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Wastewater pollution is a pressing environmental issue, necessitating effective remediation strategies to mitigate its impact. This study investigates the use of an efficient catalyst for degrading nitrophenols by converting them into useful aromatic amines, which are crucial building blocks for many pharma industries, and photodegradation of various dyes in their unitary solution as well as in mixture. The Cu-Co-Mn ferrite was synthesized using the sol-gel process and sintered at different temperatures. Structural analysis using XRD and Rietveld refinement revealed a crystal structure corresponding to the Fd 3 ‾ m space group having high purity in all the samples. Additionally, the impact of sintering temperature on the magnetic features of the phases were also studied and the findings suggest that all the phases exhibit ferromagnetic behaviour, which means they can be easily separated from reaction mixtures using an external magnetic field. It was also found that higher sintering temperatures lead to a rise in saturation magnetization and magnetic moment with decrease in coercivity (H c). Further, it was observed that Curie temperature (T c) increases with increase in sintering temperature with the exception of CFM400. The catalytic performance of all the catalysts, including CFM400, CFM500, CFM600, CFM800, and CFM1000, was evaluated and the results indicate that CFM400 exhibits the highest catalytic activity for nitrophenols reduction and photodegradation of dyes, which could be accredited to its larger BET surface area and lower PL intensity. Overall, the structural and magnetic features of the catalyst's sheds light on the underlying mechanisms governing their catalytic activity. These insights offer valuable guidance in the designing and development of effective catalysts for sustainable wastewater treatment practices, emphasizing the importance of considering both structural and magnetic features in catalyst design. [ABSTRACT FROM AUTHOR]

Drawing on prior reports highlighting the redox mediator properties of powdered activated carbon (PAC), this study was designed to evaluate these properties to enhance the decolorization of azo dye by Klebsiella quasipneumoniae GT7. It was found that the presence of 0.5 % PAC in the medium increased the biodecolorization rate early in incubation. Chemical analysis revealed that dye conversion into aromatic amines occurred in microbial systems both with and without PAC. However, at initial dye concentrations (C id) of 2 mM or higher, some dye remained on the PAC surface and in the medium. In contrast, the PAC-free system achieved nearly 100 % biodecolorization at all initial dye concentrations. The negative impact of PAC on decolorization efficiency in microbial systems with high initial dye concentrations cannot be solely explained by its redox mediator function. This study used the amphoteric-Donnan model for PAC's electrical double layer (EDL) and Mitchell's chemiosmotic model for bacterial proton motive force (PMF) to explore this. It found that charge storage in PAC's EDL regulates electron transfer fluxes, and proton species enhance the proton motive force across the bacterial membrane. These observations improve the understanding of PAC's role in microbial decolorization and its potential future applications. [Display omitted] • Dye biodegradation occurs mainly on activated carbon's porous surface in the medium. • Activated carbon enhances biodecolorization at low initial dye concentrations. • At high initial dye levels, activated carbon reduces final biodecolorization yield. • Charge storage in carbon's electrical double layer controls electron transfer flux. • Proton storage on carbon boosts proton motive force across the bacterial membrane. [ABSTRACT FROM AUTHOR]

Intercalation chemistry is pivotal in discovering the dimension-dependent properties of 2D materials and expanding their applications. Layered bismuth oxide with composition Bi 0.775 Ln 0.225 O 1.5 (Ln = La, Pr, Nd, Sm, and Eu) has been demonstrated to intercalate both aliphatic and aromatic amines, resulting in the unit cell expansion along the c -axis. Aliphatic amines were present in a vertical orientation, whereas aromatic amines preferred a horizontal orientation. The intercalated amine concentrations ranged from 0.15 to 0.54 mole per mole of the host. Among the chosen amines, ethylenediamine intercalation enhanced the c -axis of Bi 0.775 Pr 0.225 O 1.5 by 20 Å, justified by the high amounts of intercalant and intermolecular hydrogen bonding between them, resulting in a bilayer arrangement. The lamellar-plate-like morphology filled with intercalants and twinning collapse was noticed in the FESEM and SAED patterns after the intercalation process. The ethylenediamine intercalated Bi 0.775 Pr 0.225 O 1.5 was further evaluated for iodine adsorption from non-aqueous solutions through chemisorption following pseudo-second-order kinetics. The X-ray diffraction peaks after adsorption suggested bilayer to monolayer transformation aided by chemical alterations within the host's van der Waals gaps. The N–I vibration mode, observed in the FTIR spectrum of the iodine-adsorbed sample, further augmented the interaction between the two during adsorption. [ABSTRACT FROM AUTHOR]

Waterpipe smoking is increasingly popular and understanding how chemicals found in hookah smoke may be harmful to human bronchial epithelial cells is of great importance. 4,4'-Oxydianiline (ODA), is an aromatic amine which is present at comparatively high levels in hookah smoke. The metabolism and the subsequent toxicity of ODA in human bronchial epithelial cells remains unknown. Given that ODA is an aromatic amine, we hypothesized that ODA is N -acetylated and induces DNA damage following exposure to immortalized human bronchial epithelial cells (BEP2D cells). We measured the N -acetylation of ODA to mono-acetyl-ODA and the N -acetylation of mono-acetyl-ODA to diacetyl-ODA by BEP2D cells following separation and quantitation by high performance liquid chromatography. For ODA, the apparent K M in cells was 12.4 ± 3.7 µM with a V max of 0.69 ± 0.03 nmol/min/106 cells, while for mono-acetyl-ODA, the apparent K M was 111.2 ± 48.3 µM with a V max of 17.8 ± 5.7 nmol/min/106 cells ODA exposure for 24 h resulted in DNA damage to BEP2D cells following concentrations as low as 0.1 µM as measured by yH2Ax protein expression These results demonstrate that ODA, the most prevalent aromatic amine identified in hookah smoke, is N -acetylated and induces DNA damage in human bronchial epithelial cells. • 4,4'-Oxydianiline (ODA) is present at comparatively high levels in hookah smoke. • N -acetylation of ODA was determined in human bronchial epithelial cells. • ODA exposure resulted in DNA damage to human bronchial epithelial cells. [ABSTRACT FROM AUTHOR]

Paraburkholderia terrae strain KU-15 grows on 2- and 4-nitrobenzoate and 2- and 4-aminobenzoate (ABA) as the sole nitrogen and carbon sources. The genes responsible for the potential degradation of 2- and 4-nitrobenzoate and 2-ABA have been predicted from its genome sequence. In this study, we identified the pab operon in P. terrae strain KU-15. This operon is responsible for the 4-ABA degradation pathway, which involves the formation of a γ-glutamylated intermediate. Reverse transcription–polymerase chain reaction revealed that the pab operon was induced by 4-ABA. Herein, studying the deletion of pabA and pabB1 in strain KU-15 and the examining of Escherichia coli expressing the pab operon revealed the involvement of the operon in 4-ABA degradation. The first step of the degradation pathway is the formation of a γ-glutamylated intermediate, whereby 4-ABA is converted to γ-glutamyl-4-carboxyanilide (γ-GCA). Subsequently, γ-GCA is oxidized to protocatechuate. Overexpression of various genes in E. coli and purification of recombinant proteins permitted the functional characterization of relevant pathway proteins: PabA is a γ-GCA synthetase, PabB1-B3 functions in a multicomponent dioxygenase system responsible for γ-GCA dioxygenation, and PabC is a γ-GCA hydrolase that reverses the formation of γ-GCA by PabA. [ABSTRACT FROM AUTHOR]

Heterocyclic amines (HCAs) are mutagenic compounds found in cooked meat. Recent epidemiological studies reported significant associations between dietary HCA exposure and insulin resistance and type II diabetes, and we recently reported that HCAs induce insulin resistance and glucose production in human hepatocytes. It is well known that HCAs require hepatic bioactivation by cytochrome P450 1A2 (CYP1A2) and N -acetyltransferase 2 (NAT2). NAT2 expresses a well-defined genetic polymorphism in humans that, depending on the combination of NAT2 alleles, correlates to rapid, intermediate, or slow acetylator phenotype that exhibits differential metabolism of aromatic amines and HCAs. No previous studies have examined the role of NAT2 genetic polymorphism in the context of HCA-mediated induction of glucose production. In the present study, we assessed the effect of three HCAs commonly found in cooked meat (2-amino-3,4-dimethylimidazo[4,5- f ]quinoline [MeIQ], 2-amino-3,8-dimethylimidazo[4,5- f ]quinoxaline [MeIQx], and 2-amino-1-methyl-6-phenylimidazo[4,5- b ]pyridine [PhIP]) on glucose production in cryopreserved human hepatocytes with slow, intermediate, or rapid NAT2 acetylator phenotype. HCA treatment did not affect glucose production in slow NAT2 acetylator hepatocytes, while a slight increase in glucose production was observed in intermediate NAT2 acetylators treated with MeIQ or MeIQx. However, significant increases in glucose production were observed in rapid NAT2 acetylators following each HCA. The current findings suggest that individuals who are rapid NAT2 acetylators may be at a greater risk of developing hyperglycemia and insulin resistance following dietary exposure to HCAs. [Display omitted] • HCAs promote insulin resistance and glucose production in human hepatocytes. • HCA-induced glucose production required N -acetyltransferase 2 (NAT2) metabolism. • Rapid NAT2 acetylators may be more susceptible to the metabolic effect of HCAs. [ABSTRACT FROM AUTHOR]

