查找使用阿拉丁产品的科研文献

Garnering sensitivity: A horseradish peroxidase and MoS2@black phosphorene based electrochemical biosensor for glyphosate detection

Lisi Wang,Xiaoqing Li,Baoli Wang,Fan Shi,Brij Mohan,Mansoor Ahmad,Wei Sun

Glyphosate (GLY) is one of the most widely used herbicides, and the presence of its residues in food samples poses a threat to human health. Developing a monitoring system could help address food safety concerns. This study presents an innovative electrochemical sensing platform to detect GLY, which employs molybdenum disulfide (MoS 2 ) and black phosphorene (BP) nanocomposites (MoS 2 @BP) with horseradish peroxidase (HRP) for the working electrode modification. The MoS 2 @BP nanocomposite is synthesized using a hydrothermal method, and its characteristics are investigated through different methods including scanning electron microscopy, X-ray photoelectron spectroscopy, and X-ray diffraction methods. The presence of BP enhances electrical conductivity and increases specific surface area, while MoS 2 improves the electrochemical properties of the composites and provides a protective effect on BP. The modification of MoS₂@BP on the electrode surface helps to accelerate the direct electron transfer of HRP with enhanced electrochemical responses. Furthermore, the incorporation of amino acid residues from HRP significantly enhances the recognition of GLY, thereby improving the selectivity and sensitivity of this electrochemical sensor. The sensor operates effectively within a linear concentration range from 0.118 nmol/L to 20.65 μmol/L, with a low detection limit of 0.0393 nmol/L (3σ). Furthermore, the sensor is successfully applied to detect GLY in real cornmeal samples with satisfactory results, demonstrating its potential applications in food safety monitoring.

Synthesis of dendrimer functionalized adsorbents for rapid removal of glyphosate from aqueous solution

Dandan Guo,Nadeem Muhammad,Chaoyan Lou,Dan Shou,Yan Zhu

Recently, the growing abuse of glyphosate herbicides in agricultural production has caused widespread accumulation of glyphosate in the environment, which is threatening the health or life of human beings and animals. To solve this problem, novel dendrimer grafted adsorbents were proposed for the rapid and efficient removal of glyphosate from water samples. These adsorbents were synthesized by grafting poly(amidoamine) dendrimers (PAMAM) onto poly(styrene-divinyl benzene-glycidylmethacrylate) beads. The morphological structure and chemical composition of the adsorbents were investigated by SEM, the BET method, FTIR spectroscopy, XPS and elemental analysis. Batch adsorption experiments were performed in glyphosate standard solutions with different pH, temperatures, and initial concentrations. Under the optimized conditions, adsorption equilibrium was attained rapidly within 5 min. Experimental data were correlated well with the pseudo-second-order model and the Langmuir model. The effect of temperature was also discussed by the thermodynamic parameters. Unlike other glyphosate adsorbents, their adsorption capabilities could be easily controlled by varying the generation of PAMAM dendrimer used. In addition, regeneration experiments showed that the adsorbents exhibited good reproducibility. When applied in the purification of contaminated drinking water, the removal efficiency of the adsorbents could be more than 95%.

A highly sensitive EC-SERS sensor of PANI/RGO/Ag/Cu film for doubly detecting glyphosate residues in fresh fruit

Xishun Peng,Yiheng Yuan,Anjiang Lu,Cunwei Wang,Caizhen Zu,Haili Zhang,Zhongchen Bai

Glyphosate (Gly) residues in agricultural products have a serious health risk, so it is urgent to seek a sensitive and convenient method for recognizing Gly residues in food. In this study, we proposed an electrochemical surface-enhanced Raman spectroscopy (EC-SERS) sensor of polyaniline/reduced graphene oxide/Ag/Cu (PANI/RGO/Ag/Cu) film to detect Gly residues. The EC-SERS sensor of PANI/RGO/Ag/Cu film had a large specific surface area, which could increase the binding sites of cu 2+ /Gly clathrates for boosting specifically its SERS signal. Moreover, Ag/Cu nanoparticles on the surface of film could effectively increase the differential pulse voltammetry signal and SERS signal of Gly molecules. The limit of detection of EC-SERS sensor to Gly could reach 1.9 nM. In addition, the EC-SERS sensor we prepared could also sensitively identify Gly residues on fresh fruit peels. The PANI/RGO/Ag/Cu film we proposed in this paper has great potential for selective and accuracy detecting Gly residues in agricultural products.

