Search

Process intensification is crucial for industrial implementation of biocatalysis and can be achieved by continuous process operation in miniaturized reactors with efficiently immobilized biocatalysts, enabling their long-term use. Due to their extremely large surface-to-volume ratio, nanomaterials are promising supports for enzyme immobilization. In this work, different functionalized nanofibrous nonwoven membranes were embedded in a two-plate microreactor to enable immobilization of hexahistidine (His 6 )-tagged amine transaminases (ATAs) in flow. A membrane coated with Cu 2+ ions gave the best results regarding His 6 -tagged ATAs immobilization among the membranes tested yielding an immobilization yield of up to 95.3 % for the purified N-His 6 -ATA-wt enzyme. Moreover, an efficient one-step enzyme immobilization process from overproduced enzyme in Escherichia coli cell lysate was developed and yielded enzyme loads up to 1088 U mL -1 . High enzyme loads resulted in up to 80 % yields of acetophenone produced from 40 mM (S)-α-methylbenzylamine in less than 4 min using a continuously operated microreactor. Up to 81 % of the initial activity was maintained in a 5-day continuous microreactor operation with immobilized His 6 -tagged ATA constructs. The highest turnover number within the indicated time was 7.23·10 6 , which indicates that this immobilization approach using advanced material and reactor system is highly relevant for industrial implementation., Competing Interests: Declaration of Competing Interest On behalf of all the authors of a submission I hereby disclose no competing interest. Prof. Dr. Polona Žnidaršič-Plazl., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Knowledge of antibiotic desorption from high-temperature biochar is essential for assessing their environmental risks, and for the successful application of biochar to remove antibiotics. In previous studies, irreversible pore deformation, formation of charge-assisted hydrogen bonds or amide bonds were individually proposed to explain the desorption hysteresis of antibiotics on biochars, leading to a debate on hysteresis mechanism. In this study, desorption of sulfamethoxazole (SMX), ciprofloxacin (CFX) and tetracycline (TET) on a wood chip biochar produced at 700 °C (WBC700) and its oxidized product (O-WBC700) was investigated to explore the underlying hysteresis mechanism. Significant desorption hysteresis was observed for SMX, CFX and TET on WBC700 and O-WBC700. Hysteresis index (HI) of each antibiotic was higher on O-WBC700 with more oxygen-containing groups than WBC700, and was higher at lower equilibrium concentration. HI of antibiotics on WBC700 (or O-WBC700) increased in the order of SMX < CFX < TET. The calculated adsorption enthalpy of each antibiotic on WBC700 was positive, indicating an endothermic process. These phenomena together with FTIR, XPS spectra confirmed that the desorption hysteresis mechanism of antibiotics on high-temperature biochar is the formation of amide bonds by amidation reaction, but not the pore deformation or the hydrogen bond. Moreover, antibiotic can form amide bonds with WBC700 only if the amine group with pK a  > 4.0, and the HI values were positively correlated with their pK a values. Amine group of antibiotics with higher pK a value show more nucleophilicity and could form stronger amide bonds with carboxyl group of biochar. The obtained results could help to solve the debate on desorption hysteresis mechanism of antibiotics on high-temperature biochars, and provide a new insight into the role of amine groups and amidation reaction on the hysteresis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The thiophene- and pyrrole-fused heterocyclic compounds have garnered significant interest for their distinctive electron-rich characteristics and notable optoelectronic properties. However, the construction of high-performance systems within this class is of great challenge. Herein, we develop a series of novel dithieno[3,2-b:2',3'-d] pyrrole (DTP) and tetrathieno[3,2-b:2',3'-d] pyrrole (TTP) bridged arylamine compounds (DTP-C 4 , DTP-C 12 , DTP-C 4 -Fc, TTP-C 4 -OMe, TTP-C 4 , and TTP-C 12 ) with varying carbon chain lengths. The pertinent experimental results reveal that this series of compounds undergo completely reversible multistep redox