[Display omitted] Reaction between tetracyanoethylene and N,N -dimethyl-or N -(2-pyridyl)hydrazines affords 5-amino-3,4-dicyano-pyrazoles. In cases of aromatic amines, replacement of one cyano group by amino one occurs thus giving N -(tricyano-vinyl)anilines. [ABSTRACT FROM AUTHOR]

Occasionally, our group found that the degradation of tetracycline by ferrate(VI) could be promoted by four co-exist contaminants, containing aromatic amines (ofloxacin, diatrizoic acid, sulfadiazine and alachlor). This study investigated the promotion of aromatic amine groups on tetracycline degradation by ferrate(VI) by using aniline as a model compound. The results implied that the presence of aniline increased the degradation rate of tetracycline by 2.76 times, and the enhancement was weakened gradually with the decrease of pH from 10 to 7.5. The generation of Fe(IV) and·OH by the reaction between ferrate(VI) and aniline was proposed to enhance the degradation of tetracycline, supported by quenching experiments, electron paramagnetic resonance (EPR) and theoretical calculations. A positive correlation was found between the rate constant of tetracycline degradation and the electron-donating ability of the substituted amines (quantified by the Hammett substituent constants). In addition, the degradation of tetracycline was remarkably inhibited by HA and some inorganic ions such as NO 3 -, SO 4 2-, Cl-, Ca2+, and Mg2+, and the inhibition also happened in the Songhua River water and the secondary effluent. The present study provided an insight into the complex oxidation process for the degradation of micropollutants containing aromatic amine by ferrate in water treatment. [Display omitted] • Aniline promoted tetracycline degradation by Fe(VI). • k obs is positively correlated with electron-donating ability of substituted anilines. • Fe(IV) and·OH were the main active species to promote tetracycline degradation. • Inorganic ions and HA could inhibit the promotion of tetracycline degradation. • The promotion becomes increasingly significant with the increase of pH. [ABSTRACT FROM AUTHOR]

Despite its significance for applications related to plant growth, the development of carbon dots (CDs) with bright red emissions still faces multiple obstacles. Herein, red emission hydrophobic carbon dots (RH-CDs) featuring one emission peak centered at 594 nm and a shoulder emission peak at 630 nm with a quantum yield of 34 % and a wide full width at half maximum (FWHM) of 100 nm (580 nm–680 nm) were synthesized by adopting large conjugated perylene anhydride and aromatic amine precursors under solvothermal conditions. Density functional theory calculations support the method of using larger conjugated systems and higher graphite N doping to increase red emissions from CDs. With a post-surface functionalization strategy, polyvinylpyrrolidone (PVP)-modified RH-CDs (QY = 12 %) were utilized as an anti-counterfeiting ink for information printing. Moreover, both blue-red light-emitting diodes (LEDs) and light conversion poly (methyl methacrylate) (PMMA)-CDs film were fabricated with emission spectra that are consistent with the absorption spectra of plants, suggesting that the prepared RH-CDs may have widespread application potential as a stable fluorescent material in plant growth. [Display omitted] [ABSTRACT FROM AUTHOR]

• Synthesis of Cu(I)/Fe(II) heterobimetallic complexes. • Quasireversible redox behaviour is observed for all heterobimetallic complexes. • Complexes exhibit red emission in dichloromethane solution. • Complex 4 worked as effective catalyst for C-N coupling reaction. A new series of heterobimetallic complexes of the type [Cu(L)(PPh 3) 2 ]X (1–4) [where L = trans-4-(ferrocenylideneamino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one; PPh 3 = triphenylphosphine, X = NO 3 −(1), ClO 4 − (2), BF 4 − (3) , PF 6 − (4)] were prepared by reaction of L with [Cu(MeCN) 2 (PPh 3) 2 ]X and characterized by elemental analysis, FTIR, 1H NMR, 31P NMR and UV–visible spectral studies. The thermal stability of (1–4) has been investigated by using thermogravimetric analysis (TGA). X-ray powder diffraction of the representative complex 1 used to clarify the crystal structure of the complex. The electrochemical behaviour of complexes (1–4) displayed quasireversible redox behaviour corresponding to Cu(I)/Cu(II) and Fe(II)/Fe(III) couples. All complexes show red emission as a result of ligand-ligand charge transfer (LLCT) and metal-ligand charge transfer (MLCT) or admixture of them. The catalytic efficiency of the complexes (1–4) was tested and it was found that the complex 4 worked as an effective catalyst for the C-N coupling reaction of aromatic amines and aryl halides. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Drying was observed jointly gravimetrically and thermomechanically. • The diffusion coefficient increased with increasing cross-link density of the epoxy resin. • CLTE, heat capacity and CME decreased with increasing cross-link density. • The most significant dependence of the diffusion coefficient was observed with CME. Today epoxy novolac resins are of great interest for the aerospace industry. Thermal properties of the polymer matrix, as well as the effect of moisture on the characteristics of polymer composite materials (PCM) under thermomechanical impacts, are critical tasks in creating dimensionally stable structures operating in a wide temperature range. Particularly, thermal and moisture expansion as well as heat capacity are important parameters for evaluating of polymer matrices and modeling their properties. In this work, polymers based on a number of epoxy novolac resins with aromatic amine hardener were studied. The values of the crosslink density were experimentally determined, and a comparative analysis of thermal expansion and heat capacity for epoxy polymers with different crosslink density was carried out. The dependence of thermophysical properties on polymer crosslinking density is shown, both in glass and highly elastic states. Additionally, this study analyzes the process of water sorption by polymers and the coefficient of moisture expansion. The most significant dependence of the diffusion coefficient was observed with coefficient of moisture expansion. [ABSTRACT FROM AUTHOR]

Aromatic amines, the common organic metabolites of chemical raw materials and herbicides, has attracted wide attention due to its difficult degradation and carcinogenic risk. This study aims to use microbial co-metabolism technology to efficiently degrade p-chloroaniline (PCA), which is a highly toxic aromatic amine. From the perspective of enzyme substrate specificity, a system for efficient degradation of PCA using aniline as a co-substrate was constructed. The degradation conditions were optimized by response surface methodology, and the degradation efficiency of PCA was 81.12 % (50 mg/L). Further, the co-metabolism mechanism was clarified by multiple methods. Enzyme activity assay preliminarily showed that aniline induced catechol 2,3-dioxygenase activity. Then the intermediates of PCA and aniline degradation was identified and two possible PCA degradation pathways were proposed. Transcriptomic analyzed the molecular mechanism of aniline-enhanced PCA degradation: Nitrogen utilization efficiency was accelerated by up-regulation of nitrogen metabolism-related genes. Several oxidoreductases including catechol 2,3-dioxygenase were significantly up-regulated. TCA cycle and ATP synthesis were accelerated, facilitating cell metabolism and energy supply. The work contributes a worthy theory for the remediation of PCA-aniline co-contaminated sites. [Display omitted] • Biodegradation of p-Chloroaniline was performed by co-metabolism with aniline. • Aniline activated the catechol 2,3-dioxygenase activity of strain CA-1. • p-Chloroaniline was degraded simultaneously by meta- and ortho-cleavage pathways. • Co-metabolism stimulated the genes encoding N metabolism, oxygenase and TCA cycle. [ABSTRACT FROM AUTHOR]

Heterocyclic aromatic amines (HAAs) and advanced glycation end products (AGEs) are hazardous substances produced when food is heated. In this study, the ability of plasma-activated water (PAW) to simultaneously mitigate production of HAAs and AGEs in roasted beef patties was investigated. Assays of free radicals, lipid peroxidation, and active carbonyls were used to analyze the mechanisms. PAW treatment decreased the contents of free HAAs, free AGEs, bound HAAs, and bound AGEs to 12.65 ng/g, 0.10 μg/g, 297.74 ng/g, and 4.32 μg/g, with the inhibition rates of 23.88%, 23.08%, 11.02%, and 8.47%, respectively. PAW treatment decreased HAAs and AGEs and mitigated their increase during storage. The decrease of HAAs and AGEs in PAW-treated samples was correlated with the enhancement of antioxidant capacity. The increase of free radical scavenging ability by PAW treatment led to the decrease of lipid peroxidation and the decrease of active carbonyls, HAAs, and AGEs in meat products. [Display omitted] • Plasma-activated water (PAW) treatment inhibited the formation of HAAs and AGEs. • PAW treatment reached peak inhibition rates of 23.88% for HAAs and 23.08% for AGEs. • The mitigative capacity on HAAs and AGEs results from scavenging free radicals. • PAW treatment led to the decrease of lipid peroxidation and active carbonyls. [ABSTRACT FROM AUTHOR]

