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Biosensors & Bioelectronics Jul 2024The metal-organic frameworks (MOFs) nanozyme-mediated paper-based analytical devices (PADs) have shown great potential in portable visual determination of phenolic...
The metal-organic frameworks (MOFs) nanozyme-mediated paper-based analytical devices (PADs) have shown great potential in portable visual determination of phenolic compounds in the environment. However, most MOF nanozymes suffer from poor dispersibility and block-like structure, which often prompts deposition and results in diminished enzymatic activity, severely hindering their environmental applications. Here, we proposed colorimetric PADs for the visual detection of dichlorophen (Dcp) based on its significant inhibitory effect on the two-dimensional (2D) MOF nanozyme activity. Specifically, we synthesized a 2D Cu TCPP (Fe) (defined as 2D-CTF) MOF nanozyme exhibiting excellent dispersibility and remarkable peroxidase-like (POD-like) activity, which could catalyze the oxidation and subsequent color change of 3,3',5,5'-tetramethylbenzidine even under neutral conditions. Notably, the POD-like activity of 2D-CTF demonstrated a unique response to Dcp because of the occupation of Fe-N active sites on the 2D-CTF. This property enables the use of 2D-CTF as a highly efficient catalyst to develop colorimetric PADs for naked-eye and portable detection of Dcp. We believe that the proposed colorimetric PADs offer an efficient method for Dcp assay and open fresh avenues for the advancement of colorimetric sensors for analyzing of phenolic toxic substances in real samples.
Topics: Metal-Organic Frameworks; Dichlorophen; Biosensing Techniques; Peroxidases; Peroxidase; Colorimetry; Phenols; Hydrogen Peroxide
PubMed: 38583355
DOI: 10.1016/j.bios.2024.116271 -
Environmental Research Jan 2024This study systematically investigated the variable main electrooxidation mechanism of chlorophene (CP) and dichlorophen (DCP) with the change of reaction conditions at...
This study systematically investigated the variable main electrooxidation mechanism of chlorophene (CP) and dichlorophen (DCP) with the change of reaction conditions at TiO anode operated in batch and reactive electrochemical membrane (REM) modes. Significant degradation of CP and DCP was observed, that is, CP exhibited greater removal efficiency in batch mode at 0.5-3.5 mA cm and REM operation (0.5 mA cm) with a permeate flow rate of 0.85 cm min under the same reaction conditions, while DCP exhibited a faster degradation rate with the increase of current density in REM operation. Density functional theory (DFT) simulation and electrochemical performance tests indicated that the electrooxidation efficiency of CP and DCP in batch mode was primarily affected by the mass transfer rates. And the removal efficiency when anodic potentials were less than 1.7 V vs SHE in REM operation was determined by the activation energy for direct electron transfer (DET) reaction, however, the adsorption function of CP and DCP on the TiO anode became a dominant factor in determining the degradation efficiency with the further increase of anodic potential due to the disappeared activation barrier. In addition, the degradation pathways of CP and DCP were proposed according to intermediate products identification and frontier electron densities (FEDs) calculation, the acute toxicity of CP and DCP were also effectively decreased during both batch and REM operations.
Topics: Dichlorophen; Adsorption; Water Pollutants, Chemical; Oxidation-Reduction
PubMed: 37951380
DOI: 10.1016/j.envres.2023.117612 -
Journal of Materials Chemistry. B Oct 2023Conventional nanozyme-based pesticide detection often requires the assistance of acetylcholinesterase. In this work, a CuCeTA nanozyme was successfully designed for the...
Conventional nanozyme-based pesticide detection often requires the assistance of acetylcholinesterase. In this work, a CuCeTA nanozyme was successfully designed for the direct colorimetric detection of glyphosate. Direct detection can effectively avoid the problems caused by cascading with natural enzymes such as acetylcholinesterase. By assembling tannic acid, copper sulfate pentahydrate and cerium(III) nitrate hexahydrate, CuCeTA nanoflowers were prepared. The obtained CuCeTA possessed excellent peroxidase-like activity that could catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to blue oxidized TMB in the presence of hydrogen peroxide. Glyphosate could effectively inhibit the peroxidase-like activity of CuCeTA while other pesticides (fenthion, chlorpyrifos, profenofos, phosmet, bromoxynil and dichlorophen) did not show significant inhibitory effects on the catalytic activity of CuCeTA. In this way, CuCeTA could be used for the colorimetric detection of glyphosate with a low detection limit of 0.025 ppm. Combined with a smartphone and imageJ software, a glyphosate test paper was designed with a detection limit of 3.09 ppm. Fourier transform infrared spectroscopy demonstrated that glyphosate and CuCeTA might be bound by coordination, which could affect the catalytic activity of CuCeTA. Our CuCeTA-based nanozyme system exhibited unique selectivity and sensitivity for glyphosate detection and this work may provide a new strategy for rapid and convenient detection of pesticides.
