Organic Pollutants In Environment Research Articles

Covalent Organic Framework Packed Nanoporous Membrane for Continuous Removal of Bisphenol A from Agricultural Irrigation Wastewater.

BPA, a typical endocrine disruptor, poses a significant threat to the growth of crops and thereby jeopardizes sustainable agriculture products and human health. In this work, a water-stabilized imine covalent organic framework (TpBD-COF) packed nanochannel membrane was constructed. The TpBD-COF membrane achieves high selective removal of BPA attributed to the subdivision of the pores by the filled COF, which further reduces the porous size and effectively eliminates the distance barrier between the selective sites of TpBD-COF membranes and BPA. The selective removal ratio of BPA was 5.79 times higher than that of the bare membrane, while the removal capacity reached 6.78 nM cm-2 min-1. It can eliminate BPA from irrigation wastewater and ensure crop growth. The application of COF-filled nanoporous membrane provides not only a size-matching strategy for the development of specific continuous removal of BPA but also a theoretical reference for membrane removal of other organic pollutants in agricultural irrigation water environment.

Selective degradation of organic pollutants in the aquatic environment by microplastic-derived dissolved organic matter through molecular photoresponse sequence transformation

The photochemical behavior of microplastics (MPs)-dissolved organic matter (PDOM) has received considerable attention, the molecular mechanism by which it undergoes photoresponsive transformation to generate reactive oxygen species (ROS) for the removal of organic pollutants remains unclear. This study combines fluorescence, mass spectrometry, and theoretical models to analyse the differences in the molecular mechanisms of PDOM, biochar-DOM (BDOM) and soil-DOM (SDOM) photoresponsive releasing ROS for selective degradation of organic pollutants. During the photoresponse process, molecular compounds in DOMs mainly undergo demethylation, decarboxylation, deoxygenation reactions to selectively degrade organic pollutants. However, differences in DOMs’ molecular structure composition and transformation patterns lead to varying ROS production. BDOMs containing higher proportion of aromatic compounds (26.68 %) exhibit stronger photoreactivity, resulting in better degradation efficiency of pollutants (>90 %). The high selectivity of PDOM for degradation of organic pollutants stems from the interconversion mode between its high and low oxygen compounds. PDOM degrades large molecular pollutants into less biotoxic small molecular intermediates through both radical and non-radical pathways, thereby reducing environmental hazards (1.5–948 times) posed by pollutants. The results show that although MPs is harmful to aquatic environment, it plays a positive role in regulating the structure of organic carbon pool and reducing environmental risks of other pollutants.

Persistent organic pollutants in the Antarctic marine environment: The influence impacts of human activity, regulations, and climate change

This study investigates the presence, distribution, and potential impacts of perfluoroalkyl substances (PFASs) and hexabromocyclododecanes (HBCDs) on the Antarctic marine environment. The analysis results from the King Sejong Station, the Jang Bogo Station, and Cape Evans revealed the highest concentrations of both PFASs and HBCDs at King Sejong Station, indicating the significant influence of human activity. Short-chain perfluorocarboxylic acids (PFCAs) dominated the seawater samples, with PFPeA at the highest concentration (0.076 ng/L) at King Sejong Station, whereas perfluorosulfonic acids (PFSAs) were prevalent in the sediments, with PFHxS reaching 0.985 ng/g. Total PFASs in benthos ranged from N.D. to 2.40 ng/g ww across all stations. This indicated the effects of long-range transport and glacial meltwater. α-HBCD was the most common diastereomer in benthos samples, detected in 58.3% of samples, suggesting its selective persistency. Although risk quotient analysis revealed low immediate risks to lower-trophic organisms, potential risks remain owing to their persistence and bioaccumulation potential. Contaminant patterns changed after regulations: perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) levels decreased, unregulated PFASs increased, HBCD stereoisomer ratios shifted towards α-HBCD dominance, and overall HBCD concentrations declined. Widespread persistence of regulated substances was observed in Antarctic environments, highlighting the need for comprehensive and long-term monitoring strategies. This study provides essential baseline data on contaminant distributions across the Southern Ocean, contributing to our understanding of emerging pollutants in Antarctic regions and informing future environmental protection efforts.