• Nanocomposite, conducting polymer characteristics , and various synthesis approaches of polyaniline presented along with their merits and demerits. • Use of PANI in water remediation via different methods is discussed. • Various synthesis routes and procedures of PANI nanocomposites are shown. • Type-II, p-n, Z-scheme, and S-scheme heterojunction structures of PANI with numerous photocatalysts in binary nanocomposites are discussed. • Photocatalytic implications of PANI binary nanocomposite photocatalysts with various semiconducting materials are presented. • Photocatalytic mechanisms of PANI binary nanocomposites for ROS generation also included. Composites are multiphasic materials that show improved characteristics compared to the consisting components. In nanocomposites, the sizes of components fall in the nano dimension due to which they exhibit extraordinary features compared to normal composites and are explored in numerous areas efficiently. Polyaniline (PANI) is a fascinating conducting polymer (CP) that is extensively utilized in various fields including water remediation and generation of composites of various semiconductor photocatalysts for improvement of photocatalytic efficiency, stability, recovery and recyclability, and reduction of agglomeration and photoinduced dissolution in solution due to extensive delocalized pi-electron system, effective mobility of electrons, lower band gap, and presence of aromatic amine functionalities in the polymer backbone. PANI forms binary and multi-component nanocomposites with photocatalysts such as metal-based (metal, metal oxide, metal sulfide, metal halide, metal ferrites, etc.), and carbon-based (GO, rGO, g-C 3 N 4 , CNT) which exhibit highly improve photocatalytic performance compared to pristine semiconductor photocatalysts against numerous water pollutants. Usually, PANI in the binary nanocomposites with the metal- and carbon-based semiconductor photocatalysts generates heterojunction structures of type-II, p-n, Z-scheme, and S-scheme and reduces band gap, enhances optical absorbance in visible light, increases separation of charge carriers, and their delocalization and via this prevent charge carriers recombination and their life span due to which photocatalytic performance is amplified. This review study is planned to present a review on PANI based binary nanocomposite photocatalysts, their synthesis, features, and photocatalytic applications for degradation of organic pollutants (dyes, phenolic pollutants, nitroaromatics, pesticide, pharmaceuticals pesticides, etc.) and inorganic pollutants under visible, UV, and solar light exposure at numerous reaction conditions. Moreover, this study highlighted various synthesis procedures of polyaniline and their merits, and demerits, synthesis routes of polyaniline nanocomposites. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel approach for seven-membered benzazepinone core of tolvaptan. • First report on the synthesis of tolvaptan by haloamine cyclization. • Inexpensive starting materials. • Concise synthesis of benzazepinone. • Improved yield of (S)-tolvaptan. A novel and concise approach has been developed for the total synthesis of (S) - tolvaptan, which is used for the treatment of hyponatremia. The key intermediate, benzazepinone has been synthesized in three steps through ortho -acylation of N -Pivalamide protected aryl amine followed by an intramolecular haloamine cyclization. The total synthesis of (S) - tolvaptan from p -chloroaniline has been accomplished in seven steps with 43% overall yield. [ABSTRACT FROM AUTHOR]

The strong excitonic effect is widely prevalent in covalent organic frameworks (COFs)-based catalysts, while the high exciton binding energies (E b) of COFs seriously limit their photocatalytic performance. Herein, theoretical calculations are conducted to evaluate the E b values of potential COFs derived from benzo[1,2-b:3,4-b'-b'']trithiophene-2,5,8-tricarbaldehyde (BTT) and 2,4,6-trihydroxybenzene-1,3,5-tricarbaldehyde (Bp) as aldehyde monomers. Diverse aromatic amine linkers including dipyridine diamine (BPy), biphenyl diamine (BPh), and p -phenylenediamine (MPh) with different molecular lengths and N-sites are used as linker models to regulate the excitonic effect. The obtained BTT-BPy-COF with a long BPy linker and the lowest calculated E b value possesses the best photocatalytic performance for benzylamine coupling, with conversion and selectivity up to 99% accompanied by a high oxidation rate, outperforming most of the reported works. Further mechanistic investigation reveals that the bipyridine-N sites in BTT-BPy-COF exhibit strong electron transfer as well as enhanced O 2 adsorption and activation that is beneficial to photocatalytic benzylamine coupling. [Display omitted] • Different aromatic amine linkers are used to regulate the excitonic effect of COFs. • Photocatalytic performance of the obtained COFs closely relates to their E b values. • BTT-BPy-COF with low E b value and pyridine-N linker shows best catalytic activity. [ABSTRACT FROM AUTHOR]

In this study, a novel technique utilizing vortex-assisted dispersive liquid-liquid microextraction with magnetic deep eutectic solvents (MDESs) was established and coupled with HPLC-UV to analyze six primary aromatic amines (PAAs). A novel hydrophobic MDES prepared from trioctylphosphine oxide, octanol, and CoCl 2 was used as the extractant, which could be dispersed uniformly during extraction, then floated onto the sample surface and re-aggregated into a single drop spontaneously after the extraction. The variables influencing the efficiency of the extraction process were investigated. When performing under the optimal extraction conditions, this method exhibited excellent linearity, low limits of detection (0.2–0.9 ng mL−1), and high precision (RSD ≤ 8.3 %). The enrichment factors ranged from 56 to 182. Satisfactory recoveries in the range of 91.6–109.2 % with RSDs < 7.1 % were obtained from three apple juices and three environmental water samples. The greenness and practicality of the developed method were assessed by AGREE, AGREEprep, and blue applicability grade index metric tools. Overall, the established procedure demonstrated its simplicity, speediness, environmental friendliness, and effectiveness in analyzing PAAs from aqueous matrices. [Display omitted] • A series of hydrophobic magnetic deep eutectic solvents (HMDESs) were synthesized. • The physicochemical and thermal properties of synthesized HMDESs were characterized. • A vortex-assisted HMDES-based DLLME method was developed. • The proposed method is simple, fast, robust, cost-effective, eco-friendly and highly sensitive. • This method realizes simultaneous pre-concentration of 6 primary aromatic amines from juice and water matrices. [ABSTRACT FROM AUTHOR]

[Display omitted] Photoredox catalysis has become an indispensable solution for the synthesis of small organic molecules. However, the precise construction of single-atomic active sites not only determines the catalytic performance, but also avails the understanding of structure–activity relationship. Herein, we develop a facile approach to immobilize single-atom Ni sites anchored porous covalent organic framework (COF) by use of 4,4′,4″-(1,3,5-triazine-2,4,6-triyl)trianiline and 2,6-diformylpyridine (Ni SAS/TD-COF). Ni SAS/TD-COF catalyst achieves excellent catalytic performance in visible-light-driven catalytic carbon–nitrogen cross-coupling reaction between aryl bromides and amines under mild conditions. The reaction provides amine products in excellent yields (71%–97%) with a wide range of substrates, including aryl and heteroaryl bromides with electron-deficient, electron-rich and neutral groups. Notably, Ni SAS/TD-COF could be recovered from the reaction mixture, corresponding to the negligible loss of photoredox performance after several cycles. This work provides a promising opportunity upon rational design of single-atomic active sites on COFs and the fundamental insight of photoredox mechanism for sustainable organic transformation. [ABSTRACT FROM AUTHOR]

• Phenolic content and antioxidant activities of South African E. alsinoides were described for the first time. • Functional groups present in the same species were also investigated for the first time. • The content of individual phenolics was positively correlated with antioxidant activity. • FTIR analysis confirmed the presence of several functional groups in the plant extracts. • Results indicate that E. alsinoides contains promising bioactive molecules, which justify its use in folkloric medicine. Evolvulus alsinoides (L.) L. (Convolvulaceae) is a forb species that is highly valued in traditional medicine for its memory-enhancing effects, and a range of other ethnomedicinal properties. However, there are no studies on the phytochemical composition and antioxidant activities of E. alsinoides collected in South Africa. The present study was designed to investigate the phytochemical contents and antioxidant properties of aqueous and ethanolic plant extracts of E. alsinoides collected from the Limpopo Province of South Africa. The phytochemical contents were determined using spectrophotometric and colorimetric methods, while the antioxidant activities were determined using three in vitro antioxidant ([2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic) acid (ABTS), and Ferric reducing antioxidant power (FRAP)] assays. Additionally, the functional groups present in the extracts were analyzed using Fourier-transform infrared (FTIR) spectroscopy. Results revealed that the ethanolic extracts of E. alsinoides gave the highest content of total phenol (17.07 ± 2.28 mg GAE/g DW extract), total flavonoid (82. 44 ± 0.93 mg QE/g DW extract), and proanthocyanidin (32. 98 ± 2.10 mg CE/g DW extract). The total alkaloid and saponin quantification of the crude extract of E. alsinoides gave mean percentage values of 2.6 ± 0.2% and 33.7 ± 0.00%, respectively. The ethanol extract had the highest DPPH scavenging ability (IC 50 value: 0.4367 mg/mL), ABTS scavenging ability (IC 50 value: 0.099 mg/mL) and the best ferric reducing antioxidant power (138.16 ± 3. 27 mg TE/ g). The total phenolic, flavonoid, and proanthocyanidins contents positively correlated with DPPH and ABTS activities. The spectral data of FTIR analysis of E. alsinoides extracts revealed the presence of functional characteristic groups of carboxylic acids, aromatic amines, alkanes, phenols, alkynes, hydroxy, alcohols, and sulfoxide, which could contribute to the medicinal properties of this plant species. The results of the study justify the usage of E. alsinoides in folkloric medicine and can be explored further for pharmaceutical plant-based products. [ABSTRACT FROM AUTHOR]