processes. Notably, TTP-bridged compounds TTP-C 4 and TTP-C 12 exhibit impressive multistep near-infrared (NIR) absorption alterations with notable color changes and electroluminescent behaviors, which are mainly attributed to the charge transfer transitions from terminal arylamine units to central bridges, as supported by theoretical calculations. Additionally, compound DTP-C 4 demonstrates the ability to visually identify gram-positive and gram-negative bacteria. Therefore, this work suggests the promising electroresponsive nature of compounds TTP-C 4 and TTP-C 12 , positioning them as excellent materials for various applications. It also provides a facile approach to constructing high-performance multifunctional luminescent materials, particularly those with strong and long-wavelength NIR absorption capabilities., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In recent years, mussel-inspired polydopamine (PDA)-based materials have attracted significant attention in the field of open-tubular capillary electrochromatography (OT-CEC) owing to their diverse and appealing properties. However, previously established functionalized PDA coating-based CEC stationary phases predominantly relied on the latent reactivity of PDA with amine/thiol-containing molecules, limiting the types of applicable modifiers and requiring time-consuming reaction processes. Herein, we presented a versatile and efficient method for the facile and rapid fabrication of diverse functionalized PDA coatings as OT-CEC stationary phases through a Zr(IV) coordination-mediated post-modification strategy. Different kinds of modifiers, including octadecylamine (ODA), lauric acid (LA), and perfluorooctanoic acid (PFOA), were rapidly and robustly grafted onto the PDA coating, verified through multiple characterization techniques. The influences of preparation parameters on the grafting efficiency of the functionalized PDA coating were systematically investigated. Utilizing the Zr(IV)-mediated ODA-, LA- and PFOA-functionalized PDA-based OT-CEC columns, we achieved high-efficiency baseline separation of a series of neutral analytes with excellent repeatability, good stability, and long lifetime. Given the strong universality of the Zr(IV) coordination-mediated post-modification approach, our study provides an effective pathway for advancing the development of a wider range of functional PDA-based chromatographic stationary phases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Metal complexes showing dual activity against cancer and bacterial infections are currently the focus of significant interest for their potential in treating life-threatening diseases. Aiming to investigate the impact of ligand substituents on these bioactivity properties of Group 11 d 10 metal complexes, we herein present a series of mononuclear Cu(I) and Ag(I) complexes featuring the bis-NH 2 -substituted heterocyclic thioamide dap2SH (=4,6-diaminopyrimidine-2-thione), namely [AgCl(dap2SH)(PPh 3 ) 2 ] (1), [CuBr(dap2SH)(PPh 3 ) 2 ] (2), [CuBr(dap2SH)(xantphos)] (3), [Ag(dap2S)(xantphos)] (4), and [Cu(dap2S)(xantphos)] (5) (xantphos = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene). Complexes were characterized by means of different physicochemical methods (i.e., single crystal X-ray diffraction as well as FTIR, NMR, UV-Vis and fluorescence spectroscopy), and studied in-vitro for their antibacterial and anticancer activity against a variety of bacterial strains and cancer cell lines. Complexes 1-3 effectively inhibited both Gram (+) and Gram (-) bacterial growth, while cellular uptake studies for the most potent complex 1 against E. coli bacteria revealed the accumulation of Ag(I) ions in the periplasm of the bacteria. A high anti-proliferative effect was observed for 1 and 5 against A549, MCF7 and PC3 cancer cell lines, with 1 being capable of inducing apoptosis in A549 cells, as suggested by flow cytometry analysis. DNA interaction studies revealed the capacity of 1 to intercalate between base-pairs of CT DNA. All complexes had a moderate-to-high capacity to scavenge free radicals preventing oxidative stress. Molecular docking calculations, in combination with the experimentally obtained data, provided insights for potential mechanisms of the bioactivity of the complexes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