Topics: Peroxidase; Acetylcholinesterase; Colorimetry; Peroxidases; Coloring Agents; Pesticides; Glyphosate
PubMed: 37750214
DOI: 10.1039/d3tb01455j -
Journal of Biomolecular Structure &... Sep 2023To date, no approved drugs are available to treat the Zika virus (ZIKV) infection. Therefore, it is necessary to urgently identify potential drugs against the ZIKV...
To date, no approved drugs are available to treat the Zika virus (ZIKV) infection. Therefore, it is necessary to urgently identify potential drugs against the ZIKV infection. Here, the repurposing of 30 antiparasitic drugs against the NS2B-NS3 protease of the ZIKV has been carried out by using combined docking and molecular dynamics- (MD) simulations. Based on the docking results, 5 drugs, such as Amodiaquine, Primaquine, Paromomycin, Dichlorophene, and Ivermectin were screened for further analysis by MD simulations and free energy calculations. Among these drugs, Amodiaquine and Dichlorophen are found to produce the most stable complexes and possess relative binding free energies of about -44.3 ± 3.7 kcal/mol and -41.1 ± 5.3 kcal/mol respectively. Therefore, they would act as potent small-molecule inhibitors of the ZIKV protease.However, evaluations of biological and safety activities of these drugs against the ZIKV protease are required before their clinical use.Communicated by Ramaswamy H. Sarma.
PubMed: 37747074
DOI: 10.1080/07391102.2023.2255648 -
Chemosphere Apr 2023Microbes play a dominant role for the transformation of organic contaminants in the environment, while a significant gap exists in understanding the degradation...
Microbes play a dominant role for the transformation of organic contaminants in the environment, while a significant gap exists in understanding the degradation mechanism and the function of different species. Herein, the possible bio-degradation of triclosan in microbial fuel cell was explored, with the investigation of degradation kinetics, microbial community, and possible degradation products. 5 mg/L of triclosan could be degraded within 3 days, and an intermediate degradation product (2,4-dichlorophen) could be further degraded in system. 32 kinds of dominant bacteria (relative intensity >0.5%) were identified in the biofilm, and 10 possible degradation products were identified. By analyzing the possible involved bioreactions (including decarboxylation, dehalogenation, dioxygenation, hydrolysis, hydroxylation, and ring-cleavage) of the dominant bacteria and possible degradation pathway of triclosan based on the identified products, biodegradation mechanism and function of the bacteria involved in the degradation of triclosan was clarified simultaneously. This study provides useful information for further interpreting the degradation mechanism of organic pollutants in mixed flora by combining analysis microbiome community and degradation pathway.
Topics: Triclosan; Bioelectric Energy Sources; Biodegradation, Environmental; Bacteria; Microbiota
PubMed: 36739987
DOI: 10.1016/j.chemosphere.2023.137983 -
Chemosphere Dec 2022Cytotoxicity of non-polar narcotic chemicals can be predicted by quantitative structure activity relationship (QSAR) models, but the polar narcotic chemicals' actual...