[Display omitted] • SERS rapidly screened & LC-MS accurately quantified PAAs in 18 brands of PLA straws. • 2,4-TDA exceeded specific migration limits in 50% ethanol, raising safety concerns. • PAAs migration into 10% & 50% ethanol exceeded into 4% acetic acid in a short period. • Polymer additives including PBS & PBAT enhanced straws' heat & hydrolysis resistance. • Migration mechanism into different food simulants were comprehensively discussed. Polylactic acid (PLA) straws hold eco-friendly potential; however, residual diisocyanates used to enhance the mechanical strength can generate carcinogenic primary aromatic amines (PAAs), posing health risks. Herein, we present a rapid, comprehensive strategy to detecting PAAs in 18 brands of food-grade PLA straws and assessing their migration into diverse food simulants. Surface-enhanced Raman spectroscopy was conducted to rapidly screen straws for PAAs. Subsequently, qualitative determination of migrating PAAs into various food simulants (4 % acetic acid, 10 % ethanol, 50 % ethanol) occurred at 70 °C for 2 h using liquid chromatography-mass spectrometry. Three PAAs including 4,4′-methylenedianiline, 2,4′-methylenedianiline, and 2,4-diaminotoluene were detected in all straws. Specifically, 2,4-diaminotoluene in 50 % ethanol exceeded specific migration limit of 2 μg/kg, raising safety concerns. Notably, PAAs migration to 10 % and 50 % ethanol surpassed that to 4 % acetic acid within a short 2-hour period. Moreover, PLA straws underwent varying degrees of shape changes before and after migration. Straws with poly(butylene succinate) resisted deformation compared to those without, indicating enhanced heat resistance, while poly(butyleneadipate-co-terephthalate) improved hydrolysis resistance. Importantly, swelling study unveiled swelling effect wasn't the primary factor contributing to the increased PAAs migration in ethanol food simulant, as there was no significant disparity in swelling degrees across different food simulants. FT-IR and DSC analysis revealed higher PAAs content in 50 % ethanol were due to highly concentrated polar ethanol disrupting hydrogen bonds and van der Waal forces holding PLA molecules together. Overall, minimizing contact between PLA straws and alcoholic foods is crucial to avoid potential safety risks posed by PAAs. [ABSTRACT FROM AUTHOR]

Foodborne heterocyclic aromatic amines (HAAs) are potent mutagens and carcinogens, posing significant health risks. Existing enrichment methods for HAAs need better adsorption selectivity and capacity for daily exposure assessment. This study hypothesized that introducing carboxylic groups into magnetic covalent organic frameworks (m-COFs) would improve HAAs adsorption by providing additional binding sites. Hence, we prepared a novel magnetic adsorbent, termed as Fe 3 O 4 @DOPA-TpPa-(COOH) 2 capable of enhancing the HAAs detection through magnetic solid-phase extraction (MSPE) coupled with UPLC-MS. This sorbent demonstrated a large specific surface area (130.7 m2/g), high magnetic responsivity (21.05 emu/g), and robust stability, with an adsorption capacity (Qm[cal]: 81.82 mg/g) driven by electrostatic, LP − π/C-H − π interactions, and hydrogen bonding. Optimal MSPE conditions provided sensitive detection with a broad linear range (5–500 ng/mL), low limits of detection (0.01–7.01 ng/g), and excellent repeatability. Application to Cantonese mooncake samples showed satisfactory recoveries (62.12%–126.86%). This method offers a more accurate tool for detecting HAAs. [Display omitted] • Novel magnetic Fe3O4@COF-COOH was prepared for the enrichment of HAAs. • H-bonding, π···π and C-H/LP···π interactions contributed to host-guest bindings. • This sorbent is easily separated and regenerated. • A facile MSPE-HPLC-MS/MS method was developed for the detection of HAAs. • Method was successfully applied in the detection of Cantonese mooncakes. [ABSTRACT FROM AUTHOR]

• Thermal polymerization of melamine. • Fabrication of g-C 3 N 4 based photoactive photocatalyst. • Synthesis of selectively synthesized pharmaceutical materials. • Oxidative coupling of aryl amines. Oxidative coupling of amine derivatives to selectively synthesize pharmaceutical materials has been realized via photocatalysis. Herein we report on the fabrication and development of a graphitic carbon nitride (G) based visible light active photocatalyst (G-PTD), which is melamine converted graphitic carbon nitride(G) covalently integrated to a light harvesting perylene tetracarboxylic dianhydride (PTD) molecule. The synthesized photocatalyst has various functions in a highly active manner leading to high yield of newly generated azoaromatic compound. The current research endeavour highlights on the fabrication and utilization of a graphitic carbon nitride based photocatalyst for direct oxidative coupling of arylamines. [Display omitted] [ABSTRACT FROM AUTHOR]

Plant-derived natural extracts contain large amounts of polyphenolic compounds, presenting opportunities for chemical modification. The present study deals with the extraction of dye from Marigold (Tagetes erecta) , a widely cultivated and commercially utilised flower, using water as an extraction medium followed by its chemical modification for sustainable synthesis of yellow dye and dyeing of polyester fabric. Phytochemical analysis and FTIR spectroscopy of the natural dye extract from Marigold flowers indicated the presence of polyphenolic flavonoids. The water-extracted natural dye was subsequently chemically modified with aniline, a primary aryl amine, via diazotisation and coupling reactions to yield a semi-synthetic natural dye with a 1.2 ± 0.3 g yield. The major constituents in the marigold natural extract and the Modified Marigold Extract (MME) dye were characterised using High-Resolution Liquid Chromatography-Mass Spectrometry (LC-HRMS). The marigold water extract contained a high concentration of Gossypetin 8-Glucoside, a yellow-coloured flavonoid compound with a mass-to-charge ratio (m/z) of 480.0904. LC-HRMS analysis further confirmed the presence of a constituent (m/z 424.0485) in the MME dye, corresponding to the predicted mass of chemically modified Gossypetin 8-Glucoside. The MME dye was subsequently employed for dyeing polyester fabric, exhibiting maximum colour strength at 10 % shade under acidic condition. The dyeing performances of the MME-dyed fabrics were evaluated in terms of fastness and post-dyeing strength. This study demonstrates a unique and novel approach to develop a yellow semi-synthetic natural dye, emphasising its potential utility for polyester dyeing. [Display omitted] • Chemical modification of natural dye extract from widely cultivated marigold flower. • A novel approach for dye modification from marigold flower. • Sustainable and enhanced dyeing of polyester. • Overcoming the drawbacks of natural and synthetic dye. • Natural dyes for wider spectrum of fibres. [ABSTRACT FROM AUTHOR]

• Proposed naphthylamine microwave-assisted derivatization was fast and efficient. • Polypropylene membrane MMSPE devices are promising for aromatic amine extraction. • Obtained devices are viable low cost alternatives for aromatic amine biomonitoring. • This is the first use polypropylene membrane MMSPE devices with biological fluids. Exposure to tobacco smoke is highly correlated to the incidence of different types of cancer due to various carcinogenic compounds present in such smoke. Aromatic amines, such as 1-naphthylamine (1-NA) and 2-naphthylamine (2-NA), are produced in tobacco burning and are linked to bladder cancer. Miniaturized solid phase extraction techniques, such as microporous membrane solid phase extraction (MMSPE), have shown potential for the extraction of aromatic compounds. In this study, a bioanalytical method for the determination of 1-NA and 2-NA in human urine was developed using polypropylene microporous membranes as a sorptive phase for MMSPE. Urine samples were hydrolyzed with HCl for 1 h at 80 °C, after which pH was adjusted to 10. Ultrasound-assisted MMSPE procedure was optimized by factorial design as follows. To each sample, 750 µL of methanol was added, and ultrasound-assisted MMSPE was conducted for 1 h with four devices containing seven 2 mm polypropylene membrane segments. After extraction, the segments were transferred to 400 µL of hexane, and desorption was conducted for 30 min. Extracts were submitted to a simple and fast microwave-assisted derivatization procedure, by the addition of 10 µL of PFPA and heating at 480 W for 3 min, followed by clean-up with phosphate buffer pH 8.0 and GC–MS/MS analysis. Adequate linearity was obtained for both analytes in a range from 25 to 500 µg L −1, while the multiple reaction monitoring approach provided satisfactory selectivity and specificity. Intra-day (n = 6) and inter-day (n = 5) precision and accuracy were satisfactory, below 15 % and between 85 and 115 %, respectively. Recovery rates found were 91.9 and 58.4 % for 1-NA and 2-NA, respectively, with adequate precision. 1-NA was found in first-hand smokers' urine samples in a concentration range from 20.98 to 89.09 µg in 24 h, while it could be detected in second-hand smoker's urine samples, and 2-NA detected in all first and second-hand smokers' urine samples. The proposed method expands the applicability of low cost MMSPE devices to aromatic amines and biological fluids. [ABSTRACT FROM AUTHOR]

