Benzidine Research Articles

Interactions between Diphenylamine with 2-Hydroxypropyl β-Cyclodextrin based on Spectral, Biological and Theoretical Investigations

The inclusion complex of diphenylamine (DPA) in 2-hydroxypropyl β-cyclodextrin (HP-β-CD) was synthesized by a co-precipitation method. The structure and molecular properties of the newly synthesized inclusion complex (DPA: HP-β-CD) were investigated along with a β-cyclodextrin (β-CD) inclusion complex (DPA: β-CD) using various analytical and theoretical methods. Phase solubility, absorption, fluorescence, Fourier transform-Infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD) and scanning electron microscope (SEM) techniques were used to investigate the structural properties of the DPA before and after being encapsulated by the CDs (β-CD and HP-β-CD). Furthermore, the antioxidant and antibacterial activities were evaluated for DPA and the inclusion complexes (DPA: β-CD and DPA: HP-β-CD). The structure of the inclusion complexes was proposed based on the experimental results and their structural optimization was done using Becke’s three parameter density functional theory using Lee-Yang-Parr’s 3-21 G method in the gas phase. Then the various theoretical molecular properties, such as frontier molecular orbitals (FMO), molecular electrostatic potential map (MEP), Mulliken atomic charges, natural bond orbitals (NBO), electron localization function (ELF), localized orbital locator (LOL), quantum theory of atoms in a molecule (QTAIM) and noncovalent interactions—reduced density gradient (NCI-RDG) were studied for DPA and its inclusion complexes using the Gaussian 09 W software and Multiwfn 3.8 tool.

A disposable voltammetric sensor for the determination of diphenylamine using modified pencil graphite electrode.

This study reports the electrochemical monitoring and sensing of diphenylamine (DPA), an anti-scald agent on a modified pencil graphite electrode (PGE). DPA is also a potentially toxic environmental pollutant. A polymer of tyrosine synthesized by electrochemical process was utilized for the determination of DPA in real samples. The electrodes were characterized using IR, SEM, EDAX, AFM and EIS analyses. As far as we know, this is first time reporting the utilization of modified PGE via green approach for the monitoring of DPA. A dynamic linear range of 1.00-117.11µM with a lower detection limit (LOD) of 0.7050µM was showed by this sensor for the electrochemical quantification of DPA. The electrochemical oxidation of DPA on the modified sensor followed a mixed adsorption -diffusion controlled kinetics. The sensor also showed good anti-interference property for the determination of DPA in real samples. Furthermore, the developed sensor was applied for the selective sensing of DPA from real apple extracts with good recovery. The real sample analysis was validated with standard spectrophotometric method.

Electrocatalytic behavior of hydroxyapatite/graphene oxide nanocomposite-based sensor for electrochemical antioxidant monitoring of diphenylamine

Diphenylamine (DPA), a toxic pollutant in wastewater and food contaminants, has severe environmental impacts. In this study, a composite material comprising hydroxyapatite and graphene oxide (HAp/GO) was successfully prepared and used to modify a GCE electrode. This composite was employed to construct an electrochemical sensor to detect hazardous DPA. The physicochemical and electrochemical properties of the HAp/GO composite are well-characterized by various techniques. The developed sensor is affordable and biodegradable, offering high selectivity for DPA detection. A dynamic linear range of 0.005–249.685 µM was achieved through differential pulse voltammetry (DPV), with good sensitivity (0.536 µA µM−1. cm−2) and a low limit of detection (LOD, 0.009 µM). The synergistic combination of HAp and GO enhanced electrocatalytic performance, making this composite material a valuable electrocatalyst for sensitive and selective DPA detection, and it is applicable for detecting practical feasibility in real-world samples.

Metal Cation-Doped ns-Cucurbit[10]uril: Adsorption of Para-Phenylenediamine.

The separation of phenylenediamine (PDA) isomers is crucial in the field of chemical manufacturing. Herein, we presented a strategy for the separation of PDA isomers (para-phenylenediamine, p-PDA; meta-phenylenediamine, m-PDA; ortho-phenylenediamine, o-PDA) using four supramolecular framework materials of ns-cucurbit[10]uril (ns-Q[10]), (1) ns-Q[10](Cd), (2) ns-Q[10](Mn), (3) ns-Q[10](Cu), (4) ns-Q[10](Pb). Our findings indicated that these supramolecular framework materials of ns-Q[10] showed remarkable selectivity for para-phenylenediamine (p-PDA) in p-PDA, m-PDA, and o-PDA mixtures, respectively. The variations in selectivity observed in these four single-crystal structures arose from variations in the thermodynamic stabilities and binding modes of the host-guest complexes. Importantly, the supramolecular framework based on ns-Q[10] exhibited selective accommodation of p-PDA over its isomers. This study highlighted the practical application of ns-Q[10] in effectively separating PDA isomers and demonstrated the potential utility of ns-Q[10] in isolating other organic molecules.