Methods for Measuring Organic Carbon Content in Carbonate Soils (Review)

In world practice, the measurement of the mass fraction of carbon of organic compounds (Corg) in soils containing carbonates is carried out in various ways. An analysis of methods that allow solving this problem was carried out, including the latest approaches: thermogravimetry, differential scanning calorimetry, spectroscopy. It has been shown that the presence of CaCO3 does not prevent the use of the dichromatometric method (Tyurin, Walkley-Black) for determining Corg. The disadvantages of the method boil down to the laboriousness of the analysis, the need for constant presence of the operator, incomplete oxidation of organic compounds and environmental pollution. The method of measuring soil mass loss-on-ignition (LOI) is economical and rapid, but it gives an overestimated Corg content, which is associated with the inadequacy of the conversion factor of 1.724, the presence of adsorbed and chemically bound water, as well as mineral components decomposing at T = 105–550°С. The most relevant solution for finding Corg in carbonate soils is to use an analyzer and a calcimeter, although the accuracy of Corg measurements in the presence of carbonates is significantly reduced due to the quadratic summation of the errors of the two methods. The high cost of the device, maintenance, verification and repair limit its widespread use in soil laboratories. To measure the content of soil carbonates, it is possible to use both gravimetric (LOI) and volumetric (calcimeter) methods. The use of the latter is preferable for soils with a predominance of CaCO3 in carbonate composition. Preliminary removal of carbonates from soil samples is labor-intensive and can lead to partial loss of Corg due to acid extraction. The high cost of instruments and the lack of libraries of soil spectra hinder the development of vis-NIR and MIR spectroscopy as an alternative to “wet” chemistry methods. Continuing comparative studies will improve the understanding of the spatial patterns of distribution of carbon in soil organic compounds.

Molecular Imprinting‐involving Highly Selective Tetracycline Detection Platform Based on Mn2V2O7 with Excellent Oxidase‐mimicking Activity

AbstractNanozymes‐involving colorimetry may represent an effective solution to tetracycline detection due to its affordability and simplicity. To improve the performance in selectivity, molecular imprinting technology has emerged as a promising approach to simulating the interaction between antibodies and receptors. Herein, Mn2V2O7, a form of nanozyme with oxidase‐mimicking activity, was synthesized. With tetracycline as the template, the cavities with unique dimensions were constructed through the self‐polymerization of dopamine (DA) on Mn2V2O7. In Mn2V2O7@MIP, polydopamine (PDA) acts as molecularly imprinted polymer (MIP) and its cavities are compatible with tetracycline in dimension. It also exhibits oxidase‐mimicking activity. With the introduction of tetracycline, the cavity of PDA is blocked, which leads to obvious color fading, which enables precise tetracycline detection with colorimetry. The range of linear detection is from 10 to 100 μM, and the lower limit of detection is 0.82 μM. It is anticipated that the combination between nanozymes‐involving colorimetry and molecular imprinting technology would contribute to the accurate detection of organic pollutants in the aquatic environment.