Heterocyclic aromatic amines (HAAs), arising as chemical derivatives during the high-temperature culinary treatment of proteinaceous comestibles, exhibit notable carcinogenic potential. In this paper, a composite aerogel (AGD-UiO-66) with high-capacity and fast adsorption of HAAs was made with anchoring defective UiO-66 (D-UiO-66) mediated by lauric acid on the backbone of cellulose nanofibers (CNF). AGD-UiO-66 with hierarchical porosity reduced the mass transfer efficiency for the adsorption of HAAs and achieved high adsorption amount (0.84–1.05 μmol/g) and fast adsorption (15 min). The isothermal adsorption model demonstrated that AGD-UiO-66 belonged to a multilayer adsorption mechanism for HAAs. Furthermore, AGD-UiO-66 was successfully used to adsorb 12 HAAs in different food (roasted beef, roasted pork, roasted salmon and marinade) with high recoveries of 94.65%–104.43%. The intrinsic potential of AGD-UiO-66 demonstrated that it could be widely applicable to the adsorption of HAAs in foods. [Display omitted] • The "defective design" solves the mass transfer hindrance of micropores in UiO-66. • Combination of MOFs with CNFs to form aerogels with perfectly hierarchical porosity. • AGD-UiO-66 can be used for the adsorptive removal of hazardous substances from food. [ABSTRACT FROM AUTHOR]

[Display omitted] • The impact of beech, oak and alder chips on precursors, HAs and PAHs were analyzed. • Differences in the chemical composition of controlled smoke were discriminated. • A wide range of intrinsic relationships were found among different substances. • Two aldehydes and two phenols may affect the formation of HAs and PAHs. The Frankfurter sausages smoked with beech, oak, and alder, respectively, were used to clarify the underlying impact of the smoke chemical composition on the levels of heterocyclic amines (HAs) and polycyclic aromatic hydrocarbons (PAHs). The result indicated that different wood types significantly affected the profiles of target substances in food matrices. The beech-smoked samples had lower contents of total free HAs (5.98–6.80 ng/g dry-weight-DW), PAH4 (3.31–3.83 ng/g DW), and PAH8 (10.0–10.8 ng/g DW), whereas the alder pyrolysis usually led to higher hazardous residues (8.26–9.19 ng/g DW of total free HAs, 4.24–6.60 ng/g DW of PAH4 and 14.1–23.3 ng/g DW of PAH8). In addition, the differences in smoke chemical composition were attributed to the different proportions of 15 key identified substances. Among them, two aldehydes (5-methyl-furfural & furfural) and two phenols (phenol & 5-hydroxymaltol) may have synergistic or competitive inhibitory effects on the formation of HAs and PAHs in smoked meat products. [ABSTRACT FROM AUTHOR]

• Facile, eco-friendly and efficient synthesis of silver nanoparticles. • Carboxymethyl cellulose: a dual role as a reducing agent and a stabilizer. • A surface-capping role of CMC explored by both physicochemical and catalytic studies. • Catalytic MO reduction: the induction time (12 min) before accelerating reaction rate. • A good reuse performance for 5 consecutive cycles. The present study reported a dual role as a reducing agent and a stabilizer of carboxymethyl cellulose (CMC), a natural origin biopolymer, for the synthesis of silver nanoparticles (AgNPs) via a chemical reduction method. The operating parameters were optimized and established involving pH, reaction time, reaction temperature, AgNO 3 molar concentration, CMC/Ag molar ratio. The formation of monodisperse AgNPs in the assistance of a CMC surface-capping agent thanks to an electrostatic stabilization effect was evidenced by ultraviolet-visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and transmission electron microscope (TEM). The aqueous solution consisting of AgNPs in roughly spherical shape with a mean particle size of 24.3 nm was stable in ambient condition at least 2 months. The role of CMC as a surface-capping agent was also explored via the catalytic hydrogenation of methyl orange (MO) towards aromatic amines in the presence of NaBH 4 at room temperature, revealing the induction period of 12 min before accelerating reaction rate in the next 18 min. At room temperature, such a catalytic hydrogenation of MO in water obeyed the pseudo first-order kinetic model with a rate constant of 0.2435 min−1 using 2.5 ppm CMC-capped AgNPs catalyst, and the reuse performance was remained in 5 consecutive cycles. To sum up, the present work shed light on a surface-capping role of carboxymethyl cellulose for the synthesis of silver nanoparticles by both physicochemical and catalytic studies. [ABSTRACT FROM AUTHOR]

Catalytic N-alkylation is a frequently employed method to synthesize secondary amines and imines, yet selectivity control remains as a challenge that normally requires specialized catalysts under harsh reaction conditions. Here we propose a light-switchable N-alkylation of amines with aromatic halides for selective synthesis of secondary amines and imines, using an amine-functionalized metal-organic framework (MIL-125-NH 2) under mild conditions. The MIL-125-NH 2 catalyst possesses Lewis acidic sites, which catalyze direct dehalogenative condensation of bromides with primary amines to produce secondary amines in the dark. Upon irradiation, the MIL-125-NH 2 reduces molecular oxygen to create oxygen radicals, converting bromides into the corresponding aldehydes to yield imines via a dehydrative coupling with amines. With appropriate acidity, rapid oxygen reduction kinetics, and optimized adsorption of aromatic bromides and generated water, the system catalyzes the conversion of a wide range of substrates, thus featuring it a promising method for applications. [Display omitted] • Controlled selective cross coupling of aniline and bromides mediated by irradiation. • Lewis acidic sites on MOF boost dehalogenative condensation to yield amines in the dark. • Irradiation of the MOF activates oxidative debromination to yield imines. • The NH 2 -MOF shows proper acidity, fast oxygen reduction rates, and optimized adsorption of reactants. • A wide substrate scope for the light switchable N-alkylation process. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ru@Beta was directly synthesized to confine Ru NPs within Beta zeolites. • Ru@Beta was highly active in the N-alkylation of amines with aromatic alcohols. • High yield/TON/TOF, stable recyclability, and broad substrate scope were obtained. • Synergy of confined Ru NPs and acid sites contributed to the high performance. • Moderate Ru − H intensity on the confined metal sites accelerated H-transfer process. Direct hydrogen transfer amination of alcohols with amines is an environmentally friendly and atom-economical route for the synthesis of N-alkylamines. Noble metal species are highly catalytic active sites, but the exorbitant price makes the urgency to boost the atom efficiency with stable recyclability. Herein, we demonstrated that encapsulation of Ru nanoparticles (NPs) within BEA zeolite through direct hydrothermal approach greatly promoted the catalytic efficiency in the N-alkylation of aromatic alcohols and amines under additive- and solvent-free conditions, resulting in the high yield (∼93 %), maximum turnover number (TON) of 12,822 and turnover frequency (TOF) of 9012 h−1, with stable recyclability and extendable substrate scope. The kinetic studies and in-situ characterizations revealed that the synergy of confined Ru NPs and adjacent acid sites of BEA zeolite significantly promoted the C–H bond activation in the rate-determining step of alcohol dehydrogenation into aldehydes. Besides, the acid sites also accelerated the condensation of aldehyde intermediates and anilines to promote the kinetic equilibrium, while the moderate strength of the Ru–H bond resulting from the confined Ru NPs is advantageous to balance the dehydrogenation and hydrogenation steps to reach the fascinating H-transfer process. [ABSTRACT FROM AUTHOR]

There is an increasing demand for advanced membranes that exhibit both high perm-selectivity and good stability in organic solvents, particularly for organic solvent nanofiltration (OSN). Traditional methods of synthesizing thin films using conventional interfacial polymerization (CIP) have been limited by the use of water-soluble monomers, which has hindered the development of high-performance membranes. To address this issue, a new method called organic-organic interfacial polymerization (OOIP) has been proposed. This method allows for the use of aromatic amines that are not water-soluble in the fabrication of ultrathin polyamide (PA) (<40 nm) thin film composite (TFC) membranes. By investigating five different organic solvents (tetrahydrofuran, acetone, N , N -dimethylformamide, N , N -dimethylacetamide, dimethyl sulfoxide) with varying water content as the organic phase for a water-insoluble benzidine monomer, two diffusion models of monomers were identified that resulted in different membrane structures and degrees of network crosslinking. The ultrathin PA membranes produced using tetrahydrofuran-H 2 O and N , N -dimethylformamide-H 2 O, along with solvent activation, demonstrated high methanol permeances of 11.4 L m−2 h−1 bar−1 and 6.0 L m−2 h−1 bar−1, respectively, while maintaining exceptional rejections of over 99.0 % for small molecules with molecular weights greater than 452 g mol−1. The OOIP method is scalable and reproducible, making it suitable for large-scale membrane production. This innovative approach shows great potential for advancing OSN technology and providing efficient and cost-effective separation solutions for various industries. [Display omitted] • Organic-organic interfacial polymerization was proposed to prepare OSN membranes. • Two diffusion models of the organic-organic interfacial polymerization were found. • The solvent-H 2 O affect the density and activation effect of PA layer. • The as-prepared PA TFC membranes exhibited high solvent permeance and stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Grafting of amines and diazonium salts is compared by using on-surface techniques. • Raman spectroscopy proves the nature of the interaction between the thin films and model substrates. • Electrografting of aryl amines does not provide higher grafting densities than aryldiazonium chemistry. Aryl amines have recently been shown to be effectively grafted with the use of Lewis bases. Hence, they have been proposed as a potential alternative to aryl diazonium salts for the covalent modification of surfaces. In this work we compare grafting efficiencies of aryl amines, such as 4-bromoaniline (4-BA), with aryl diazonium salts, such as 4-bromobenzene diazonium (4-BBD), on carbon-based surfaces, namely highly oriented pyrolytic graphite (HOPG) and graphene. The Lewis base 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) was employed to improve the grafting of 4-BA to the surfaces. The systems were studied with a range of techniques to confirm grafting of the organic molecules to the carbon surfaces, such as cyclic voltammetry, atomic force microscopy, scanning tunnelling microscopy and Raman spectroscopy. Density functional theory calculations demonstrate that the C-C bond is more favoured than the C-N bond. The grafting density of the aryldiazonium salts on graphite and graphene surfaces is much higher compared to aryl amines with or without the use of a Lewis base. Consequently, selection of the appropriate precursor for efficient covalent functionalization of a surface is required. [ABSTRACT FROM AUTHOR]