An ethanol extract of Piper auritum leaves (PAEE) inhibits the mutagenic effect of three food-borne aromatic amines (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP); 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx); 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx)) in the TA98 Salmonella typhimurium strain. Preincubation with MeIQx demonstrated in mutagenesis experiments that inhibition of Cytochrome P450 (CYP), as well as direct interaction between component(s) of the plant extract with mutagens, might account for the antimutagenic observed effect. Gas chromatography/mass spectrometry analysis revealed that safrole (50.7%), α-copaene (7.7%), caryophyllene (7.2%), β-pinene (4.2%), γ-terpinene (4.1%), and pentadecane (4.1%) as the main components (PAEE). Piper extract and safrole were able to inhibit the rat liver microsomal CYP1A1 activity that participates in the amines metabolism, leading to the formation of the ultimate mutagenic/ molecules. According to this, safrole and PAEE-inhibited MeIQx mutagenicity but not that of the direct mutagen 2-nitrofluorene. No mutagenicity of plant extract or safrole was detected. This study shows that PAEE and its main component safrole are associated with the inhibition of heterocyclic amines activation due in part to the inhibition of CYP1A subfamily activity., (© The Author(s) 2024. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society.)

Demethylation modification of lignin is an effective strategy to overcome the barrier to its high-value conversion. The purpose of this study focuses on the new proton-based ionic liquid (PIL) 1, 2-propanediamine/glycolic acid (PD/GA) as a catalyst and solvent to achieve the targeted oxidation of lignin. The PD/GA solvents have higher selectivity and efficiency. Optimal phenolic hydroxyl (PH)-increment was achieved, demonstrating enhanced demethylating effect on lignin by modulating the acid-base molar ratio, reaction temperature, and reaction time. Compared to ethanolamine/acetic acid (CE/AC) treatment, the PD/GA treatment at molar ratio 1.25, temperature 60 °C, and 3 h increased the PH-content from 37.74 to 59.91 %. Additionally, the lignin treated with PD/GA exhibited excellent recyclability, featuring a larger Brunauer-Emmett-Teller surface area (1.45 m 2 .g -1 ), total pore volume (9.51*10 -3  cm 3 .g -1 ), and mesoporous size (26.15 nm). The treated lignin yielded maximum ultraviolet resistance and antioxidant activity. These results present new avenues for the development of green and efficient lignin demethylation methods., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Amine functionalized bentonites were used as adsorbents for the bioremoval of Fe(III) ions, which led to the inclusion of functional groups such as -OH, -NH2, -OCH3, etc. FTIR, XRD, SEM, AFM, TG, BET, XRF, and CHNS analyzer were used to analyze the surface and textural characteristics. The influence of adsorption factors, such as pH, contact time, temperature, and initial concentration, have been investigated and tailored in batch adsorption experiments of Fe (III) metal ions. The maximum adsorption efficiency and capacity of modified BNT-APTMS is 100.90 % and 103.91 mg/g respectively. The adsorption process is best fit with Freundlich model (R 2 =0.998) than Langmuir model (R 2 =0.788) and the Temkin model D-R isotherm parameters indicating a physisorption process. A mechanism of spontaneous complexation was accomplished, because of the heterogeneity of the surface, electrostatic forces, pore filling, and π-π stacking. Follows PSO kinetics and favours Freundlich isotherm. The adsorbent substance showed a remarkable capacity for regeneration, assuring the substance's stability and reusability., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Industrial gelatin is a good candidate for fabricating biodegradable packaging film, but the strong hydrophilicity of gelatin-based film lowers its moisture service reliability. Herein, we demonstrated a low surface energy water repellency surface design combined with covalent cross-linking for decreasing the water absorption and improving the moisture service reliability. Biodegradable octadecylamine (ODA) was chosen as the low surface energy providing material to fabricate the water repellency surface through a dehydration condensation reaction between the amine groups of ODA and gelatin chains via tetra-hydroxymethyl phosphonium chloride (THPC) in an aqueous phase. THPC also was employed as the cross-linking agent to form covalent bonding between the gelatin chains. The results determined that ODA modification and covalent cross-linking endowed the gelatin-based film with good water repellency and improved moisture service reliability. But high dose of ODA would result in phase separation and mechanical strength loss of the fabricated film. Additionally, ODA modification did not change the biodegradability of gelatin-based film, all the modified films were completely biodegradable in natural soil. Considering the sustainable modification process and abundant raw materials, the proposed strategy facilitates the effective utilization of low value industrial gelatin and provides a facile way for gelatin-based film as biodegradable packaging film., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this work, coacervation in primary amines solutions with hydrophobic natural deep eutectic solvents based on terpenoids and carboxylic acids was demonstrated for the first time. A liquid-phase microextraction approach was developed based on supramolecular solvent formation with primary amine acting as amphiphile and hydrophobic deep eutectic solvent making up mixed vesicles and serving as coacervation agent. Such supramolecular solvents could be used to separate wide range of substances from different aqueous media, such as food products, biological liquids and wastewaters. It is important that both hydrophobic and ionic interactions with supramolecular aggregates take place ensuring synergetic effect and better extraction ability, which is significant in separating relatively polar analytes. Different primary amines and deep eutectic solvents were investigated for liquid-phase microextraction of proof-of-concept amphoteric analyte (enrofloxacin, widely used veterinary fluoroquinolone antibiotic) and its determination by high-performance liquid chromatography with fluorescence detection using Shimadzu LC-20 Prominence chromatograph and RF-20A fluorescence detector. It was found that the supramolecular solvent based on 1-nonylamine, formed after addition of a deep eutectic solvent based on menthol and hexanoic acid (molar ratio of 1:1), provided maximum extraction recovery (85 %) and maximum enrichment factor (34). To characterize the extraction system, the composition of the phases was investigated, and cryo-transmission electron microscopy images were obtained. Vesicular aggregates were observed in the supramolecular solvent. The extraction mechanism was proposed in terms of formation of mixed aggregates to capture the analyte. Limit of detection was found to be 7 μg kg -1 , while linear range of 20-250 μg kg -1 was established. Relative standard deviation values were lower than 7 %. Relative bias did not exceed 12 %., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Perfluorinated alkylated substances (PFAS), as a category of persistent organic pollutants, have garnered extensive concern due to their resilience against environmental degradation. Herein, we developed an amine-functionalized sphalerite (ZnS) with adjustable surface amine functional groups and Zn defects (ZnS-X%[N]) by in situ coprecipitation and simple hydrothermal method in the presence of cetyltrimethylammonium bromide (CTAB). This material demonstrated efficient PFAS adsorption and subsequent photo-induced degradation under UV irradiation. The characterization results by TEM, BET, FTIR, XPS and EPR revealed that CTAB primarily influences ZnS by modulating surface amine functionalities, zinc defect density, and enhancing its photoreductive capacity. Adsorption and kinetic degradation experiments further showed that a medium CTAB concentration in ZnS-40%[N] achieves highest PFAS adsorption capacity (C max : 0.201 mol kg -1 ), and the corresponding decomposition rate was the fastest (k de : 1.53; k df : 1.19). This efficacy is attributed to the ZnS-40%[N]'s ideal adsorptive sites and surface shallow defects. Moreover, theoretical simulation also supports the above experimental inference. Overall, ZnS-X%[N] exhibits a synergistic effect on PFAS adsorption and degradation, showcasing its potential for environmental adaptability and practical application., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

