摘要 : Pyrethroids are widely used insecticides worldwide, while their on-site and rapid detection still faces technological challenges. Herein, an innovative detection mechanism was designed for deltamethrin, a typical kind of type II pyrethroids, based on a dual-emitting fluoroprobe consisting of NH 2 -SiQDs and Eu 3+ . Deltamethrin can rapidly hydrolyze into 3-phenoxybenzaldehyde (3-PBD) and react specifically with fluoroprobe, causing fluorescence quenching of SiQDs while maintaining the fluorescent stability of Eu 3+ . Building upon the above fluorescence-responsive principle, SiQDs@Eu 3+ provided satisfactorily dual-emitting signals, realizing the highly-selective and sensitive detection of deltamethrin. Correlation between the surface structure of SiQDs and their absorption spectra was in-depth unraveled by TD-DFT calculation and FT-IR analysis. As for the analytical performance, the recovery and LOD of deltamethrin in lettuce, provided by SiQDs@Eu 3+, were comparable or even superior over conventional chromatographic analysis. Meanwhile, an innovative smartphone-based optical device was developed, which greatly decreased errors caused by the previously reported smartphone-based fluorescence detection.

摘要 : Herein, we engineered a novel pH-responsive ratiometric assay by virtue of the composite system of Ce 3+ -enhanced glutathione-encapsulated copper nanoclusters (GSH-CuNCs-Ce 3+ ) and N-doped carbon quantum dots (N-CQDs). The GSH-CuNCs-Ce 3+ and N-CQDs were fabricated using one-pot chemical reduction and hydrothermal approaches, respectively, and their morphologies as well as physical and chemical properties were testified in detail by a series of characterization techniques. At 350 nm excitation wavelength, the GSH-CuNCs-Ce 3+ /N-CQDs system (GCC-NC) featured the 440/650 nm dual-emitting property. The ratios of fluorescence intensities (F 650 /F 440 ) demonstrated a strong pH-dependence from 3.0 to 5.0 with a coefficient of determination of 0.9982. Consequently, the GCC-NC system was feasible for constructing a pH-responsive dual-emitting fluoroprobe. Based on the catalytic effect of acetylcholinesterase on acetylcholine to yield acetic acid and further trigger varying solution pH, the as-constructed GCC-NC fluoroprobe was satisfactorily applied for detecting malathion. Under optimized conditions, the newly developed GCC-NC fluoroprobe supplied a wider linear range (0.25–200 μM), lower detection limit (0.075 μM), satisfactory recoveries (96.3–106.2%) and higher precision for malathion in several kinds of fruit juice samples. The fortified experiments by malathion's structural analogues and metal ions provided compelling evidence that this fluoroprobe had strong anti-interference capacity and high specificity for malathion. These findings render us to believe that the as-constructed pH-responsive dual-emitting fluoroprobe holds great promise in trace malathion assay in food matrices.

摘要 : Herein, a dual-emitting fluoroprobe was pioneered for the sensitive and selective detection of hydroquinone (HQ) in environmental waters, which was based on integration of a tailor-made fluorescent ionic liquid ([TBAOH][NA]) with Eu 3+ (([TBAOH][NA]/Eu 3+ ). HQ could substantially enhance the 365-nm fluorescence intensity (FI 365 ) of [TBAOH][NA]/Eu 3+, whereas no prominent variation ocurred in FI 615 . After HQ binding with [TBAOH][NA], the electronic structure of S1 was completely pi-pi, and the orbital overlap of the latter was much higher, thereby promoting photon transitions. After some key factors were optimized using a central-composite-design (CCD) approach, this fluroprobe provided a linear response from 0.5 to 100 μM and detection limit of 0.15 μM for HQ assay, which was comparable to analytical performance by conventional HPLC-DAD analysis. Overall, the prominent advantages of as-developed fluoroprobe lie in two aspects: (1) Employing the ratio of two well-resolved emission and significantly differential responses to HQ greatly enhance sensitivity and accuracy through a self-calibration system; and (2) [TBAOH][NA] has not only the superiority of "green solvent" like conventional ionic liquids, but also possesses strong luminescence signal owing to introducing 1-naphathoic acid as an anion into tetrapropylammonium hydroxide. Consequently, this dual-emitting fluoroprobe is endowed with great potential in on-site and outdoor HQ monitoring.