Piezocatalytic techniques and materials for degradation of organic pollutants from aqueous solution

With the rapid development of industry, agriculture, and urbanization, various organic pollutants have accumulated in natural water, posing a potential threat to both the ecological environment and human beings, and removing organic pollutants from water is an urgent priority. Piezoelectric techniques, with the advantages of green, simple operation, and high efficiency, are highly sought after in the degradation of environmental organic pollutants. Moreover, combining piezoelectric techniques with advanced oxidation processes (AOPs), photocatalysis, or electrocatalysis can further effectively promote the efficient degradation of target pollutants. Therefore, a perspective is presented on the recent progress of piezoelectric techniques for the degradation of various organic pollutants from aqueous solutions. The classification of various piezoelectric materials, as well as modification strategies for improving piezocatalysis, are first systematically summarized. Furthermore, the latest research on piezocatalysis and its combination with other technologies, such as AOPs, photocatalysis, and electrocatalysis, in the degradation of environmental pollutants is discussed. The potential mechanisms of piezocatalysis are also analyzed in depth. Finally, the urgent challenges and future opportunities for piezoelectric techniques in the degradation of organic pollutants are provided.

Polyoxometalate-based nanozyme with laccase-mimicking activity for kanamycin detection based on colorimetric assay.

As a kind of aminoglycoside antibiotics, kanamycin (KAN) is widely applied to animal husbandry and aquaculture. However, the abuse of KAN causes the large-scale discharge of it into rivers, lakes and groundwater, which threatens environmental safety and human health. Therefore, it is imperative to develop a method that is applicable to detect KAN in an efficient and accurate way. The colorimetric method based on enzymes provides a feasible solution for the detection of organic pollutants. However, the extensive application of natural enzymes is constrained by high cost and low stability. Herein, a polyoxometalate-based nanozyme, namely [H7SiW9V3O40(DPA)3]·4H2O (SiW9V3/DPA) (DPA = dipyridylamine), is synthesized. As a low-cost nanozyme with high stability compared to natural enzymes, SiW9V3/DPA performs well in laccase-mimicking activity. It can be used to induce chromogenic reaction between 2,4-dichlorophenol (2,4-DP) and 4-aminoantipyrine (4-AP), which generates red products. With the addition of KAN, the color fades. That is to say, KAN can be detected with colorimetric assay in the concentration range 0.1 to 100μM with high selectivity and low limit of detection (LOD) of 6.28μM.Moreover, SiW9V3/DPA is applied to KAN detection in lakeand riverwater and milk with satisfactory results. To sum up, polyoxometalate-based nanozyme is expected to provide a promising solution to the detection of organic pollutants in the aquatic environment.

Efficient adsorption of methyl red, methyl orange and bromothymol blue by polyamine resin: Role of linearity and size of carboxylate in enhanced encapsulation and molecular matching

Dyes constitute the major contribution to the environmental organic pollutants. Besides being hazardous to aquatic life, dyes are highly toxic and injurious to human health. Herein, we disclose the synthesis of a novel hyper cross-linked, dubbed as BPA-PEA, for the adsorptive removal of methyl red (MR), methyl orange (MO) and bromothymol blue (BTB). BPA-PEA displayed maximum adsorption capacities (qmax) for the adsorptive removal of these ionic dyes as 230.6 mg/g, 117.7 mg/g, and 80.42 mg/g for MR, MO and BTB, respectively. Density Functional Theory (DFT) simulations indicate a spontaneous binding process, with binding order closely aligns with the experimentally observed order (MR > MO > BTB). Moreover, the higher interaction in the resin-MR complex was believed due to the linearity and smaller size of the carboxylate group in the MR. Response Surface Methodology (RSM) optimization shows excellent suitability from their statistical parameter as well as low SSE value with the experimental values. The kinetic and isothermal data suggest that the adsorption process followed a chemisorption pathway and adsorption equilibrium was achieved within 2, 6, and 18 h for BTB, MR, and MO, respectively. A significant influence of pH was also observed in the adsorption of MO (5.5), MR (6.1), and BTB (5.3). The BPA-PEA was found to be thermally stable (Td = 348 °C) and mesoporous in nature, having a high surface area (78.3 m2 g−1). The adsorption mechanism is mainly governed by electrostatic interaction between the dyes and adsorbent, however, other adsorptive mechanism such as H-bonding interactions, hydrophobic interactions or π-π interactions were also involved. In addition, the adsorption efficiency of BPA-PEA was maintained for consecutive 5 cycles, with slightly decline (less than 5 mg/g for MR, MO, and BTB) in the adsorption capacity. Given the high adsorption capacity, short adsorption time, and reusability, BPA-PEA can serve as a promising adsorbent for the removal of anionic dyes from wastewater.