The clarification conditions and the selection of the clarification agent are pivotal in eliminating the haze components from red grape juice (RGJ) while minimizing the loss of functional color components. In this context, we synthesized a water glass-based APTES functionalized magnesium silica aerogel (MSA-NH 3 ) incorporating 61.44 molecules/nm 2 of amine groups, resulting in a positively charged zeta potential value of 33.9 mV (pH 3.4) for clarification of RGJ by targeting negatively charged polyphenols. The optimum clarification conditions using MSA-NH 3 were determined as 0.18 g MSA-NH 3 /L RGJ, 20 °C, and 60 min through the application of Box-Behnken design. Under these conditions, MSA-NH 3 exhibited excellent adsorption of haze components (3.61 NTU), outperforming the commercial bentonite-gelatine combination (BGC) (5.45 NTU). Furthermore, it exhibited greater efficacy in preserving anthocyanins while adsorbing browning components. MSA-NH 3 has a high potential to serve as a functional alternative clarification agent in the beverage industry due to its promising clarification performance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The outbreak of the 2019 coronavirus pandemic has raised worldwide attention about self-protection from airborne diseases. Air filtration and wearing mask have been proven to be effective measures in reducing the pathogenic aerosol's transmission. Those lead to an increasing demand of high-efficient filters. However, the nonbiodegradable polymeric materials used in filters can accumulate in landfills or ecosystems, potentially causing pollution after improper disposals. Sustainable and biodegradable alternatives to current filter materials are urgently needed. Yet, very few commercial filters meet these needs. In this paper, a novel quaternary ammonium-halamine compound containing Schiff base and a sandwich-structured preparation strategy were developed. The obtained multifunctional filter consists of a PLA fleece as a support layer, an antimicrobial coating for bactericidal function, and a nanofibrous membrane for the particle removal. The filter demonstrates strong bactericidal properties, killing 97% of Escherichia coli and Staphylococcus aureus at a biocide concentration of only 1 mg/mL. It can rapidly kill bacteria within 5 min contact without leaching antimicrobial substances. Furthermore, it boasts a filtration performance with a success rate over 99.99% and a pressure drop of 45 Pa, which surpasses that of commercial N95 filters for PM0.3. Even under humid conditions, it maintains excellent filtration performance. Our reusability testing result of the developed filters shows that a simple halogenation treatment can renew the halamines and restore the filter's antimicrobial activity. The filters can degrade in natural soil. The successful development of this sustainable and biodegradable filter material offers a new alternative for high-performance air quality control that protect public health.