摘要 : Herein, glyoxylic acid (GA) was incorporated into the Fenton-like (Fe(III)/H 2 O 2 ) system to rigorously examine its impact on the degradation of organic pollutants . It was found that the degradation efficiencies of atrazine (ATR), ofloxacin (OFL), rhodamine B (RhB), and carbamazepine (CBZ) in the Fe(III)/GA/H 2 O 2 system were ∼95%, and the apparent ATR degradation rate constant (1.60 × 10 −2 min −1 ) was 4-fold as high as that (0.40 × 10 −2 min −1 ) in the Fe(III)/H 2 O 2 system at pH 3.6. The UV–vis spectral and cyclic voltammetry (CV) analyses demonstrated that GA could be used as a ligand and reductant to coordinate and reduce Fe(III), thereby promoting the Fe(III)/Fe(II) cycles in the Fenton-like process. Testing results for reactive oxygen species (ROS) confirmed that superoxide ions (•O 2 – ) and hydroxyl radicals (•OH) respectively undertake the Fe(III)/Fe(II) cycles and ATR degradation in the Fe(III)/GA/H 2 O 2 system. The reaction stoichiometric efficiencies (RSE) in the Fe(III)/GA/H 2 O 2 system (37.5%–76.9%) were significantly higher than those (2.8%–4.9%) in the Fe(III)/H 2 O 2 system within 180 min, and the maximum concentration of •OH in the Fe(III)/GA/H 2 O 2 system was 4.6 times that in the Fe(III)/H 2 O 2 system. A series of the important variables were optimized in detail, including solution pH, GA dosage, amount of Fe(III) and H 2 O 2 . These findings provide compelling evidence for the non-negligible role of GA in the processes of organic pollutants degradation based on the Fe(III)/Fe(II) cycles and radicals generation in the Fenton-like system.

摘要 : Immobilizing Fe-based nanoparticles on electron-rich biochar has becoming an attractive heterogeneous Fenton-like catalysts (Fe/BC) for wastewater decontamination. However, the insufficient graphitization of biochar causing low electron transfer and by slow H 2 O 2 activation limited its application. Herein, we firstly constructed FeS/biochar composite through all-solid molten salt method (Fe/MSBCs), which can provide strong polarization force and liquid reaction environment to improve carbonization. As expected, the obtained Fe/MSBCs exhibits high surface area and fast interfacial electron transfer between FeS and biochar. More importantly, the partially oxidized FeS (001) facet facilitate H 2 O 2 adsorption and thermodynamically easily decomposition into •OH. Such a synergistic effect endowed them excellent photo-Fenton degradation performance for methyl orange (MO) with large kinetic rate constants (0.079 min −1 ) and high H 2 O 2 utilization efficiency (95.9%). This study first demonstrated the critical regulatory role of molten salt method in iron-based biochar composites, which provide an alternative for H 2 O 2 activator in water pollutant control.

摘要 : Triclosan (TCS), a prevalent contaminant in aquatic ecosystems, has been identified as a potential threat to both aquatic biota and human health. Despite its widespread presence, research into the immunotoxic effects of TCS on aquatic organisms is limited, and the underlying mechanisms driving these effects remain largely unexplored. Herein, we investigated the developmental and immune toxicities of environmentally relevant concentrations of TCS in zebrafish, characterized by morphological anomalies, histopathological impairments, and fluctuations in cytological differentiation and biomarkers following both acute (from 6 to 72/120 hpf) and chronic exposure periods (from 30 to 100 dpf). Specifically, acute exposure to TCS resulted in a significant increase in innate immune cells, contrasted by a marked decrease in T cells. Furthermore, we observed that TCS exposure elicited oxidative stress and a reduction in global m 6 A levels, alongside abnormal expressions within the m 6 A modification enzyme system in zebrafish larvae. Molecular docking studies suggested that mettl3 might be a target molecule for TCS interaction. Intriguingly, the knock-down of mettl3 mirrored the effects of TCS exposure, adversely impacting the growth and development of zebrafish, as well as the differentiation of innate immune cells. These results provide insights into the molecular basis of TCS-induced immunotoxicity through m 6 A-RNA epigenetic modification and aid in assessing its ecological risks, informing strategies for disease prevention linked to environmental contaminants.