Photonic crystal-assisted sub-bandgap photocatalysis via triplet-triplet annihilation upconversion for the degradation of environmental organic pollutants

This study explores novel approaches to enhance photocatalysis efficiency by introducing a photonic crystal (PC)-enhanced, multi-layered sub-bandgap photocatalytic reactor. The design aims to effectively utilize sub-bandgap photons that might otherwise go unused. The device consists of three types of layers: (1) two polymeric triplet-triplet annihilation upconversion (TTA-UC) layers converting low-energy green photons (λEx = 532 nm, 2.33 eV) to high-energy blue photons (λEm = 425 nm, 2.92 eV), (2) a platinum-decorated WO3 layer (Eg = 2.8 eV) serving as a visible-light photocatalyst, and (3) a PC layer optimizing both TTA-UC and photocatalysis. The integration of the PC layer resulted in a 1.9-fold increase in UC emission and a 7.9-fold enhancement in hydroxyl radical (•OH) generation, achieved under low-intensity sub-bandgap irradiation (17.6 mW cm–2). Consequently, the combined layered structure of TTA/Pt-WO3/TTA/PC achieved a remarkable 38.8-fold improvement in •OH production, leading to outstanding degradation capability for various organic pollutants (e.g., 4-chlorophenol, bisphenol A, and methylene blue). This multi-layered sub-bandgap photocatalytic structure, which uniquely combines TTA-UC and PC layers, offers valuable insights into designing efficient photocatalytic systems for future solar-driven environmental remediation.

Tracing semi-quantitatively the absorption and removal of organic pollutants in human hair based on secondary ion mass spectrometry

Human hair has become a promising non-invasive matrix in assessing exposure to environmental organic pollutants (OPs). However, exogenous contaminants, which were absorbed into the hair via sweat, sebum, and air particles/dust, could contribute to OP levels in hair and interfere with the precise exposure assessment. So far, the microscopic mechanisms underlying the absorption of exogenous OPs into hair remain inadequately understood. This study focused on the in-situ investigation of the diffusion processes of exogenous OPs into the hair structure using secondary ion mass spectrometry (SIMS) and isotopic tracer techniques. Results showed that the relative signal intensities of deuterium-labeled tris(1,3-dichloro-2-propyl) phosphate (TDCPP), 1-hydroxypyrene (1-OH-Pry), and bisphenol A (BPA) in the hair cortex were notably elevated after a 6-hour exposure. Diffusion coefficients of contaminants were related to their molecular weight, and absorption volumes to their water solubility and molecular structures. Exposure duration and solvent influenced the rate of diffusion and absorption volumes. The distribution of deuterium-labeled molecules in exposed hair samples after washing with two different solvents (acetone or water) was similar to that before washing. Our findings revealed the diffusion of OPs in hair cross-sections, indicating exogenous contributions to contaminants that are biologically incorporated into the hair.

Solid phase extraction coupled with gas chromatography-triple quadrupole mass spectrometry for the rapid and simultaneous determination of forty-nine parent and halogenated polycyclic aromatic hydrocarbons in human serum