A series of new hydroxylated fatty amine derivatives, albusamides A-G ( 1 - 7 ), along with four known compounds ( 8 - 11 ), which are reported for the first time from a natural source, were isolated from the culture broth of Streptomyces albus 228DD-066 derived from a deep-sea sediment sample gathered off the coast of Dokdo Island, Republic of Korea. Their structures were elucidated through the comprehensive analysis of 1D and 2D NMR spectra and HRESIMS, and absolute configurations were determined using the modified Mosher's method. Biological evaluations against solid and blood cancer cell lines revealed that these new metabolites have moderate to strong cytotoxic activity. Compound 3 exhibited high cytotoxic activity with GI 50 values ranging from 0.4 to 0.6 μM against solid cancer cell lines and exhibited the strongest cytotoxicity (GI 50 value = 0.2 μM) against the WSU-DLCL2 blood cancer cell line.

Disposal of the cow dung pollutants arising from cattle farming threatens the environment and public safety in diverse ways. To date, researchers have worked on developing new pathways to control and manage cattle farming wastes, but most do not involve the reuse of these wastes. Herein, a cow dung biochar-modulated photothermal N -halamine hydrogel (i.e., PAN/CA/CoBC/pMAG-Cl) was designed for converting cow dung into biochar (CoBC), which was then coupled with a 3D interpenetrating hydrogel network to treat infected wounds. The PAN/CA/CoBC/pMAG-Cl hydrogel exhibited excellent synergistic antibacterial performance against 10 6 CFU·mL -1 Escherichia coli ( E. coli ) and Staphylococcus aureus ( S. aureus ) within 60 min. The bactericidal effect was multimodal, involving CoBC-based photothermal killing (i.e., temperature as high as 80.5 °C) after 808 nm near-infrared light irradiation for 10 min, contact killing through the strong oxidative characteristic of N -halamine (pMAG-Cl), and release killing via active halogens (i.e., Cl + ) reinforced by the photothermal action of CoBC. The S. aureus -infected wound model in vivo demonstrated that the PAN/CA/CoBC/pMAG-Cl hydrogel worked as an ideal wound dressing, capable of resisting bacterial infection, accelerating the healing process, and promoting epithelial regeneration. This proposed strategy could indicate a new way for the disposal of cow dung pollutant and its reuse in antibacterial-associated applications.