摘要 : We propose a new approach for detecting palladium using a two-photon fluorescent probe quenched by perchlorate . This newly developed method has the potential to overcome some of the limitations of the currently available methods for detecting palladium. This article provides a detailed introduction to the design and synthesis of fluorescent probe, as well as the fluorescence performance in aqueous solutions. The results demonstrate the probe is highly sensitive, selective, and efficient in detecting palladium. The study also includes a thorough analysis of the quenching mechanism of the probe by perchlorate, and obtained different results from previous literatures. Moreover, the probe can easily identify and differentiate between palladium being present in the valence states 0, + 2/+ 4, and accomplish detecting palladium in convoluted solutions such as wastewater, environmental water, Hela cells and zebrafish. Due to its excellent performance, using self-developed optical device, the possibility of detecting palladium in aqueous solutions based on smartphone was explored.

摘要 : Herein, we developed a ratiometric fluoroprobe by integrating okra-derived carbon quantum dots (CQDs) with amplex red (AR) using manganese dioxide nanosheets (MnO 2 NSs) as a medium. Fluorescence intensities (FIs) of CQDs were sharply quenched by MnO 2 NSs via an inner-filter effect processes, whereas the FIs of AR were significantly enhanced due to oxidation of AR to AR-ox by the oxidase-mimetic activity of MnO 2 NSs. Acetyrylcholinesterase hydrolyzed acetylthiocholine to produce thiocholine, and the decomposition of MnO 2 NSs to Mn 2+ by thiocholine led to the FI recovery of CQDs, but decreased FIs of AR-ox. Based on the above phenomenon and the inhibitory effect of dichlorvos (DDVP) on acetyrylcholinesterase activity, a novel ratiometric fluoroprobe for DDVP quantification was pioneered. Under optimized conditions, this fluoroprobe gave a wide linear range (4–120 μg/L), low detection limit (1.2 μg/L), and satisfactory fortification recoveries (90.0–110.0%), thereby providing good prospects for routine DDVP monitoring in foods.