Comparative Studies of Fatty Acid Methyl, Ethyl and i-Propyl Esters of Tamarindus indica Seed Oil as Biodiesel Base-Stock

The unsaturated fatty acids found in tamarind seed oil include oleic acid (16.0%), linoleic acid (56.0%), palmitic acid (8.0%) and stearic acid (4.0%). The free fatty acids (0.6%) present in the tamarind seed oil was converted to methyl, ethyl and isopropyl esters. Further, the base stocks were prepared by employing transesterification reaction catalyzed by a base. Biodiesel fuels thus prepared were evaluated for different parameters and methyl esters were found to show ester content (97.3%), density (0.86315 g/cm3), acid value (0.42), oxidation stability (1.49 h), flash point (137.2 °C) and kinematic viscosity (5.09 cSt), ethyl esters have shown a kinematic viscosity (5.54 cSt), density (0.87030 g/cm3), acid value (0.45), oxidation stability (2.16 h), flash point (141.2 ºC), ester content (97.7%) and isopropyl esters exhibited kinematic viscosity (20.05 cSt), density (0.9220 g/cm3), acid value (0.58), oxidation stability (0.05 h) and flash point (145.3 ºC). The study involved investigation of effectiveness of four different antioxidants namely, butylated hydroxyl toluene (BHT), butylated hydroxyl anisole (BHA), t-butyl hydroxyl quinone (TBHQ) and diphenylamine (DPA) in different concentrations to the prepared methyl and ethyl biodiesels. BHA and BHT were observed to exhibit enhanced oxidation stability of produced biodiesel. The physical and chemical properties of methyl and ethyl esters were found to lie within EN and ASTM specifications.

Assessment and usability of Jatropha biodiesel blend with phenolic antioxidant to control NOx emissions of an unmodified diesel engine.

The excessive utilization of fossil fuels has worsened global warming and exacerbated the levels of air pollution in the environment, forcing us to consider alternative fuels for compression ignition engines. The current research aims to explore the possibilities of renewable fuels outperforming diesel fuel in terms of combustion, performance, and emission characteristics. Biodiesel is an environmentally friendly and renewable alternative fuel. The major drawback of biodiesel is the significant rise in nitrogen oxide (NOx) emissions. The main novelty and objective of this research is to investigate the performance and emission characteristics of variable compression ratio diesel engine using DPA antioxidant additive. For this investigation, diesel, Jatropha biodiesel (B30) and 100 ppm of phenolic antioxidant diphenylamine (DPA) blended with B30 have been used as fuel named B30+DPA100. From experimental outcomes, the inclusion of diphenylamine to B30 blend resulted in brake-specific fuel consumption (BSFC) and exhaust gas temperature (EGT) being reduced by 8.86% and 4.12%, respectively, compared to B30. Simultaneously, there was a 1.11% increase in brake thermal efficiency (BTHE). The B30+DPA100 fuel blend demonstrates effective control over NOx and other emissions. The emissions of NOx, carbon monoxide (CO), hydrocarbon (HC), and smoke from the B30+DPA100 blend have shown a reduction of 6.8%, 5.34%, 7.86%, and 15.67%, respectively, when compared to diesel. However, there has been an increase in carbon dioxide (CO2) by 7.8%. One notable advantage of the B30+DPA100 blend is the significant decrease in NOx emissions. Additionally, the cylinder pressure for B30+DPA100 has been lowered by 4.93% compared to B30. On the other hand, the net heat release rate (NHR) has experienced a 1.72% increase. The particle size of different elements present in the crankcase oil has been calculated by Zetasizer Nano. The analysis revealed varying particle sizes for different elements in the crankcase oil: aluminum (2.724 μm), chromium (2.78 μm), iron (2.423 μm), and lead (2.587 μm).