Synthesis, Herbicidal Activity and Toxicity Evaluation of Secondary Ammonium Salts from Turpentine Oil for Sustainable Weed Control

Huanhuan Dong,Hongmei Zhang,Shichao Xu,Jing Wang,Songlin Dai,Yuxiang Chen,Liangwu Bi,Zhendong Zhao

Three series of secondary ammonium chloride from turpentine were synthesized and evaluated as botanical herbicides. The preemergence herbicidal activities against ryegrass ( Loliun multiflorum ) and barnyard grass ( Echinochloa crus-galli ) were investigated using water as the only solvent. Their toxicity was evaluated by cytotoxicity assays. Preliminary results demonstrated that the herbicidal performance of the prepared salts was similar or much higher than that of corresponding secondary amines and even commercial herbicide glyphosate. Promisingly, compound 14e containing a cyclohexyl-substituted p- menthene skeleton with an IC 50 value of 0.0014 mM against root growth of ryegrass showed 39-fold higher herbicidal activity than glyphosate. Besides, this compound was found to be nontoxic to human and animal cells, indicating the potential application as a water-soluble herbicide for ryegrass control. Graphical

Detection of herbicide glyphosates based on an anti-aggregation mechanism by using unmodified gold nanoparticles in the presence of Pb2+

Zhuangwei Zhou,Yujie Zhang,Jingyan Kang,Chen Dong,Ningyi Chen,Xing Li,Zhiyong Guo,Aiguo Wu

In this study, a new detection method for glyphosate (GPS) based on an anti-aggregation mechanism by using gold nanoparticles (AuNPs) is proposed. A certain amount of Pb2+ can cause the aggregation of AuNPs because of electrostatic interactions and the color of the solution changed from red to gray. However, in the presence of GPS, the above-mentioned process can be strongly hindered due to the chelation between GPS and Pb2+. Based on this anti-aggregation mechanism, the colorimetric detection method exhibits excellent sensitivity for GPS. The limit of detection (LOD) is 0.5 μM by the naked eye and 2.38 nM by UV-vis spectroscopy. The selectivity of the AuNP detection system for GPS is excellent compared with other pesticides. A good linear relationship (R2 = 0.99695) between the absorption intensity ratio and GPS concentrations indicates that our probe can be used for the quantitative assay of GPS. The detection method has been successfully used for detecting GPS in real environmental samples.

Three-dimensional porous chitosan gel microspheres loaded with Ni and La for the treatment of inorganic and organic phosphorus in the water environment

Yue Zhou,Fangbin Lin,XiaoDong Wang,Hui Wang,Bingchun Xue

The development of adsorbents with high adsorption capacity and wide adaptable pH range was crucial to effectively controlling of water environment pollution. In this study, three-dimensional porous chitosan gel microspheres loaded with Ni and La (Ni-La-CS) were prepared for the adsorption of excessive phosphorus. The performance was investigated using glyphosate isopropylamine salt (GIS) and KH 2 PO 4 , which were selected as representative substances for organic and inorganic phosphorus. Results showed that Ni-La-CS exhibited high phosphorus removal efficiency with wide adaptable pH range. The adsorption process was monomolecular layer chemisorption , and the adsorption was spontaneous and endothermic. The coexistence of F − promoted the adsorption of phosphorus, while Cl − , SO 4 2− , CO 3 2− and HCO 3 − inhibited the adsorption. The material retained stability even after 5 cycles and the actual phosphorus-containing wastewater with 3.13 mg·L −1 could be treated to meet Chinese first-class standard.