Cytotoxicity of non-polar narcotic chemicals can be predicted by quantitative structure activity relationship (QSAR) models, but the polar narcotic chemicals' actual cytotoxicity exceeds the predicted values by their chemical structures. This discrepancy indicates that the molecular mechanism by which polar narcotic chemicals exert their toxicity is unclear. Taking advantage of Saccharomyces cerevisiae (yeast) functional genome-wide heterozygous essential gene knockout mutants, we here have identified the specific molecular fingerprints of two main chemical structure groups (phenols and anilines) of polar narcotic chemicals (dichlorophen (DCP), 4-chlorophenol (4-CP), 2, 4, 6-trichlorophenol (TCP), 3, 4-dichloroaniline (DCA) and N-methylaniline (NMA)) and one non-polar narcotic chemical 2, 2, 2-trichloroethanol (TCE). Especially, we identify 33, 57, 54, 46, 59 and 53 responsive strains through exposure to TCE, DCP, 4-CP, TCP, DCA and NMA with three test concentrations, respectively, revealing that these polar narcotic chemicals have more responsive strains than the non-polar narcotic chemical. Remarkably, we find that the molecular fingerprints of polar narcotic chemicals in different chemical structure groups are obviously varied, particularly phenols and anilines have their own specific molecular fingerprints. Interestingly, our results demonstrate that the molecular toxicity mechanisms of anilines are associated with DNA replication, but phenols are related with pathway of RNA degradation. Additionally, we find that the two knockout strains (SME1 and DIS3) and the three knockout strains (TSC11, RSP5 and HSF1) can specifically respond to exposure to phenols and anilines, respectively. Thus, they may be served as potential biomarkers to distinguish phenols from anilines. Collectively, our works demonstrate that the functional genomic platform of yeast essential gene mutants can not only act as an effective tool to identify key specific molecular fingerprints for polar narcotic chemicals, but also help to understand the molecular mechanisms of polar narcotic chemicals.
Topics: Aniline Compounds; Dichlorophen; Genes, Essential; Narcotics; Phenols; Ribonucleoproteins, Small Nuclear; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins
PubMed: 36087727
DOI: 10.1016/j.chemosphere.2022.136343 -
Environmental Pollution (Barking, Essex... Aug 2022Dichlorophenol (DCP), a commonly used fungicide and insecticide, is widely found in waters and wastewaters. Herein, the degradation of DCP by Ferrate (Fe(VI)) in...
Dichlorophenol (DCP), a commonly used fungicide and insecticide, is widely found in waters and wastewaters. Herein, the degradation of DCP by Ferrate (Fe(VI)) in different matrices was comprehensively investigated. In pure water, a complete removal of DCP was achieved in 300 s at [Fe(VI)]:[DCP] molar ratio of 2:1. The presence of HA (10 mg L) inhibited DCP degradation to a certain extent. A total of twenty degradation products were identified by HPLC/MS analysis. Based on these products, reaction pathways including the cleavage of C-C bridge bond, hydroxylation, and radical coupling were proposed. These reaction mechanisms were further rationalized by theoretical calculations. The analyses of Wiberg bond orders and transition state indicated that C-C bond was the most vulnerable site for cleavage, and C site was the most likely site for hydroxyl addition. Mulliken atomic spin densities distribution suggested that self-coupling products was easily generated via C-O-C coupling ways. Finally, the feasibility of applying Fe(VI) to degrade DCP (20 μM) in a municipal wastewater effluent and a lake water was evaluated and verified. The findings in this study are of relevance in designing Fe(VI)-based treatment strategy for chlorine-containing persistent pesticides.
Topics: Dichlorophen; Kinetics; Models, Theoretical; Oxidation-Reduction; Oxidative Stress; Phenols; Wastewater; Water; Water Pollutants, Chemical; Water Purification
PubMed: 35525513
DOI: 10.1016/j.envpol.2022.119394 -
Chemistry, An Asian Journal Jul 2022Titanate nanotubes (TNTs) were coated with a cyclic oligosaccharide (carboxymethyl-β-cyclodextrin, CM-β-CD) to obtain a photocatalyst (CM-β-CD-TNT) for efficiently...
Titanate nanotubes (TNTs) were coated with a cyclic oligosaccharide (carboxymethyl-β-cyclodextrin, CM-β-CD) to obtain a photocatalyst (CM-β-CD-TNT) for efficiently activating molecular oxygen and removing the target contaminant. The hydrophobic cavity and the large specific surface area of the photocatalyst provide abundant active sites for activating molecular oxygen. The free radical capture experiment and quenching experiment showed that cyclodextrin could facilitate adsorption and activation of molecular oxygen to produce O . Therefore, compared with the pristine TNT, CM-β-CD-TNT accelerated the oxidation efficiency of paracetamol (APAP) by 3.4 times. Moreover, the ring cleavage reaction induced by CM-β-CD-TNT effectively reduced the acute toxicity of wastewater containing APAP. Furthermore, 100% of bisphenol A (BPA), bisphenol S (BPS), phenol, 2,4-dichlorophen (2,4-DCP), and carbamazepine (CBZ) were degraded by CM-β-CD-TNT after 2.5 h ultraviolet (UV) light irradiation. This strategy provides a new dimension for the advanced treatment of organic wastewater by organic macrocyclic molecule-modified materials.