摘要 : Organophosphorus flame retardants (OPFRs) are widely used in commercial products owing to their exceptional flame-retarding and plasticizing properties. However, OPFRs are also well recognized as emerging persistent organic pollutants (POPs) because of their environmental persistence, biological concentration, and potential toxicity. Thus, the accurate detection of OPFRs in environmental media is critical for analyzing their fate, transport, and ecological risk. However, very few OPFR detection methods are currently available, and the types of OPFRs detected may vary from site to site. In this study, matrix solid-phase dispersion extraction (MSPD), a simple, rapid, and versatile technique for preparing solid, semisolid, liquid, and viscous samples, was combined for the first time with gas chromatography-tandem mass spectrometry (GC-MS/MS) to analyze 10 OPFRs in soil, namely, tripropyl phosphate (TPrP), tri-n-butyl phosphate (TnBP), tri-iso-butyl phosphate (TiBP), tris(2-chloroisopropyl) phosphate (TCIPP), tris(2-chloroethyl) phosphate (TCEP), tris(1, 3-dichloro-2-propyl) phosphate (TDCPP), triphenyl phosphate (TPHP), 2-ethylhexyl diphenyl phosphate (EHDPP), triphenylphosphine oxide (TPPO), and trimethylphenyl phosphate (TCP). The GC-MS/MS system was equipped with a Bruker-5MS capillary column coupled with a triple quadrupole mass spectrometer operated in multiple reaction monitoring (MRM) mode. Prior to detection, a mixed standard solution was fortified with 10 ng of13C-PCB208 as an internal standard. The optimal conditions under which MSPD could achieve high selectivity for OPFRs were determined. In addition, single-factor analysis was used to examine the influence of the sorbent (i. e., C18, PSA, Florisil, GCB, and multiwalled carbon nanotubes (MWCNTs)) as well as the dosage, type, and volume of the eluent on the extraction efficiency of the method for the 10 OPFRs. When GCB and ethyl acetate were used as the adsorbent and solvent, respectively, during elution, high extraction recoveries for the OPFRs were achieved. Optimization via response surface methodology (RSM) was adopted to further analyze the impact of three key factors, namely, the adsorbent dosage, eluent volume, and grinding time, as well as their interactions, on OPFR recoveries. Under the optimal conditions of 0.3 g of GCB as the adsorbent, 10 mL of ethyl acetate as the eluent, and 5 min of grinding time, the relative average recovery of the OPFRs was 87.5%. Furthermore, the 10 OPFRs showed good linear relationships under five concentration gradients, with correlation coefficients greater than 0.998. The limits of detection (LODs) and quantification (LOQs) were calculated as signal-to-noise ratios (S/N) of 3 and 10, respectively, and found to be in the ranges of 0.006-0.161 and 0.020-0.531 ng/g, respectively. The performance of the proposed method was verified by determining the recoveries and relative standard deviations (RSDs) of the OPFRs in soils spiked at low, medium, and high levels (10, 20, and 100 ng/g, respectively). The recoveries of the OPFRs ranged from 70.4% to 115.4%, with RSDs ranging from 0.7% to 6.7%. Compared with the conventional accelerated solvent extraction (ASE) method, MSPD presents higher efficiency, simpler operation, and less solvent requirements. The developed method was applied to determine OPFRs in soil samples collected from different sites in Suzhou, including an electronics factory, an auto-repair factory, a paddy field, and a school field. The results revealed that the contents of OPFRs in the soils from the electronics and auto-repair factories were significantly higher than those in the soils from the paddy and school fields. The main pollutants in the soil samples collected from the electronics and auto-repair factories were TCIPP, TPPO, TCEP, and TDCPP. Moreover, the contents of these compounds were 5.30, 4.44, 4.54, and 4.20 ng/g, in soils from the electronics factory and 2.70, 3.93, 7.60, and 5.04 ng/g, in soils from the auto-repair factory. To the best of our knowledge, this study is the first to determine high concentrations of TPPO in industrial soils. Thus, the combination of MSPD and GC-MS/MS adopted in this study can provide useful insights into the detection of the 10 OPFRs in soil.

摘要 : The extensive utilization and potential adverse impacts of the replacement flame-retardant 2-Ethylhexyl Diphenyl Phosphate (EHDPP) have raised concerns. Currently, there is limited knowledge regarding the developmental, neurological, and immunotoxic consequences of EHDPP exposure, as well as its potential behavioral outcomes. In this study, we undertook a comprehensive examination and characterization of the toxic effects over the EHDPP concentration range of 14–1400 nM. Our findings unveiled that EHDPP, even at an environmentally relevant concentration of 14 nM, exhibited excitatory neurotoxicity, eliciting a 13.5 % increase in the swimming speed of zebrafish larvae. This effect might be attributed to the potential influence of EHDPP on the release of neurotransmitters like serotonin and dopamine, which, in turn, mediated anxiety-like behavior in the zebrafish larvae. Conversely, sublethal dose EHDPP (1400 nM) exposure significantly suppressed the swimming vigor of zebrafish larvae, accompanied by morphological changes, abnormal behaviors, and alterations in intracerebral molecules. Transcriptomics revealed the underlying mechanism. The utilization of pathway inhibitors reshaped the inflammatory homeostasis and alleviated the toxicity induced by EHDPP exposure, anchoring the pivotal role played by the TLR4/NF-κB signaling pathway in EHDPP-induced adverse changes in zebrafish behavior and neurophysiology. This study observed the detrimental effects of EHDPP on fish sustainability at environmentally relevant concentrations, highlighting the practical significance for EHDPP risk management. Elucidating the toxic mechanisms of EHDPP will contribute to a deeper comprehension of how environmental pollutants can intricately influence human health. © 2024 Elsevier B.V.