Electroanalysis of ethyl-centralite propellant stabiliser at magnetic nanoparticle modified glassy carbon and screen-printed electrodes with extension to forensic firearm residue analysis

Electroanalysis of organic residues of the propellant stabiliser ethyl-centralite (1,3 diethyl-1,3 diphenyl urea, EC) generated from the discharge of a weapon or improvised explosive devices is examined. Comparative effects of an electrode modifier, nanoparticles of magnetite (Fe3O4), on the sensor performance was of interest, with customised printed prototype development and analysis of organic firearm residue (OFAR) samples. Differential pulse voltammetry (DPV) calibration studies realised sensitivity of 6.37 × 10−2 μA∙μM−1 (over the concentration range 2.5–50 μM) at the magnetic nanoparticle modified electrode, representing a 1.65 fold signal increase relative to unmodified electrodes with limit of detection 4.39 µM. Inclusion of the OFAR co-existing diphenylamine (DPA) stabiliser realised signal discrimination and sensitivity of 7.49 × 10−2 and 5.49 × 10−2 μA∙μM −1 for DPA, and EC respectively, using DPV over the same range. The work culminated in the qualitative and quantitative analysis of propellant stabilisers in firearm residue acquired from a single base shotgun shell, with recovery from a target sample cloth, together with unburnt propellant, making promising first steps towards a customised screen-printed prototype for use by forensic professionals. Scanning electron microscopy/energy dispersive spectroscopy and atomic force microscopy were employed for particle confirmatory analysis.

Cu(II) and Mo(VI) Schiff base complexes immobilized on magnetic multiwalled carbon nanotubes: Oxidation of olefins and theoretical study

In this study, magnetic multiwalled carbon nanotubes (MMWCNT@SiO2) were anchored with phenylene diamine and subsequently prepared as Schiff base through mono condensation with salicylaldehyde, resulting in MMWCNT@SiO2/Schiff base. This was then complexed with either copper acetate monohydrate or molybdenum oxide to form MMWCNT@SiO2/Schiff base/M (M=Cu, MoO2). The prepared samples were characterized with FTIR, EDS, SEM and XRD. The catalytic behavior of the prepared samples was studied in the oxidation reaction. The results revealed that MMWCNT@SiO2/Schiff base/M (M=Cu, MoO2) effectively catalyzed the oxidation reaction of α-methyl styrene leading to more than 99% conversion and selectivity of acetophenone. In addition to the experimental investigations, theoretical calculations were conducted using DFT calculations to provide further insights into the results.

Accelerated aging of tire and road wear particles by elevated temperature, artificial sunlight and mechanical stress — A laboratory study on particle properties, extractables and leachables

Tire and road wear particles (TRWP) are generated in large quantity by automobile traffic on roads but their way of degradation in the environment is largely unclear. Laboratory experiments were performed on the effect of elevated temperature (simulating 2–3 years), sunlight exposure (simulating 0.5 years) and mechanical stress on the physical properties and chemical composition of TRWP and of cryo-milled tire tread (CMTT). No significant effects were observed of the applied mechanical stress on mean properties of pristine particles. After sunlight exposure up to 40 % in mass were lost from the TRWP, likely due to the loss of mineral incrustations from their surface. The chemical composition of TRWP and CMTT was characterized by determining 27 compounds, antioxidants (phenylene diamines), vulcanization agents (benzothiazoles and guanidines) and their transformation products (TPs). Extractables of TRWP (580–850 μg/g) were dominated by TPs, namely benzothiazolesulfonic acid (BTSA). CMTT showed much higher amounts of extractables (4600 μg/g) which were dominated by parent chemicals such as N-(1,3-dimethylbutyl)-N′-phenyl-1,4-phenylenediamine (6-PPD), diphenylguanidine (DPG) and mercaptobenzothiazole (MBT). Sunlight exposure affected the amount of extractables more strongly than elevated temperature, for TRWP (−45 % vs −20 %) and CMTT (−80 % vs −25 %) and provoked a clear shift from parent compounds to their TPs. After sunlight exposure extractables of TRWP were dominated by BTSA and DPG. Sunlight exposure drastically reduced the 6-PPD amount extracted from both, TRWP and CMTT (−93 %, −98 %), while its quinone (6-PPDQ) increased by around 1 % of the 6-PPD decrease, only. For many TPs, concentration in leachates were higher than in extracts, indicating ongoing transformation of their parent compounds during leaching. These results highlight that abiotic aging of TRWP leads to strong changes in their chemical composition which affect their particle properties and are of relevance for the environmental exposure to tire-related chemicals.