Topics: Acetaminophen; Nanotubes; Oxygen; Wastewater; beta-Cyclodextrins
PubMed: 35470547
DOI: 10.1002/asia.202200352 -
Environmental Science and Pollution... Sep 2022Binary composite of zerovalent iron and titanium dioxide (Fe/TiO) was synthesized for the catalytic removal of dichlorophene (DCP) in the presence of peroxymonosulfate...
Binary composite of zerovalent iron and titanium dioxide (Fe/TiO) was synthesized for the catalytic removal of dichlorophene (DCP) in the presence of peroxymonosulfate (PMS). The as-prepared composite (Fe/TiO) exhibits synergistic effect and enhanced properties like improved catalytic activity of catalyst and greater magnetic property for facile recycling of catalyst. The results showed that without addition of PMS at reaction time of 50 min, the percent degradation of DCP by TiO, Fe, and Fe/TiO was just 5%, 11%, and 12%, respectively. However, with the addition of 0.8 mM PMS, at 10 min of reaction time, the catalytic degradation performance of Fe, TiO, and Fe/TiO was significantly improved to 82%, 18%, and 88%, respectively. The as-prepared catalyst was fully characterized to evaluate its structure, chemical states, and morphology. Scanning electron microscopy results showed that in composite TiO causes dispersion of agglomerated iron particles which enhances porosity and surface area of the composites and X-ray diffraction (XRD), energy dispersive X-ray (EDX), and Fourier-transform infrared (FTIR) results revealed successful incorporation of Fe, and oxides of Fe and TiO in the composite. The adsorption-desorption analysis verifies that the surface area of Fe/TiO is significantly larger than bare Fe and TiO Moreover, the surface area, particle size, and crystal size of Fe/TiO was surface area = 85 m g, particle size = 0.35 μm, and crystal size = 0.16 nm as compared to TiO alone (surface area = 22 m g, particle size = 4.25 μm, and crystal size = 25.4 nm) and Fe alone (surface area = 65 m g, particle size = 0.9 μm, and crystal size = 7.87 nm). The as-synthesized material showed excellent degradation performance in synthesized wastewater as well. The degradation products and their toxicities were evaluated and the resulted degradation mechanism was proposed accordingly. The toxicity values decreased in order of DP1 > DP5 > DP2 > DP3 > DP4 and the LC values toward fish for 96-h duration decreased from 0.531 to 67.2. This suggests that the proposed technology is an excellent option for the treatment of antibiotic containing wastewater.
Topics: Animals; Anti-Bacterial Agents; Catalysis; Dichlorophen; Iron; Oxidative Stress; Peroxides; Titanium; Wastewater; Water
PubMed: 35445919
DOI: 10.1007/s11356-022-20174-5 -
Journal of Hazardous Materials May 2022Despite the vital roles of Co nanoparticles catalytic oxidation in the Fenton-like system for eliminating pollutants, contributions of Co phases are typically...
Despite the vital roles of Co nanoparticles catalytic oxidation in the Fenton-like system for eliminating pollutants, contributions of Co phases are typically overlooked. Herein, a biphase Co@C core-shell catalyst was synthesized by the electrochemical co-reduction of CaCO and CoO in molten carbonate. Unlike the traditional pyrolysis method that is performed over 700 °C, the electrolysis was deployed at 450 °C, at which biphase structures, i.e., face-centered cubic (FCC) and hexagonal close-packed (HCP) structures, can be obtained. The biphase Co@C shows excellent catalytic oxidation performance of diethyl phthalate (DEP) with a high turnover frequency value (TOF, 28.14 min) and low catalyst dosage (4 mg L). Furthermore, density functional theory (DFT) calculations confirm that the synergistic catalytic effect of biphase Co@C is the enhancement for the breaking of the peroxide O-O bond and the charge transfer from catalysts to PMS molecule for the activation. Moreover, the results of radicals quenching experiments and electron paramagnetic resonance (EPR) tests confirm that SO, •OH, O, and O co-degrade DEP. Remarkably, 100% removals of three model contaminants, including DEP, sulfamethoxazole (SMX) and 2,4-dichlorophen (2,4-DCP), were achieved, either in pure water or actual river water. This paper provides an electrochemical pathway to leverage the phase of catalysts and thereby mediate their catalytic capability for remediating refractory organic contaminants.
Topics: Catalysis; Cobalt; Oxides; Peroxides; Water Pollutants, Chemical
PubMed: 35065308
DOI: 10.1016/j.jhazmat.2022.128287