Carcinogenic nitrosamines have been widely studied due to their risk to human health. However, the universality and evolutionary processes of their generation, particularly concerning their secondary sources, remain unclear at present. We demonstrated through laboratory flow tube experiments that corresponding nitrosamines were generated from heterogeneous reactions of nitrous acid (HONO) with five structurally diverse amines commonly found indoors, including diphenylamine (DPhA), dibenzylamine (DBzA), dioctylamine (DOtA), N -(1,3-dimethylbutyl)- N '-phenyl- p -phenylenediamine (6PPD), and N -phenyl-1-naphthylamine (PANA). The heterogeneous reaction rate constants of DBzA and DOtA with HONO (∼70 ppb) were 1.21 × 10 -3 and 2.13 × 10 -3 min -1 at 30% relative humidity (RH), resulting in a lifetime of 13.8 and 7.8 h. As compared to higher RH (∼80%), more nitrosamines were produced from the reaction of HONO with surface-sorbed DBzA, DOtA, 6PPD, and PANA at lower RH (30%), with product yields ranging from <0.1% to 0.5%. Furthermore, we observed the formation of nitroso-6PPDs and nitro-6PPDs during room air exposure of 6PPD in a genuine indoor environment, in addition to various other transformation products indicative of reactions of 6PPD with HONO, NOx, and ozone indoors. This study confirmed the universality of the heterogeneous reaction of surface-sorbed amine with HONO as a source of nitrosamines indoors.

Microbial fermentation has provided fermented foods and important chemicals such as antibiotics, amino acids, and vitamins. Metabolic engineering of synthetic microbes has expanded the range of compounds produced by fermentation. Petroleum-derived aromatic compounds are widely used in industry as raw materials for pharmaceuticals, dyes, and polymers and are in great demand. This review highlights the current efforts in the microbial production of various aromatic chemicals such as aromatic amines, cinnamic acid derivatives, and flavoring aromatics, including their biosynthesis pathways. In addition, the unique biosynthetic mechanism of pyrazine, a heterocyclic compound, from amino acids is described to expand the use of biomass-derived aromatic compounds. I also discuss our efforts to develop high-performance bioplastics superior to petroleum plastics from the aromatic compounds produced by microbial fermentation., (© The Author(s) 2024. Published by Oxford University Press on behalf of Japan Society for Bioscience, Biotechnology, and Agrochemistry.)

We report a general approach for efficient deuteration of the metabolically labile α-C-H bonds of widespread amides and amines. Temporarily masking the secondary amine group as a carbamate allows an unprecedented photoredox hydrogen atom transfer-promoted α-carbamyl radical formation for efficient H/D exchange with D 2 O. The mild protocol delivers structurally diverse α-deuterated secondary amines including "privileged" piperidine and piperazine structures highly regioselectively with excellent levels of deuterium incorporation (≤100%). Furthermore, we successfully implemented the strategy for α-deuteration of amides, lactams, and ureas with high regioselectivity and high levels of D incorporation. Finally, the observed efficient deuteration of secondary alcohol moieties in late-stage modification of complex amine-containing pharmaceuticals allows for the development of a viable method for efficient α-deuteration of the important functionality.