The efficient reduction of nitro compounds to their corresponding amino compounds has been a challenging task. In this study, we developed a method for the rapid reduction of aromatic nitro compounds to aromatic amines. The method uses B 2 pin 2 as the reducing agent and NaOH as the base, and the reaction can be completed in 15 min at 50 °C. A range of nitro compounds containing a variety of sensitive functional groups, such as halogen, thioether, cyano, vinyl, and heteroaryl were chemoselectively reduced to the corresponding anilines in good yields. [Display omitted] • Developed a metal-free method for the rapid reduction of aromatic nitro compounds. • The reaction can be completed at 50 °C in 15 min. • Nitroarenes with sensitive groups can converted into the corresponding anilines. [ABSTRACT FROM AUTHOR]

In this review, we highlight recent advances in the synthesis of N -aryl pyridinium salts, which have moved beyond the classical Zincke S N Ar reaction to focus on strategies reliant on C–N bond formation using an ever expanding array of reaction manifolds. This expansion to include C–N bond forming approaches, as well as enabling an unprecedented breadth of both arene and N -heterocyclic coupling partners, has led to a shift in perception of N -aryl pyrdinium salts to now serving as a platform for aryl amine synthesis. As a result, new synthetic applications of these salts have begun to emerge, both utilizing classic (nucleophilic additions, radical reactions, cycloadditions, etc) and emergent transformations such as deaminative transformations, isotopic labeling, and molecular editing. This review provides a timely synopsis of novel N -aryl pyridinium salt syntheses from the last 10 years (2013 to present). These strategies are separated into the two main classes, radical cation and non-radical cation methods. Highlights of recent transformations and applications of the resultant N -aryl pyridinium salts are also discussed to demonstrate the untapped synthetic potential of these scaffolds and highlight areas of continued interest. [Display omitted] [ABSTRACT FROM AUTHOR]

Quinolines and their derivatives bearing fluorine-containing substituents are essential structural motifs found in numerous bioactive compounds and advanced functional materials. Therefore, there is an urgent need to develop new synthetic methods for fluoroalkylated quinoline derivatives. In this study, we present a facile and efficient approach to access fluoroalkylated quinoline derivatives by using Eaton's reagent as a cost-effective, and commercially available reagent. This Combes cyclization reaction demonstrated compatibility with various arylamines bearing diverse functional groups, resulting in the synthesis of 2,4-bis(trifluoromethyl)quinolines and 2,4-bis(difluoromethyl)quinolines in moderate to high yields. Furthermore, this reaction can be conveniently carried out in a solvent-free one-pot protocol. [Display omitted] [ABSTRACT FROM AUTHOR]

Although copper-aliphatic amines have been extensively used as catalysts for the polymerization of 2,6-dimethylphenol (DMP) to poly (2,6-dimethyl-1,4-phenylene oxide) (PPO), the high polydispersity index (PDI) of PPO and high content of 3,3′,5,5′-tetramethyl-4,4'diphenoquinone (DPQ) in PPO significantly affect the physical properties of PPO. In this study, different CuBr-aromatic amines have been used as catalysts for synthesizing PPO. CuBr– N -methylbenzylamine shows a high yield of PPO (94.4 %) with the low DPQ yield (0.46 %) and PDI (1.33) in the presence of 0.1 % H 2 O, which facilitates the formation of dinuclear Cu(Ⅱ) species. In addition, the low dielectric constants (2.43 and 2.25) and low dielectric loss factors (1.07 × 10−3 and 1.29 × 10−3) of the PPO synthesized by CuBr– N -methylbenzylamine and CuBr-4-aminopyridine again indicate that aromatic amines are more appropriate for the synthesis of PPO with superior dielectric properties. Meanwhile, the high-molecular-weight PPO can be successfully redistributed to low-molecular-weight PPO by adding DMP in the presence of CuBr– N -methylbenzylamine, and the decreased T g values from 212.5 to 187.8 °C with decreasing M n values from 2.7 × 104 to 5.5 × 103 indicate the improved processability of the low-molecular-weight PPO. This study provides new insights on important roles of aromatic amines in the synthesis of PPO. [Display omitted] • Different highly efficient CuBr-aromatic amines are used as catalysts for synthesizing PPO. • PPOs synthesized by CuBr-aromatic amines show high thermal stability and satisfactory dielectric properties. • The molecular weight of PPO is mediated under mild conditions. [ABSTRACT FROM AUTHOR]

• A magnetic Fe 3 O 4 @LABSA-LDH@ZIF-8 nanocomposites were synthesized for the first time. • The Fe 3 O 4 @LABSA-LDH@ZIF-8 has a strong affinity for HAAs. • Fe 3 O 4 @LABSA-LDH@ZIF-8 has excellent adsorption property for HAAs in food substrates. • The current MSPE-HPLC-MS/MS was sensitive, accurate, and practical for detecting HAAs. In this research, a novel magnetic nanocomposite (Fe 3 O 4 @Zn/Al-LABSA-LDH/ZIF-8) was synthesized using Fe 3 O 4 as the magnetic core, layered double hydroxide (LDH) with linear alkylbenzene sulfonic acid (LABSA) intercalation and zeolitic imidazolate framework-8 (ZIF-8) as the shell. Benefiting from the intercalation of LABSA into LDH combined with ZIF-8, the multiple interactions, including π-π stacking, hydrogen bonding, and electrostatic interactions, conferred high selectivity and good extraction capability to the material towards heterocyclic aromatic amines (HAAs). Fe 3 O 4 @Zn/Al-LABSA-LDH@ZIF-8 was used as an adsorbent for magnetic solid-phase extraction (MSPE) to enrich HAAs in thermally processed meat samples, followed by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) detection. The method exhibited a low detection limit (0.021–0.221 ng/g), good linearity (R2 ≥ 0.9999), high precision (RSD < 7.2 %), and satisfactory sample recovery (89.7 % -107.5 %). This research provides a promising approach for developing novel adsorbents in sample preparation and improving analytical performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • The precursor components in the formation of HAAs have been investigated using UPLC-MS/MS. • The results confirmed the previously reported precursors and formation mechanisms of HAAs. • Some potential direct and indirect precursors for HAAs were discovered. The prevention and control of heterocyclic aromatic amines (HAA) formation to mitigate of potential risks to humans, can be achieved by targeting their precursors. In this study, the detailed roles of individual and excess component (20 common α-amino acids, creatine, creatinine, and glucose) on HAA formation in roasted beef patties were examined using UPLC-MS/MS. The results confirmed the reported classical precursors of HAAs. Some components regulated the competitive production of Norharman and Harman. Glycine (Gly) and glucose favored Norharman formation, while cysteine (Cys) and phenylalanine (Phe) for Harman. Serine (Ser) and threonine (Thr) were identified as potential precursors for IQx-type HAAs. Interestingly, methionine (Met), Gly, Thr, Cys, alanine (Ala), and Ser were revealed as more targeted underlying precursors for 1,6-DMIP and 1,5,6-TMIP, and the formation mechanism was inferred. Furthermore, Pro, Leu, His, Ile, Lys and Asp were considered as great inhibitors for HAAs. [ABSTRACT FROM AUTHOR]