Organic Matter Micro-Interfaces Change Glyphosate Partitioning and Alter Active Glyphosate Degraders in Soils

Soil microorganisms are responsible for natural glyphosate dissipation. However, previous studies have largely focused on bulk soils, and the underlying microscale mechanisms remain poorly resolved. In this study, we investigated the physicochemical properties and glyphosate adsorption on two representative soil microinterfaces of particulate organic matter (POM) and mineral-associated organic matter (MAOM) and explored the change in the active glyphosate degraders using DNA stable-isotope-probing (DNA-SIP). Owing to the rough, open structure and accessible functional groups, POM displayed a higher glyphosate adsorption capability (9.41 mg/kg) than MAOM (6.75 mg/kg). Soil microorganisms significantly enhanced the conversion of glyphosate to aminomethylphosphonic acid. The active glyphosate degraders wereStreptomyces,Clostridium, andLysobacterin bulk soils,Streptomyces,Clostridium,Steroidobacter,Herbaspirillum,Lysobacter, andOpitutuson POM, andStreptomyceson MAOM, as revealed by DNA-SIP. POM harbored the highest diversity and abundance of the putative glyphosate degraders, behaving as the principal micro-interface coupling glyphosate retention and biodegradation. Our findings revealed distinct patterns of glyphosate retention and distributions of putative glyphosate degraders at POM and MAOM micro-interfaces, providing an interface-scale perspective on glyphosate fate in soil.

Kinetics of glyphosate degradation in glyphosate wastewater over nitrogen-doped activated carbon catalyst in an upflow fixed bed reactor

Xing Bo,Chen Honglin,Zhang Xiaoming

Catalytic wet oxidation (CWO) of glyphosate (PMG) wastewater over a nitrogen-doped activated carbon catalyst was performed in an upflow fixed bed reactor at mild temperature (35–125 °C) and oxygen partial pressure (0.05–0.25 MPa). The catalytic performance was characterized by PMG and organic phosphorus (OP) conversion. All CWO experiments were under kinetic control by choosing suitable average particle size (0.3 mm, 40–80 mesh) and gas flow rate (500 mL min −1 ). A power law kinetic model was developed to describe PMG and OP conversion, assuming first order kinetics with respect to PMG and OP. This model and its calculated parameters successfully predicted PMG and OP conversion. The obviously different rate constant and activation energy for PMG and OP conversion suggested that removal of the intermediate of aminomethylphosphonic acid is the control reaction for OP conversion. Finally, the competitive oxidation of formaldehyde was insignificant and this model also proved a satisfactory description for treatment of the real PMG wastewaters. OP conversion for the different PMG wastewaters can reach over 90% at mild conditions (125 °C, 0.2 MPa of oxygen partial pressure, 25 min of liquid space time).

Glyphosate detection based on Eu coordination polymer through competitive coordination

Linglong Yi,Shangzai Wu,Guojian Ren,Qi Zhou,Ping Li,Yuan Wang,Xudong Tian,Danfeng He,Qinhe Pan

Glyphosate is a widely used herbicide in agriculture, leading to residues in food and water environments. These residues have been associated with heart disease and neurotoxicity. Therefore, it is urgent to develop new types of sensors for the detection of glyphosate residues. Here, a new coordination polymer, named as HNU-89 , is synthesized by the assembly of Eu 3+ and coumarin-3-carboxylic acid (HCCA). Benefiting from the hydrophobic ligands, HNU-89 can maintain its structure at pH 2–11. In view of that phosphoric groups in glyphosate molecules can coordinate with Eu 3+ and compete with the HCCA ligand, according to the competitive coordination, the interaction weakens the red fluorescence of HNU-89 simultaneously enhancing the blue fluorescence of HCCA, which achieves the ratio fluorescence response for glyphosate detection. The limit of detection (LOD) is 0.08 ppm, meeting the requirements as a sensor. Furthermore, HNU-89 was utilized to detect glyphosate in soybean, corn, rice and tap water.

Glyphosate and urea co-exposure: Impacts on soil nitrogen cycling

Pengxi Li,Wangjing Zhai,Bingxue Li,Qiqi Guo,Yujue Wang,Yucheng Gu,Li Zheng,Fanrong Zhao,Xueke Liu,Peng Wang,Donghui Liu