Halogenated polycyclic aromatic hydrocarbons (H-PAHs) are the emerging organic pollutants in environment, which are ubiquitous in the atmosphere, soil and water. Some H-PAH congeners have been proven to have dioxin-like toxicity. However, the research on the human internal exposure of H-PAHs is still limited. A simple and efficient analytical method is essential for the study of human internal exposure, so a method for the rapid and simultaneous determination of 16 polycyclic aromatic hydrocarbons (PAHs) and 33 H-PAHs in human serum was established in this study. After 1.0 mL serum was extracted with ethyl acetate/acetonitrile (1:4) solution containing 1 % formic acid, samples were purified by Captiva EMR-Lipid solid phase extraction column, and then determined by gas chromatography tandem triple quadrupole mass spectrometer (GC-MS/MS). The results showed that the recoveries of PAHs and H-PAHs ranged from 71.2 % to 119 % and 68.8 % to 121 %, respectively. When 1.0 mL of serum sample is used, the method detection limit of PAHs and H-PAHs is 0.001–0.314 ng/mL. The method is simple and efficient, and suitable for the simultaneous determination of trace PAHs and H-PAHs in human serum. High concentrations of chlorinated polycyclic aromatic hydrocarbons were detected in pooled serum, of which 1,5-dichloranthracene was the main contributor congener, with a concentration of 204–328 ng/g lipid, which deserved more attention.

Bioremediation of Some Organic Pollutants in the Aquatic Environment; the Egyptian and the Global Experiences

Bioremediation of Some Organic Pollutants in the Aquatic Environment; the Egyptian and the Global Experiences

Spinel CuBi2O4 integrated with boron nitride hexagons for a sensitive electro-analytical quantification of environmental organic pollutants

As organic pollutants are non-biodegradable, they pose a threat to the ecology and human health. Metol (MTL) is one of the most serious pollutants that gush into water sources. In this work demonstrates, a hydrothermal synthesized CuBi2O4 and ultrasonication approach for the construction of the Copper bismuth oxide/hexagonal boron nitride nanocomposite (CuBi2O4/hBN). Therefore, this consistent structure which enhance to strong interfacial interactions between the CuBi2O4 and hBN and also which facilitated the fast electron transfer efficiency in addition the physical and electrochemical characters of the CuBi2O4/hBN was characterize with supported by XRD, XPS, FE-SEM, HR-TEM, CV and DPV analysis. As a consequence, CuBi2O4/hBN/GCE surface modified electrode possessed a LOD of MTL 0.0052 µM at the sensitivity of 1.976 µA µM−1 cm−2 with 0.001 µM to 1987 µM linear rage. Furthermore, the feasibility of CuBi2O4/hBN/GCE to determine the MTL in the environmental water samples for instance pond, river, and tap water delivered a maximum recovery range about 97–99 % towards the detection of MTL. Therefore, CuBi2O4/hBN electrode material to attain superior electrochemical performances for the detection of MTL.

Self-powered organic pollutants degradation in wastewater by photocatalytic ozonation based on triboelectric nanogenerator

It is of great significance to explore innovative ways to degrade organic pollutants in wastewater. Here, for the first time, we report a self-powered photocatalytic ozonation water purification system for removing organic pollutants in aquatic environment. A rabbit fur-based rotary triboelectric nanogenerator (RR-TENG) is designed as the power supply of water purification system. As a new TENG-based ozone generation method, spark-surface dielectric barrier discharge (Spark-SDBD) is proposed, which is composed of spark discharge device and surface dielectric barrier discharge (SDBD) device in series and can generate ozone to a maximum concentration of 36.4 mg/m3. Rhodamine B and ciprofloxacin, two typical organic compounds, are selected as simulated pollutants in wastewater, and P25 particles loaded on nickel foam are used as the photocatalyst. Ozone is continuously introduced into the polluted solution through an aeration device, coupled with photocatalysis. Within 80 minutes, it can be observed that Rhodamine B has 100% decolorization and ciprofloxacin is degraded to 99%. This work broadens the field of water purification and provides an effective way to create a cleaner and safer aquatic environment.