The reactivity of Morita-Baylis-Hillman Adduct (MBHA) derivative 7 was studied with different primary amine derivatives such as n-butylamine, Nα-acetyl-L-lysine methyl ester, and a poly-(L-lysine) derivative as lysine models to obtain information about the possible reactions in complex protein environments. MBHA derivative 7 reacted with n-butylamine or Nα-acetyl-L-lysine methyl ester producing monoadducts 9a or 9c, which showed bright emission features in the green region at 526-535 nm with photoluminescence quantum yield values in solutions of 73 % and 51 %, respectively. Based on these results, MBHA derivative 7 can be considered an interesting new fluorogenic probe potentially useful in the labelling of basic amino acid residues. Furthermore, similar to other MBHA derivatives, compound 7 showed the tendency to produce diadducts especially in polar solvents system where specific interactions between the extended aromatic moieties may play a major role., (© 2024 The Authors. Chemistry - An Asian Journal published by Wiley-VCH GmbH.)

Mass cytometry is a bioanalytic tool based on atomic mass spectrometry for detecting biomarker expression on individual cells. Current reagents employ metal-chelating polymers binding isotopes of hard metal ions. Polymers bearing chelators for soft metal ions offer the promise for a large increase in multiplexing capabilities, but examples reported so far often have unacceptably high levels of nonspecific binding (NSB). We recently reported a new class of metal-chelating polymers with dipicolylamine (DPA) chelators that could bind Re and Pt. They also showed significant levels of NSB. Here, to reduce the NSB of the Pt-DPA polymer, we grafted water-soluble oligomers to the distal end of the dipicolylamine pendant group. Methoxy(polyethylene glycol) (DP = 24) was effective as was poly(sulfobetaine methacrylate) (DP = 29). Reacting the Pt-Cl bond of the metalated polymer with glutathione was remarkably effective at suppressing NSB. These results open the door to Pt-isotope-based metal-chelating polymers as new mass tags for mass cytometry.

Cationic amphipathic antimicrobial agents inspired by antimicrobial peptides (AMPs) have shown potential in combating multidrug-resistant bacteria because of minimal resistance development. Here, this study focuses on the development of novel cationic amphipathic macromolecules in the form of dendrons and polymers with different molecular weights that employ secondary amine piperidine derivative as the cationic moiety. Generally, secondary amine compounds, especially at low molecular weights, have stronger bacteriostatic, bactericidal, and inner membrane disruption abilities than those of their primary amine counterparts. Low molecular weight D2 dendrons with two cationic centers and one hydrophobic dodecyl chain produce outstanding synergistic activity with the antibiotic rifampicin against Escherichia coli , where one-eighth of the standalone dose of D2 dendrons could reduce the concentration of rifampicin required by up to 4000-fold. The low molecular weight compounds are also less toxic and therefore have higher therapeutic index values compared to compounds with larger molecular weights. This study thus reveals key information that may inform the design of future synthetic AMPs and mimics, specifically, the design of low-molecular-weight compounds with secondary amine as the cationic center to achieve high antimicrobial potency and biocompatibility.

Bacteria-infected wounds and antibiotic misuse have become a challenge in the treatment of clinical infections. Therefore, there is an urgent need to design non-antibiotic-dependent multifunctional wound dressings for the treatment of bacterially infected wounds. In this study, an injectable antibacterial hydrogel (pAMPS-Cl/AuNR@HA-DA) based on gold nanorods (AuNR) and N -halamine (pAMPS-Cl) with significant photothermal antibacterial properties was developed. The obtained pAMPS-Cl/AuNR@HA-DA hydrogel showed a sponge-like structure with excellent injectability, self-healing, tissue adhesion, and good hemocompatibility. In addition, the hydrogel exhibited excellent in vitro antibacterial capacity under near-infrared (NIR) laser irradiation through the synergistic action of photothermal therapy (PTT) and chemical release therapy. It also showed an excellent ability to eliminate bacterial infection and promote wound healing, indicating that the pAMPS-Cl/AuNR@HA-DA composite hydrogel could be a promising dressing for the treatment of skin wounds.