Effect of metal coordination in modulating the binding interaction of an arylimidazole-derived organic chromophore with lipase

The development of reliable fluorescent probes for selectively and sensitively detecting particular analytes in biological systems, which can acid in better understanding the roles in their native contexts. Metal-complex dyes represent a family of structures that have attracted extensive attention in broad applications owing to their unique advantages, such as stable photophysical and electromagnetic properties, as well as good biocompatibility. In this work, we synthesized and characterized a fluorescent probe called THS, which untilizes diphenylamine (DPA) as a metal chelator and an arylimidazole-derived organic chromophore as a fluorescence signal reporter. A comparative assessment of responsive THS and its Zn(II) complex to lipase, an enzyme that breaks down fats, has been performed. We have evidenced the complexation of Zn(II) improved the sensing stability, signal-to-noise ratio (SNR), and selectivity of THS toward lipase. Importantly, we successfully applied the THS-Zn(II) complex to detect lipase in serum samples. This work provides an approach for fabricating simple and effective metal complex-based fluorescence probes and a promising application for the detection of biological analytes.

A Theoretical Investigation of Decorated Novel 1,2-Di(4-pyridyl)-ethylene based Dye Sensitized Solar Cells (DSSC)

Density functional theory (DFT) approaches are employed to investigate the performance of dyes and the influence of p-conjugation in dye-sensitized solar cells (DSSCs). In this investigation, five new 1,2-di(4-pyridyl)-ethylene based conjugated donor-π-acceptor organic dyes (D-π-A) exist. The spacer is a diphenylamine (DPA) group, while the diphenyl amine group serves as the component that donateselectrons in each system, the nitro/cyano group is used as an electron accepting group. An alternate methyl/ethyl group is employed as π-conjugated spacer in order to study the effect of the auxiliary donor group. Through performing DFT calculations with the B3LYP both the polarized split-valence 6-311++G (d,p) basis sets, an excitation energies, absorption spectra and emission spectra of eachmolecule were examined. The polarizable continuum model (PCM) is utilized in studying these impact for solvent. The energies at which these dyes are LUMO and HOMO, which assure the favourable impact for electron injection and these dye regeneration process. The calculation of the HOMO-LUMO gap demonstrates good agreement when compared to spectral information. The light-harvestingefficiency (LHE), electron injection free energy (ΔGinject), as well as oscillator strength (f) are computed and explained. The calculated open-circuit photovoltage values (Voc) and electron coupling constant (VRP) for the studied dye-sensitizers are also included in this study.

2D/2D heterostructure Ni-Fe LDH/black phosphorus nanosheets with AuNP for noxious substance diphenylamine detection in food samples

In this study, gold nanoparticles decorated on nickel–iron layered double hydroxide with black phosphorus nanosheets (AuNP/Ni-Fe LDH/BPNSs) composite were prepared using a stirring method. Analyte tracing is required for developing viable sensors. The AuNP/Ni-Fe LDH/BPNSs composite exhibited a large specific surface area, high conductivity, high electrocatalytic activity, and rapid electron transfer. These properties play a vital role in monitoring diphenylamine (DPA) in food samples. The formation of the AuNP/Ni-Fe LDH/BPNSs composite was confirmed using various structural and morphological characterization techniques. The electroanalytical character of the AuNP/Ni-Fe LDH/BPNSs composite was evaluated using voltammetry. Interestingly, the AuNP/Ni-Fe LDH/BPNSs showed a wide linear range of 0.0125–1003.82 μM and a detection limit of 4.63 nM with a sensitivity of 0.399 µA µM−1 cm−2. The constructed sensor shows considerable selectivity, stability, repeatability, and reproducibility, and the practicability of DPA was monitored in the apples, sweet tomatoes, pears, and grapes with satisfactory recoveries.

Tunable transparent terahertz absorber for sensing and radiation warming

The lack in efficient functional devices has hindered plenty practical applications in terahertz (THz) band. In this work, we developed transparent THz absorber by employing trilayer Salisbury screen structure. Monolayer graphene and indium tin oxide (ITO) glass were spaced by a thin dielectric film, forming a transparent THz absorber. Assisted by ion gel, the carrier density of graphene layer can be effectively tuned through small external electrical gating (−2.5 V-2.5 V), with a modulation depth reaching to 100%. Taking advantage of the strong π−π interaction between graphene and external molecules containing π electrons, our fabricated transparent THz absorber enabled diphenylamine (DPA) detection. The adsorbed DPA molecule moves Fermi level of graphene toward Dirac point, performing a limit of detection of 5.5 ng. Moreover, by transferring the absorbed radiation into heat, our fabricated absorber can serve as a radiation warming device. The surface temperature of transparent THz absorber is 0.7 °C higher than that of glass in IR radiation environment. Note that the absorber is highly transparent in visible band, it will not prevent photosynthesis process of plants. Thereby, the THz absorbers have potential practical applications in diverse fields including wave manipulation, molecule sensing, and radiation warming.