Plasmon AgNPs/MoS2/ZnO nanorods array ternary heterojunctions enabling high-efficiency solar-light energy utilization for photocatalysis and recyclable SERS detection

BackgroundSurface-enhanced Raman scattering (SERS) has gained widespread use in molecule-level detection benefiting from its high sensitivity, nondestructive data acquisition, and capacity for providing molecular fingerprint information. However, the strong adhesion of target molecules to the substrate (known as the “memory effect”) inherently hinders the reusability of SERS substrates. Research has shown that self-cleaning SERS substrates based on versatile semiconductor materials with SERS enhancement capabilities and solar photocatalytic properties offer an effective platform for the sensitive detection and degradation of harmful molecules. ResultsIn this research, a resuable SERS-active substrate was facilely fabricated by anchoring silver nanoparticles (AgNPs) to the edges of MoS2 nanosheet decorated on ZnO nanorod arrays (NRAs). This innovative design exhibited a remarkable SERS enhancement factor (EF) of 4.6 × 107 and demonstrated significant solar photocatalytic efficiency. Such superior characteristics of ternary plasma heterojunction were ascribable to the synergistic effect of the “Schottky barrier” and “hot spots” between MoS2 and AgNPs, the inherent chemical enhancement proficiency of the MoS2/ZnO NRAs heterojunction, as well as the ultrafast electron transfer within the ternary heterojunction. SignificanceThe developed ternary heterojunction substrate enabled highly sensitive SERS detection of trace amounts of organic molecules. Moreover, this SERS substrate exhibited self-cleaning and recyclability via solar-light-driven photocatalysis. This bifunctional recyclable SERS substrate proved capable of meeting various requirements for routine monitoring of environmental organic pollutants and provided a robust avenue for advancing energy utilization materials that serve as high-performance SERS sensors and catalysts.

Micro(nano)plastics: invisible compounds with a visible impact.

The plastic related research has been an epicentre in recent times. The presence and spread of micro (nano) plastics (MNPs) are well-known in the terrestrial and aquatic environment. However, the focus on the fate and remediation of MNP in soil and groundwater is limited. The fate and bioaccumulation of ingested MNPs remain unknown within the digestive tract of animals. There is also a significant knowledge gap in understanding the ubiquitous organic environmental pollutants with MNPs in biological systems. Reducing plastic consumption, improving waste management practices, and developing environmentally friendly alternatives are some of the key steps needed to address MNP pollution. For better handling and to protect the environment from these invisible substances, policymakers and researchers urgently need to monitor and map MNP contamination in soil and groundwater.

Benzo[a]pyrene promotes an epithelial‐to‐mesenchymal transition process in MCF10A cells and mammary tumor growth and brain metastasis in female mice

AbstractBreast cancer is the most frequent neoplasia in developed countries and the leading cause of death in women worldwide. Epithelial‐to‐mesenchymal transition (EMT) is a cellular process through which epithelial cells decrease or lose their epithelial characteristics and gain mesenchymal properties. EMT mediates tumor progression, because tumor cells acquire the capacity to execute the multiple steps of invasion and metastasis. Benzo[a]pyrene (B[a]P) is an environmental organic pollutant generated during the burning of fossil fuels, wood, and other organic materials. B[a]P exposition increases the incidence of breast cancer, and induces migration and/or invasion in MDA‐MB‐231 and MCF‐7 breast cancer cells. However, the role of B[a]P in the induction of an EMT process and metastasis of mammary carcinoma cells has not been studied in detail. In this study, we demonstrate that B[a]P induces an EMT process in MCF10A mammary non‐tumorigenic epithelial cells. In addition, B[a]P promotes the formation of larger tumors in Balb/cJ mice inoculated with 4T1 cells than in untreated mice and treated with dimethyl sulfoxide (DMSO). B[a]P also increases the number of mice with metastasis to brain and the total number of brain metastatic nodules in Balb/cJ mice inoculated with 4T1 cells compared with untreated mice and treated with DMSO. In conclusion, B[a]P induces an EMT process in MCF10A cells and the growth of mammary tumors and metastasis to brain in Balb/cJ mice inoculated with 4T1 cells.