Glyphosate, the most widely utilized herbicide, frequently coexists with nitrogen fertilizers such as urea in soil environments. Nitrogen cycling is a key process for maintaining soil ecological functions and nutrient balance. However, the effects of co-exposure to glyphosate and urea on this process have remained unclear. This study investigated the impact of co-exposure to glyphosate (10 mg/kg) and urea (260.87 or 347.83 mg/kg, equivalent to 180 or 240 kg N/ha) on soil nitrogen cycling through a 98-day incubation experiment. Soil nutrients, enzyme activities, bacterial community structure, and functional genes were analyzed. NH 4 + -N and NO 3 - -N contents significantly decreased by 44.70–53.43 % and 36.74–49.12 %, respectively. Co-exposure reduced bacterial diversity and altered nitrogen cycling genes, decreasing nifH while increasing amoA and nosZ , indicating reduced nitrogen input potential and increased inorganic nitrogen loss. Enzyme analysis confirmed excessive activation of nitrification and denitrification, lowering nitrogen availability. Partial least squares structural equation modeling (PLS-SEM) showed co-exposure indirectly decreased NH 4 + -N and NO 3 - -N via enhanced nitrate and nitrite reductase activities. The study highlights the complex interactions between herbicides and fertilizers in soil environments and underscores the need for further research to understand the implications for wider soil health and crop production in agriculture systems.

A molecularly imprinted polypyrrole for ultrasensitive voltammetric determination of glyphosate

Xu Jinmeng,Zhang Yan,Wu Kaiqing,Zhang Lina,Ge Shenguang,Yu Jinghua

The paper describes a molecularly imprinted polymer along with an electrochemical assay for voltammetric determination of glyphosate (GLY). A composite of urchin-like gold nanoparticles and Prussian Blue was electrodeposited on an indium/tin oxide (ITO) glass to serve as a low-potential redox mediator and an electron transfer carrier. Then, polypyrrole was imprinted with GLY to form a molecularly imprinted polymer on the surface of the ITO electrode. The modified electrode was characterized using cyclic voltammetry and scanning electron microscopy. Differential pulse voltammetry showed the device to display an excellent current response to GLY, with a response that is linear in the 400–1200 ng⋅mL −1 GLY concentration range. The limit of detection is 92 ng⋅mL −1 . The method was successfully applied to the determination of GLY in spiked samples. In our perception, this approach represents a powerful tool for simple, low-cost and rapid detection of GLY in food and in the environment. Schematic of a molecularly imprinted polymer along with an electrochemical assay for voltammetric determination of glyphosate. The method employs electrodeposited urchin-like gold nanoparticles and Prussian Blue as a low-potential redox mediator and an electron transfer carrier.

Developmental toxicity of glyphosate on embryo-larval zebrafish (Danio rerio)

Zhihui Liu,Yingying Shangguan,Penglin Zhu,Yousef Sultan,Yiyi Feng,Xiaoyu Li,Junguo Ma

Glyphosate (GLY) induces developmental toxicity in fish, but research on the toxicity mechanism is limited. In this study, zebrafish embryos were exposed for 120 hpf to 0.7, 7, and 35 mg L -1 GLY. The results show that GLY treatment induced developmental toxicity in the fish, including premature hatching, reduced heartbeats, pericardial and yolk sac oedema, swim bladder deficiency, and shortened body length, which was possibly due to a significantly decreased triiodothyronine (T3)/thyroxine (T4) ratio and the abnormal expression patterns of hypothalamic-pituitary-thyroid (HPT) ( crh , tshβ , tr  α , tr  β , and t tr ) and growth hormone/insulin-like growth factor (GH/IGF) axis-related genes ( gh , ghrα , ghrβ , igf1 , igf1rα , and igf1rβ ) in larvae exposed to GLY. In addition, GLY exposure altered the levels of SOD and CAT, increased ROS, promoted malondialdehyde (MDA) content, and significantly altered the levels of endoplasmic reticulum (ER) stress signalling pathway factors ( perk , eif2α , gadd34 , atf4 , ire1α , xbp1 , atf6 , hspa5 , and chop ), suggesting that GLY treatment induced oxidative injury and ER stress in the larvae. Further research showed that treatment with a higher concentration of GLY upregulated the levels of iNOS, IL-1β, and TNF-α while inhibiting the expression of IL-10 and TGF-β, suggesting that GLY causes an inflammatory reaction in the larvae. In addition, we also found that apoptosis was induced in the larvae, which was determined by acridine orange staining and abnormal expression of p53 , caspase-3 , -8 , and -9 . Taken together, our results demonstrate that GLY exposure altered the T3/T4 ratio, disturbed the expression patterns of HPT and GH/IGF axis-related genes, and induced oxidative and ER stress, inflammatory reactions, and apoptosis in the zebrafish larvae. This investigation contributes to improved understanding of the developmental toxicity mechanism of GLY in fish.