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 : Triclosan (TCS), recognized as an endocrine disruptor, has raised significant concerns due to its widespread use and potential health risks. To explore the impact of TCS on lipid metabolism, both larval and adult zebrafish were subjected to acute and chronic exposure to TCS. Through analyzes of biochemical and physiological markers, as well as Oil Red O (ORO) and hematoxylin and eosin (H&E) staining, our investigation revealed that TCS exposure induced hepatic and intestinal lipid accumulation in larval and adult zebrafish, leading to structural damage and inflammatory responses in these tissues. The strong affinity of TCS with PPARγ and subsequent pathway activation indicate that PPARγ pathway plays a crucial role in TCS-induced lipid buildup. Furthermore, we observed a decrease in m6A-RNA methylation levels in the TCS-treated group, which attributed to the increased activity of the demethylase FTO and concurrent suppression of the methyltransferase METTL3 gene expression by TCS. The alteration in methylation dynamics is identified as a potential underlying mechanism behind TCS-induced lipid accumulation. To address this concern, we explored the impact of folic acid—a methyl donor for m6A-RNA methylation—on lipid accumulation in zebrafish. Remarkably, folic acid administration partially alleviated lipid accumulation by restoring m6A-RNA methylation. This restoration, in turn, contributed to a reduction in inflammatory damage observed in both the liver and intestines. Additionally, folic acid partially mitigates the up-regulation of PPARγ and related genes induced by TCS. These findings carry substantial implications for understanding the adverse effects of environmental pollutants such as TCS. They also emphasize the promising potential of folic acid as a therapeutic intervention to alleviate disturbances in lipid metabolism induced by environmental pollutants.

摘要 : In this study, zebrafish served as a model organism to meticulously investigate the toxicological effects of azithromycin (AZM) on larval development during acute exposure. Our research delineated several distinct pathological changes in the larvae, including spinal curvature, incomplete swim bladder development, and the formation of yolk cysts. Notably, profound neurological impacts were also observed, characterized by a significant reduction in the number of neurons within the zebrafish brain, diminished AChE activity, and disruptions in light-dark rhythms. Further investigation using the PharmMapper website identified potential AZM target genes. Subsequent GO and KEGG enrichment analysis unveiled the potential influence of AZM on zebrafish vascular and immune systems. Experimental validation substantiated these predictions, demonstrating that AZM exposure induces abnormal vascular branching and dysfunction in the immune system of zebrafish larvae.

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 : Fluorescence sensing technique has been used in environmental analysis due to its simplicity, low cost, and visualization. Although the fruit pulp-based biomass carbon quantum dots (CQDs) have excellent luminescent properties, aloe leaves possess the superiority of being easily accessible in all seasons compared to fruit pulp. Thus, we fabricated Aloe carazo leaf-based nitrogen doping-CQDs ( N -CQDs) using a facile hydrothermal approach, which emitted bright blue fluorescence with a quantum yield of 21.4 %. By comparison, the glutathione-encapsulated copper nanoclusters (GSH-CuNCs) displayed strong red fluorescence. A blue/red dual emission based on the N -CQDs/CuNCs mixture was established for nitenpyram detection. At the 350-nm excitation, the N -CQD/CuNCs system produced dual-wavelength emitting peaks at 440 and 660 nm, respectively. Moreover, when nitenpyram was introduced into the system, the fluorescence intensities (FIs) of N -CQDs significantly decreased, whereas the FIs of GSH-CuNCs varied slightly' simultaneously, the solution color changed from bright blue to dark red. Both the spectral overlapping between nitenpyram's UV–Vis absorption and N -CQDs' excitation and almost unchanged fluorescence lifetimes indicated the occurrence of inner-filtering effect (IFE) in the dual-emitting fluoroprobe. In addition, the Stern-Volmer constant ( K sv = 6.92 × 10 3 M −1 ), temperature effect, as well as UV–Vis absorption of N -CQD/CuNCs before and after the addition of nitenpyram corroborated the static-quenching behavior. Consequently, the fluorescence-quenching of N -CQDs by nitenpyram was attributable to the joint IFE and static-quenching principles. A good linearity existed between the F 660 /F 440 values and nitenpyram concentrations (0.5–200 μM) with a method detection limit of 0.15 μM. The dual-emitting fluoroprobe provided the satisfactory recoveries (95.0%–107.0 %) for nitenpyram detection in real-world waters, which were comparable with the results of traditional liquid chromatography coupled to tandem mass spectrometry method. Owing to its simple operations, low-cost, and adaptability for on-site outdoor monitoring, the newly developed dual-emitting fluoroprobe possesses great potential applications in routine monitoring of nitenpyram under field conditions.

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 : In this research, two typical environmental endocrine disruptors, triclosan(TCS) and bisphenol A(BPA) were selected as target chemicals and zebrafish (Danio rerio) were used as vertebrate model organisms. The effects of TCS and BPA on zebrafish neurodevelopment and locomotor behavior were investigated in detail. Results showed that both TCS and BPA induced phenotypic malformations in zebrafish embryos, such as pericardial edema, yolk cysts and swiming sac closure. Besides, their exposure inhibited the locomotor activity, damaged motor-related neurons and affected the activity of acetylcholinesterase in larval zebrafish, resulting in neurobehavioral disorders. Moreover, TCS and BPA both led to a decrease in the number of neonatal neuronal cells and an increase in apoptotic cells in zebrafish brain, which had a severe impact on the development of central nervous system. Target prediction combined with Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) cluster analysis was used to compare the similarities and differences between the metabolic pathways of TCS and BPA, as well as their underlying toxicity mechanisms. These findings provide an important theroretical reference for risk assessment and early warning of environmental exposure to TCS and BPA.

摘要 : By employing the datasets (GSE50718, GSE61186, and GSE89653) from the GEO database, the underlying transcriptomic data associated with zebrafish (Danio rerio) were rigorously extracted and analyzed. Through bioinformatics analysis, we identified the significantly differentially expressed genes (DEGs) in zebrafish when exposed to silver nanoparticles with varying sizes and coatings, and subsequently compared the quantity and expression trends of these DEGs. Consequently, the abundance of DEGs was in the following order:PVP-AgNPs-50nm > AgNO3 > PVP-AgNPs-150nm; Maltose-AgNPs > AgNPs. By virtue of the enrichment analysis (GO, KEGG, and GSEA), it was observed that under the exposure of silver nanoparticles, the DEGs were predominantly enriched in the immune-related pathways. In sharp contrast, silver nitrate primarily affected zebrafish cell cycle and metabolic pathways. These findings provided compelling evidence that a distinct difference in molecular mechanism existed between silver nanoparticles and silver nitrate. Also, the aforementioned results led us to infer that the toxicity of silver nanoparticles not only results from the release of silver ions, but also from their inherent "particle-specificity". Moreover, the surface coating of silver nanoparticles played an important role in modulating their toxicity. These insights provide valuable guidance and strategic suggestions for the safe and effective application of silver nanoparticles in various fields.