Design, Synthesis and Characterization of Palladium-Functionalized Covalent Organic Framework and Its Application as Heterogeneous Catalysis for C-H Arylation of Azoles.

A novel triazine-based covalent organic framework (TFPT-Bz COF) has been constructed by the condensation of 2,4,6-tris(5-formyl-2-pyridinoxy)-1,3,5-triazine (TFPT) and benzidine (BZ) with deep eutectic solvent (DES) as the reaction medium. After the introduction of Pd ions through strong coordination to TFPT-Bz COF matrix, the constructed TFPT-Bz COF/Pd composite exhibited excellent catalytic activity for C-H arylation of azoles with aryl halides in 2-methyltetrahydrofuran. The protocol allows the arylation of a variety of substituted azoles with diverse aryl halides in high to excellent yield. Moreover, the TFPT-Bz COF/Pd catalyst can be recycled several times without significantly reducing its activity.

New insights on the photocomplex of Roseiflexus castenholzii revealed from comparisons of native and carotenoid-depleted complexes

In wild-type phototrophic organisms, carotenoids (Crts) are primarily packed into specific pigment-protein complexes along with (Bacterio)chlorophylls and play important roles in the photosynthesis. Diphenylamine (DPA) inhibits carotenogenesis but not phototrophic growth of anoxygenic phototrophs and eliminates virtually all Crts from photocomplexes. To investigate the effect of Crts on assembly of the reaction center-light-harvesting (RC-LH) complex from the filamentous anoxygenic phototroph Roseiflexus (Rfl.) castenholzii, we generated carotenoidless (Crt-less) RC-LH complexes by growing cells in the presence of DPA. Here, we present cryo-EM structures of the Rfl. castenholzii native and Crt-less RC-LH complexes with resolutions of 2.86Å and 2.85Å, respectively. From the high-quality map obtained, several important but previously unresolved details in the Rfl. castenholzii RC-LH structure were determined unambiguously including the assignment and likely function of three small polypeptides, and the content and spatial arrangement of Crts with bacteriochlorophyll molecules. The overall structures of Crt-containing and Crt-less complexes are similar. However, structural comparisons showed that only five Crts remain in complexes from DPA-treated cells and that the subunit X (TMx) flanked on the N-terminal helix of the Cyt-subunit is missing. Based on these results, the function of Crts in the assembly of the Rfl. castenholzii RC-LH complex and the molecular mechanism of quinone exchange is discussed. These structural details provide a fresh look at the photosynthetic apparatus of an evolutionary ancient phototroph as well as new insights into the importance of Crts for proper assembly and functioning of the RC-LH complex.

Preparation, characterization, and spectroscopic properties of a novel iron (III), copper (II), and nickel (II) complexes with Schiff base ligand derived from salicylaldehyde and p–phenylene diamine on Polyvinyl chloride photodegradation

Preparation, characterization, and spectroscopic properties of a novel iron (III), copper (II), and nickel (II) complexes with Schiff base ligand derived from salicylaldehyde and p–phenylene diamine on Polyvinyl chloride photodegradation

Phyto-squalane: A new active ingredient to prevent superficial scald on pears

Superficial scald (SS) is a detrimental postharvest physiological disorder on apples and pears during mid and long-term cold storage. Since diphenylamine (DPA) and ethoxyquin were banned from European markets, there has been an active search for new chemical alternatives. Different phyto-squalane (PSQ-E) treatments (0.1–4.0% w/v) applied at harvest were evaluated in pears from different growing areas and harvest maturity during four consecutive seasons. Fruit quality (external appearance, firmness, soluble solids, ethylene production), SS development, and biomarkers for SS (α-farnesene, CTols) were evaluated at different times during cold storage (up to 210 d, −0.5 to 0.5 °C, > 90%RH). In general, PSQ-E emulsions (0.1–4.0% w/v) applied at harvest were able to significantly reduce or completely prevent SS development in pears from different growing areas, seasons, and maturity levels at harvest. Treated fruit had reduced levels of conjugated trienes (TC281, TC269), but not α-farnesene content. PSQ-E treatments reduced fruit softening, de-greening, and ethylene production compared to the untreated control (UTC) or DPA. Phyto-squalane is a novel new active ingredient that could replace current crop protectants, such as diphenylamine and ethoxyquin, to control superficial scald on pears.

