and external stress of an organism, and electrocardiogram (ECG) data reliably measure external stress. As ECG data can accurately reflect the physiological conditions of organisms, and zebrafish (Danio rerio) are considered to be good models for cardiovascular research, it is hypothesized that ECG parameters of zebrafish could indicate the toxicity of water-borne chemicals. To achieve this, we treated zebrafish with different concentrations of target chemicals (CuSO 4 , C 10 H 19 O 6 PS 2 and NH 4 Cl) for 48 h and ECG data were measured. P-wave, R-wave, T-wave, PR-interval, QRS-complex and QT-interval data were the focus of this study. The results of self-organizing maps and Pearson correlation analysis indicate that the QRS-complex can be used as an indicator for CuSO 4 stress. The QT-interval could be used to assess the C 10 H 19 O 6 PS 2 stress. The QT-interval and P-wave can be used to evaluate the NH 4 Cl stress. Responses of zebrafish ECG parameters were identical with other vertebrate model, and were specific to toxicant types. It is proved that zebrafish heart ECG index could be used as a potential indicator in early detection of environmental stress. Image 1 • Zebrafish ECG index would be characteristically response to different types of pollutants. • QRS complex can be an effective indicator in assessing copper sulfate stress (r = 0.788, p = 0.00006). • Prolonged QT interval of zebrfish can be induced by malathion (r = 0.770, p = 0.0001). • QT interval with P wave could be used to evaluate NH 4 Cl stress (r > 0.6, p < 0.01). [ABSTRACT FROM AUTHOR]

• Asp-AuNPs were successfully synthesized by simple one-pot protocol. • The colorimetric sensing system of Cr3+ was constructed based on Asp-AuNPs. • Successful detection of Cr3+ in practical water samples was carried out. • Scanometric analysis was established to be suitable for Cr3+ field detection. In this work, we report an effective one-pot strategy for synthesizing aspartic acid-functionalized gold nanoparticles (Asp-AuNPs) and constructing chromium (III) ion (Cr3+) colorimetric sensing system. Aspartic acid, acting as a reductant and stabilizer, was used directly to synthesize functionalized AuNPs without additional surface modification procedure. The Asp-AuNPs possesses the same good stability and optical properties as citrate-stabilized AuNPs, which become a new option for preparing AuNPs. More importantly, aspartic acid exhibits superior performance than citrate and other succinic acid derivatives because of its Cr3+ identifying property. The Asp-AuNPs was used for the sensitive and selective detection of Cr3+ based on the aggregation-induced color change of AuNPs from wine red to blue-gray. Under optimal conditions, the absorbance ratios (A 660 nm /A 520 nm) show good linearity with Cr3+ concentrations with a limit of detection of 0.6 nM. Furthermore, the proposed method was applied for the analysis of Cr3+ in environmental water samples successfully with a reliable recovery of 95.4%-105.1%. Besides, the scanometric analysis model based on three primary colors change was established to deal with the requirement for the rapid quantitative determination of Cr3+ in environmental emergencies. [ABSTRACT FROM AUTHOR]

Graphene as a two-dimensional (2D) nanoplatform is beneficial for assembling a 2D heterojunction photocatalytic system to promote electron transfer in semiconductor composites. Here a BiVO4 nanosheets/reduced graphene oxide (RGO) based 2D-2D heterojunction photocatalytic system as well as 0D-2D BiVO4 nanoparticles/RGO and 1D-2D BiVO4 nanotubes/RGO nanocomposites are fabricated by a feasible solvothermal process. During the synthesis; the growth of BiVO4 and the intimate interfacial contact between BiVO4 and RGO occur simultaneously. Compared to 0D-2D and 1D-2D heterojunctions, the resulting 2D-2D BiVO4 nanosheets/RGO composites yield superior chemical coupling; leading to exhibit higher photocatalytic activity toward the degradation of acetaminophen under visible light irradiation. Photoluminescence (PL) and photocurrent experiments revealed that the apparent electron transfer rate in 2D-2D BiVO4 nanosheets/RGO composites is faster than that in 0D-2D BiVO4 nanoparticles/RGO composites. The experimental findings presented here clearly demonstrate that the 2D-2D heterojunction interface can highlight the optoelectronic coupling between nanomaterials and promote the electron–hole separation. This study will motivate new developments in dimensionality factors on designing the heterojunction photocatalysts and promote their photodegradation photocatalytic application in environmental issues. [ABSTRACT FROM AUTHOR]