Aniline (C 6 H 5 NH 2) is one of the hazardous aromatic amine where an amino group -NH 2) is connected to phenyl ring (C 6 H 5). Based on the evaluation of the 96-hour LC 50 of aniline, two sublethal concentrations (4.19 mg/l and 8.39 mg/l) were selected for acute exposure tests in freshwater fish Channa punctatus. The liver, gills and kidney of fish being the principal sites of xenobiotic material accumulation, respiration, biotransformation, and excretion are the focus of the present study. Throughout the exposure time, the comet assay revealed increased tail length and tail DNA percentage indicating maximum damage to liver, gills and kidney of treated group after 96 h. After acute exposure, there was a significant (p ≤ 0.05) increase in the enzymatic activity of glutathione-S-transferase (GST) and acetylcholinesterase (AChE), whereas decline in superoxide dismutase (SOD) and catalase (CAT) activity was observed. Meanwhile, levels of malondialdehyde (MDA) increased over the exposure period for both concentrations. After 96 h of exposure, degree of tissue change (DTC) was evaluated in liver, gill and kidney of aniline exposed fish. Additionally, light microscopy revealed multiple abnormalities in liver, gills and kidney of all the treated groups. Significant changes were observed in the levels of biochemical markers viz., glucose, triglyceride, cholesterol, aspartate transaminase, alanine transaminase and urea following a 96-hour exposure to aniline. Studies using ATR-FTIR and transmission electron microscopy (TEM) revealed changes in biomolecules and structural abnormalities in several tissues of the aniline-exposed groups in comparison to the control group respectively. [Display omitted] • Aniline exposure induces DNA damage in different organs of test animal. • Aniline exposure caused oxidative stress via alterations in CAT, SOD, GST and AChE activity. • Histopathological alterations were observed by light microscopy and TEM. • ATR-FTIR studies suggested alterations at bio-molecular level. [ABSTRACT FROM AUTHOR]

In situ Raman spectroscopy was used for the first time to study the reaction intermediates/products of the oxidative polymerization of aniline to polyaniline (PANI) with peroxydisulfate in aqueous solutions of different initial acidity. Raman spectra were recorded for the drops of reaction mixture taken at various reaction times. Five reaction systems with different pH of the monomer solution (pH mon), leading to 1-D nanostructured PANIs (pH mon =5.8, 4.6 and 4.5) and granular PANIs (pH mon = 3.4 and 1.0) were explored. Spectral characteristics of different reaction phases - athermal, exothermic and post-propagation were identified and correlated with the proposed mechanisms of aniline polymerization and nanostructures formation. For the nanostructured PANIs, the athermal phase was characterized by pronounced strengthening of the δ(N−H)/ν(C N) Q band at 1510–1520 cm−1, while the characteristic of the second exothermic phase was the strengthening of the ν(C∼C) B /ν(C∼C) Phz band at c.a. 1636 cm−1 which becomes stronger than the ν(C C) Q /ν(C∼C) SQ band at c.a. 1590 cm–1. For granular PANIs, the band at 1590 cm–1 was stronger than that at 1630 cm–1 for all reaction phases. For all reaction systems, characteristic feature of the post-propagation phase was strengthening of the ν(C∼N+•) band at 1330–1340 cm−1 due to delocalized polarons. For granular PANIs, the band associated with phenazine-like units at c.a. 1415 cm−1 disappeared after the exothermic phase, while for nanostructured PANIs it was seen until the end of the reaction. The obtained results are expected to be useful in further investigations of the intermediates/products and mechanisms of polymerizations of other aromatic amines. • The oxidative polymerization of aniline in media of different initial acidity leading to 1-D nanostructured and granular polyanilines (PANIs) was studied by i n situ Raman spectroscopy. • Spectral characteristics of the individual reaction phases athermal, exothermic and post-propagation, were identified. • For nanostructured PANIs the bands at c.a. 1510 cm−1 and 1636 cm−1 showed pronounced strengthening during the athermal and second exothermic phases, respectively. • For nanostructured PANIs the band at c.a. 1636 cm−1 becomes stronger than that at c.a. 1590 cm–1 during the second exothermic phase while inverse intensity ratio characterizes the other phases. • For granular PANIs the band at c.a. 1590 cm–1 is stronger than the band c.a. 1636 cm−1 for all reaction phases. [ABSTRACT FROM AUTHOR]

• RONCs transformation and ammonification is the key step for total nitrogen removal. • The cleavage of C-N bond limited the transformation of electrophilic RONCs to NH 4 +. • Electrostimulation enhances the anaerobic reduction of RONCs into aromatic amines. • Micro-aeration enhances the aerobic oxidation of amine products into NH 4 +. • Regulating microbial redox reactions facilitates the transformation of RONCs. Biotechnology for wastewater treatment is mainstream and effective depending upon microbial redox reactions to eliminate diverse contaminants and ensure aquatic ecological health. However, refractory organic nitrogen compounds (RONCs, e.g., nitro-, azo-, amide-, and N-heterocyclic compounds) with complex structures and high toxicity inhibit microbial metabolic activity and limit the transformation of organic nitrogen to inorganic nitrogen. This will eventually result in non-compliance with nitrogen discharge standards. Numerous efforts suggested that applying exogenous electron donors or acceptors, such as solid electrodes (electrostimulation) and limited oxygen (micro-aeration), could potentially regulate microbial redox reactions and catabolic pathways, and facilitate the biotransformation of RONCs. This review provides comprehensive insights into the microbial regulation mechanisms and applications of electrostimulation and micro-aeration strategies to accelerate the biotransformation of RONCs to organic amine (amination) and inorganic ammonia (ammonification), respectively. Furthermore, a promising approach involving in-situ hybrid anaerobic biological units, coupled with electrostimulation and micro-aeration, is proposed towards engineering applications. Finally, employing cutting-edge methods including multi-omics analysis, data science driven machine learning, technology-economic analysis, and life-cycle assessment would contribute to optimizing the process design and engineering implementation. This review offers a fundamental understanding and inspiration for novel research in the enhanced biotechnology towards RONCs elimination. [Display omitted] [ABSTRACT FROM AUTHOR]

Due to animal meat's carcinogenic concern, plant-based consumption is increasing. However, the existence of cooking-derived carcinogens in plant-based meat was unknown. This study compared Heterocyclic Aromatic Amines (HAAs) and Polycyclic Aromatic Hydrocarbons (PAHs) levels in grilled plant-based patties with those of beef patties. HAAs and PAHs levels were measured by using LC-MS/MS and GC-HRMS, respectively. At equal percent of added oil, the total PAHs (BaA, chrysene, BbF, and BaP) levels in Riceberry rice, brown rice, and yellow corn-based patties were higher than those of beef (p < 0.05). In contrast, the total PAHs in soy and white corn were not significantly different from those of beef. At equal shape and size of patties, HAAs (PhIP and MeIQx) levels in all plant-based patties were lower than those of beef (p < 0.0001), with the lowest in yellow and white corns. Nevertheless, the level of PhIP in soy is still high close to that of beef. The findings suggest that HAAs but not PAHs in grilled plant (soy, rice, corn)-based patties are lower than those of beef patties. Preventive measures to reduce PAHs and HAAs may be required when cooking rice and soy products. Corn could be a low-carcinogenic plant-based ingredient, deserving further exploration. • The first study of cooking-derived carcinogens in grilled plant-based patties. • Lower HAAs but higher PAHs are found in plant-based patties than in beef patties. • PAHs in grilled plant-based patties are within safe limits of European Standards. • Corn could be a low-carcinogenic plant-based ingredient. • When cooking, PAHs in rice- and HAAs in soy-based patties should be controlled. [ABSTRACT FROM AUTHOR]

p -Phenylenediamine (PPD) serves as an important intermediate in materials chemistry and is widely used in the preparation of azo dyes and high polymers. However, the discharge of wastewater from industries containing PPD can pose significant threats to both the environment and human health. Herein, a sensitive and reversible β-ketoenamine-based covalent organic framework (TD-COF) fluorescent probe was fabricated with ketoamine-substituted monomers for detection and facile removal of PPD. Abundant carbonyl groups, the regular pores, and the π-conjugated structure of TD-COF are the key features that help facilitate TD-COF interaction with the analyte. Based on these advantages, TD-COF displayed a low detection limit (0.35 μM), high sensitivity, easy visibility, real-time response, and selective interaction with PPD. Simultaneously, the effective removal of PPD and the circulating utilization of TD-COF provide the potential for practical production applications. Regeneration experimental studies indicated that TD-COF retained satisfactory structural stability after five cycles. Furthermore, based on solid-state NMR, X-ray photoelectron spectroscopy, and density functional theory calculations, these studies verified that hydrogen bonding and π-π interaction mechanisms contribute to fluorescence quenching between PPD and the carbonyl of TD-COF. The research demonstrated the utilization of fluorescent COFs for the sensing and removal of PPD, with the potential for extension to the detection of other pollutants. [Display omitted] • TD-COF has realized the selective detection of p -phenylenediamine. • The fluorescence quenching of TD-COF can be attributed to the formation of hydrogen bonds and π-π interaction between p -phenylenediamine and TD-COF. • The mechanism's contribution to fluorescence quenching has been confirmed through 13 C CP/MAS NMR, XPS, FT-IR, and DFT calculations. [ABSTRACT FROM AUTHOR]