Study on Synthesis and Performance of Methyl Diphenyl Urea Stabilizer

Diphenylamine (DPA), formyl chloride, and sodium hydride (NaH) as raw materials synthesize methyldiphenylurea stabilizer by alkylation reaction. The physical and chemical properties of methyldiphenylurea were characterized by nuclear magnetic resonance hydrogen spectrum (1HNMR), X-ray energy spectrum (EDS), Fourier transforms infrared spectroscopy (FT-IR) and differential thermal analysis (DTA). Thermal Decomposition Experiment of Nitrate Propellant Containing Stabilizer by Thermogravimetric Analysis (TGA), exploring the Effect of Different Stabilizers. The molecular surface electrostatic potential energy of methyl diphenyl urea, triphenylamine ( TPA ), dimethyl diphenyl urea (C2), and glycerol trinitrate were calculated by Materials Studio software. The interaction between the stabilizer and glycerol trinitrate molecule was studied. The results showed that the weight loss rate of methyl diphenyl urea was less than 0.1 % within 30 days, and the chemical stability was good. And its negative electrostatic potential energy is larger than that of C2 and TPA, its intermolecular binding ability with glycerol trinitrate is stronger, and its inhibition of nitrate decomposition stability is the best.

Boosting electrochemical property of carbon cloth for supercapacitors with electrodeposited aniline-based copolymers

As a kind of promising electrode in flexible supercapacitors, carbon cloth (CC) has been functionalized to boost its electrochemical performance. Here, facile electrochemical copolymerization was used to boost the electrochemical property of CC by adjusting the structure and morphology of electrodeposited aniline-based copolymers. With the optimized feeding ratio of triphenylamine (TPA), the aniline-based copolymer (PANI-T) was obtained on the functionalized CC (FCC) with a unique morphology as network of nanowires, showing the higher areal specific capacitance of 2489 mF cm−2 than the one with polyaniline (PANI) nanorods (FCC@PANI) of 2125 mF cm−2 and the one with copolymer nanoparticles of aniline and diphenylamine (DPA) (FCC@PANI-D) of 1693 mF cm−2 at 1 mA cm−2. Compared with the FCC@PANI electrode, the boosting ratio was 126% and 147% for the FCC@PANI-D and FCC@PANI-T, respectively. The electrochemical performance of the flexible solid-state symmetrical supercapacitor (FSSC) indicated the promising potential of the FCC@PANI-T for practical application.

Chiral covalent organic framework-based open tubular capillary electrochromatography column for enantioseparation of selected amino acids and pesticides.

A novel chiral covalent organic framework (CCOF) was synthesized with an imine covalent organic framework TpBD (synthesized via Schiff-base reaction between phloroglucinol (Tp) and benzidine (BD)) modified using (1S)-(+)-10-camphorsulfonyl chloride as chiral ligand by chemical bonding method for the first time, and was characterized by X-ray diffraction, Fourier-transform infrared spectra, X-ray photoelectron spectroscopy, nitrogen adsorption/desorption, thermogravimetry analysis, and zeta-potential. The results revealed that the CCOF had good crystallinity, high specific surface area and good thermal stability. Then, the CCOF was employed as stationary phase in open-tubular capillary electrochromatography (OT-CEC) column (the CCOF-bonded OT-CEC column) for enantioseparation of 21 single chiral compounds (12 natural amino acids including acidic, neutral and basic, 9 pesticides including herbicides, insecticides and fungicides) and simultaneous enantioseparation of mixture amino acids and pesticides with similar structures or properties. Under the optimized CEC conditions, all the analytes reached the baseline separation with high resolutions of 1.67-25.93 and selectivity factors of 1.06-3.49 in 8min. Finally, the reproducibility and stability of the CCOF-bonded OT-CEC column were measured. Relative standard deviations (RSDs) of retention time and separation efficiency were 0.58-4.57% and 1.85-4.98%, and not obviously changed after 150 runs. These results demonstrate that COFs-modified OT-CEC explore a promising method to separate chiral compounds.