One-step process for debromination and mineralization of tetrabromobisphenol a by a layered double oxide-supported sulfurized nanoscale zero-valent iron under ambient conditions

Tetrabromobisphenol A (TBBPA), currently the most widely used brominated flame retardant, has attracted significant attention. However, traditional methods for deep debromination or mineralization of TBBPA usually include multiple steps and require external oxidants. In this study, we report a complete degradation of TBBPA through a one-step process of only adding a layered double oxide-supported sulfurized nanoscale zero-valent iron (S-nZVI@LDO) under ambient conditions. TBBPA was rapidly removed by S-nZVI@LDO with an efficiency of 95.6 % (10 mg⋅L-1) within 12 h. The kinetic rate constant (0.0035 min−1) was greater when compared with traditional reductants. The produced Br- ion occupied 76.7 % of total Br content, and the concentration of total organic carbon decreased by over 50 %, suggesting a deep debromination and mineralization of TBBPA by S-nZVI@LDO. It is caused by the substantial improvement of electron transfer, O2 adsorption, and hydrophobicity of S-nZVI@LDO facilitating synchronous reductive debromination and O2 activation to produce ·O2– and ·OH, as approved by electrochemical test, O2-TPO analysis, EPR analysis, and density functional theory calculations. The enriched structural S(−II) and enhanced Fe(III)/Fe(II) redox cycling exerted vital roles in maintaining the reduction potential of the composite. The degradation pathways analysis confirmed that debromination-mineralization mechanisms dominated the complete degradation of TBBPA. This study demonstrates the feasibility of the one-step mineralization removal of TBBPA only using S-nZVI@LDO under ambient conditions and offers insight into external oxidant-free in-situ elimination of halogenated persistent organic pollutants in a natural environment.

3D hierarchical flowerball-like CoSe2/MnSe nanosheet arrays as a novel electrode for electrochemical sensing of hydrazine

Hydrazine (N2H4) is considered to be a highly toxic substance harmful to human body and environment, and has received much attention in the field of electrochemical detection in recent years. In this study, 3D hierarchical flowerball-like CoSe2/MnSe nanosheet arrays (CoSe2/MnSe FNSAs) were obtained using CoMn-LDH as precursor and cobalt glycerate spheres as the sacrificial template by simple hydrothermal reaction and selenization method. Bimetal selenides have more active electrochemical activity and more abundant electrochemical redox reactions. The unique hierarchical flowerball-like nanosheet array heterostructure can accelerate ionic diffusion kinetics and improve electron transfer. As a hydrazine electrochemical sensor, CoSe2/MnSe FNSAs exhibits excellent electrocatalytic performance with a wide detection range of 0.001–7.45 mM and a low detection limit of 0.4 μM. This strategy provides a new choice for the detection of environmental organic pollutants.

Nanoremediation and Antioxidant Potential of Biogenic Silver Nanoparticles Synthesized Using Leucena's Leaves, Stem, and Fruits.

Synthetic dyes are persistent organic environmental pollutants that can cause extensive damage to living beings and to the ecosystem as a whole. Cost-effective, sustainable, and efficient strategies to deal with this type of pollution are necessary as it commonly resists conventional water treatment methods. Silver nanoparticles (AgNPs) synthesized using the aqueous extract from the leaves, stem, and fruits of Leucaena leucocephala (Leucena) were produced and characterized through UV-vis, TEM, EDS, SDL, XPS, XRD, and zeta potential, and they proved to be able to promote adsorption to remediate methylene blue and tartrazine pollution in water. The nanoremediation was performed and did not require direct exposure to sunlight or any special lamp or a specific reduction agent. The AgNPs produced using the extract from the leaves exhibited the best performance in nanoremediation and also presented antioxidant activity that surpassed the one from butylated hydroxytoluene (BHT). Consequently, it is an interesting nanotool to use in dye nanoremediation and/or as an antioxidant nanostructure.