• Large amounts of biogenic amines are produced during fermentation. • Treatment with activated carbon removes biogenic amines from the fish sauce. • Activated carbon can preserve the original taste and color of the fish sauce. This study aimed to efficiently reduce a large number of biogenic amines in salt-fermented fish sauce while minimizing sensory reduction using various activated carbons. Aromatic amines, such as tryptamine and phenethylamine, were reduced by 86.1–100 % after treating with activated carbon. Histamine with a heterocyclic structure decreased by 13–42 %. No significant effects were observed on the levels of aliphatic amines, putrescine, cadaverine, spermine, and spermidine. The major taste component, amino acid nitrogen, was reduced to within 3 %, and brown color removal was reduced depending on the type of activated carbon used. Acid-modified AC-A and AC-B had rough surfaces, high total acidity, low point of zero charge (pHpzc), and rich surface functional groups. Owing to its smooth surface, low total acidity, high pHpzc, and few surface functional groups, AC-C exhibited a higher histamine elimination and less color reduction despite its lower surface area compared to other activated carbons. [ABSTRACT FROM AUTHOR]

[Display omitted] • Spices and phenols reduced the heterocyclic aromatic amines (HAAs) in roasted beef. • The HOMO/LUMO and ESP were analyzed by density functional theory (DFT). • Intermediates of HAAs exhibited intermolecular interactions with phenols. • The imino and hydroxyl group of capsaicin captured HAAs-related free radicals. • This study provided a reference for the development of DFT in the control of HAAs. The ability of spices (bay leaf, star anise, and red pepper) and their characteristic phenolic compounds (quercetin, kaempferol, and capsaicin) to inhibit Heterocyclic aromatic amines (HAAs) in roasted beef patties were compared. Density functional theory (DFT) was used to reveal phenolic compounds interacting with HAAs-related intermediates and free radicals to explore possible inhibitory mechanisms for HAAs. 3 % red chili and 0.03 % capsaicin reduced the total HAAs content by 57.09 % and 68.79 %, respectively. DFT demonstrated that this was due to the stronger interaction between capsaicin and the β-carboline HAAs intermediate (E bind = –32.95 kcal/mol). The interaction between quercetin and phenylacetaldehyde was found to be the strongest (E bind = −17.47 kcal/mol). Additionally, DFT indicated that capsaicin reduced the carbonyl content by transferring hydrogen atoms (HAT) to eliminate HO·, HOO·, and carbon-centered alkyl radicals. This study provided a reference for the development of DFT in the control of HAAs. [ABSTRACT FROM AUTHOR]

3-Aminodibenzofuran (3-ADBF) is a potent bladder carcinogen. This study aimed to identify reactive metabolites and the metabolic pathways of 3-ADBF. The in vitro and in vivo studies demonstrated that 3-ADBF was oxidized to the corresponding hydroxylamine by cytochrome P450 enzymes, followed by sulfation of the hydroxyl group mediated by sulfotransferases. The resulting sulfate conjugate was chemically reactive to GSH and cysteine residues of hepatic protein to form the corresponding GSH conjugate and protein adduction. Exposure of 3-ADBF to primary hepatocytes caused protein covalent binding and decreased cell viability. The resultant protein adduction was found to correlate the observed cytotoxicity of 3-ADBF. [Display omitted] • 3-Aminodibenzofuran (3-ADBF) was metabolized to a reactive nitrenium ion intermediate. • Cysteine-based protein adduction derived from the reactive intermediate was observed. • Protein covalent modification was associated with 3-ADBF-induced hepatocyte toxicity. • P450 and sulfotransferase participated in the metabolic activation. [ABSTRACT FROM AUTHOR]

• Two new BODIPY derivatives, 6a and 6b, with truxene moiety and triphenylamine were prepared. • The optical and electrochemical properties were investigated. • The photovoltaic properties of organic solar cells OSCs were investigated. • The ternary OSCs based on the 6a : PC 71 BM : Y6 and 6b : PC 71 BM : Y6 showed high Power Conversion Efficiency of 11.37 % and 13.32 %, respectively. • The reason of the higher power conversion efficiency for ternary OSC was clarified. We have designed two new BODIPY derivatives, denoted as 6a and 6b, substituted with truxene moiety and triphenylamine (TPA) unit groups and have investigated their optical and electrochemical properties. Dyes 6a and 6b were employed as donor along with PC 71 BM or Y6 as acceptor for the fabrication of binary and ternary organic solar cells. After optimization of the binary and ternary active layers, we have achieved over all power conversion efficiency (PCE) of 11.37 % and 13.32% for 6a : PC 71 BM : Y6 and 6b : PC 71 BM : Y6 ternary organic solar cells, respectively, which are higher than the binary organic solar cells based on PC 71 BM or Y6 acceptor. The higher power conversion efficiency for ternary OSC is possibly attributed to the better exciton generation rate, exciton dissociation and charge collection. [ABSTRACT FROM AUTHOR]

[Display omitted] • We have investigated the effect of amines on the optical properties of 2D perovskites. • The 2D perovskites are synthesized by adopting the ligand assisted reprecipitation (LARP) technique. • By varying the amines, we have observed various shapes like quantum dots, cubic shape and nanorods depend on the length of the carbon chain attached to the benzylamines. • The optical properties also vary with the different benzyl amines, the absorption peak of less carbon chain length benzyl amine perovskites showed at shorter wavelength compared to the long alkyl chain benzyl amines. • The PLQY and lifetime are high with the long carbon chain benzyl amine perovskites 4TBAHD and 3 TFMBAHD. Due to environmental stability issues and the presence of lead in high-performing 3D perovskites and organic 2D perovskites have emerged as excellent light-harvesting materials and gained immense attention for optoelectronic applications such as perovskite solar cells (PSCs) as a capping layer as well as a light-harvesting material. In this paper, we have investigated the effect of varying the type of aromatic amines (benzylamines) and alkyl chain length (hexadecyl and tetradecyl substituted benzylamines), incorporated into organic halide 2D perovskites, on their optoelectronic properties. We synthesized the 2D perovskites were synthesized by adopting the ligand assisted reprecipitation (LARP) technique and analysed their optical properties by using the UV–Visible and Photoluminescence, structural composition using thin-film XRD and morphology analysis using scanning and transmission electron microscopy (SEM and TEM). Our experimental finding suggests the formation of various shapes such as quantum dots, cubic shapes and nanorods which depend on the length of the carbon chain attached to the benzylamines. [ABSTRACT FROM AUTHOR]

Ammonia and cyclic aromatic compounds are principal products from combustion of various fractions of biomass. Yet, kinetic mechanistic models on formation of NO x from biomass de-couple the oxidation mechanism of ammonia from that of aromatic molecules. Literature kinetic models do not consider a plausible formation of aniline as the initial product from the interaction of amine radicals and benzene molecules (as the simplest aromatic molecule). Such reaction acts a sink for NH 2 radicals, and thus may alter the yields of NO x and HCN. To fill in this gap, this study reports production pathways of aniline from NH 2 + benzene reactions, maps out unimolecular decomposition pathways of aniline and its derived anilino radical into, and explores the effect of the title reaction on the yields of small nitrogenated species from co-combustion of ammonia and benzene. We find that anilino radical to preferentially decompose into iso -HNC and a cyclopentadienyl radical. The resonance-stabilized structure of the anilino radical enables it to undergo bimolecular reaction with the aniline molecule to generate N-analogous compounds of dioxins, namely diphenylamine, carbazole, and phenazine. Detail kinetic modeling discloses that decomposition of aniline initiates at 1100 K with ammonia and HCN signify the most abundant N-bearing species at intermediates and high temperatures, respectively. Introducing the newly constructed aniline sub-mechanism in NO x + benzene kinetic model from the literature (i.e., CERCK model) alters predicted concentrations of principal N species within factors of 1.2- 2 between 1100–1300 K. It is hoped that reaction rate constants and mechanistic pathways presented herein to improve the predictive performance of kinetic models that address NO x and HCN emission from flames of ammonia and aromatic-containing fuels in general. [ABSTRACT FROM AUTHOR]

Heterocyclic aromatic amines (HAAs) are the main carcinogens produced during thermal processing of protein-rich foods. In this paper, a composite aerogel (TOCNFCa) with a stabilized dual-network structure was prepared via a template for the in-situ synthesis of UiO-66 on cellulose for the adsorption of HAAs in food. The dual-network structure of TOCNFCa provides the composite aerogel with excellent wet strength, maintaining excellent compressive properties. With the in-situ grown UiO-66 content up to 71.89 wt%, the hierarchical porosity endowed TOCNFCa@UiO-66 with the ability to rapidly adsorb HAAs molecules with high capacity (1.44–5.82 μmol/g). Based on excellent thermal stability, adsorption capacity and anti-interference, TOCNFCa@UiO-66 achieved satisfactory recoveries of HAAs in the boiled marinade, which is faster and more economical than the conventional SPE method. Moreover, TOCNFCa@UiO-66 could maintain 84.55 % of the initial adsorption capacity after 5 times of reuse. [Display omitted] • The thawing crosslinking strategy gives TOCNFCa a stable double cross-linking structure. • UiO-66 grew in situ on TOCNFCa@UiO-66 up to 71.89 wt%. • TOCNFCa@UiO-66 can be used for rapid and large-capacity adsorption of HAAs. • TOCNFCa@UiO-66 can significantly reduce the time and cost of pre-treatment methods for HAAs. [ABSTRACT FROM AUTHOR]