A simple benzopyran-based fluorescence probe DCA-Apa detection of volatile amine has been synthesized. DCA-Apa can recognize volatile amines by dual channel mode (changing from blue to light yellow in sunlight, and from weak pink to orange under 365 nm) in pure water system. DCA-Apa has the advantages of ultra-fast response (∼6 s), NIR emission (655 nm), and a good fluorescence response for many amines. The sensing label or gel loaded with DCA-Apa was prepared by the dipping or mixing method using filter paper or gelatin as solid carriers, which can identify volatile amine vapor and monitor the freshness of salmon by colorimetric and fluorescent dual channels. When the color of the label changes to light yellow-green or the fluorescence of the label becomes orange fluorescence (365 nm UV lamp), it indicates that the fish has rotted. The two-channel method makes up for the deficiency of the single colorimetric method, and establishes a theoretical foundation for more precise assessment of fish freshness., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Abnormal lipid metabolism plays an important role in cancer development. In this study, nontargeted lipidomic study on 230 tissue specimens from 79 nonsmall cell lung cancer (NSCLC) patients was conducted using ultraperformance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS). Downregulation of sphingosine and medium-long-chain ceramides and short-medium-chain acylcarnitine, upregulation of long-chain acylcarnitine C20:0, and enhanced histamine methylation were revealed in NSCLC tissues. Compared with paired noncancerous tissues, adenocarcinoma (AC) tissues had significantly decreased levels of sphingosine, medium-long-chain ceramides (Cer d18:1/12:0 and Cer d16:1/14:0, Cer d18:0/16:0, Cer d18:1/16:0, Cer d18:2/16:0, Cer d18:2/18:0), short-medium-chain (C2-C16) acylcarnitines, LPC 20:0 and LPC 22:1, and significantly increased levels of the long-chain acylcarnitine C20:0, LPC 16:0, LPC P-16:0, LPC 20:1, LPC 20:2, glyceroPC, LPE 16:0, and LPE 18:2. In squamous cell carcinoma (SCC) tissues, sphingosine, Cer d18:2/16:0 and Cer d18:2/18:0, and short-medium-chain acylcarnitines had significantly lower levels, while long-chain acylcarnitines (C20:0, and C22:0 or C22:0 M), LPC 20:1, LPC 20:2, and N1,N12-diacetylspermine had significantly higher levels compared to controls. In AC and SCC tissues, the levels of LPG 18:0, LPG 18:1, and LPS 18:1 were significantly decreased, while the levels of ceramide-1-phosphate (C1P) d18:0/3:0 or LPE P-16:0, N1-acetylspermidine, and 1-methylhistamine were significantly increased than controls. Furthermore, an orthogonal partial least-squares-discriminant analysis (OPLS-DA) model based on a 4-lipid panel was established, showing good discrimination ability between cancerous and noncancerous tissues.

The most common precursors to synthetic glycoproteins are reducing end glycosyl amines. To afford these amines, a carbohydrate is reacted with an excess of an ammonia source to yield the β-anomer, exclusively, in a reaction known as the Kochetkov amination. Although this process is the state-of-the-art method to synthesize non-functionalized, β-amino (βA) glycans, misconceptions surrounding the stability of these amines has limited their use in subsequent reactions. Here, we investigated the stability of seven amino sugars in the neutral, acidic, and basic conditions they would be subject to in common reactions using amines. In neutral and basic conditions, the amino sugars proved relatively stable with the fastest time to 50% hydrolysis being four days for only one carbohydrate. However, acidic conditions promoted rapid hydrolysis, with all amino sugars reaching over 97% hydrolysis within 2 h. Finally, we performed a bioconjugation using fluorescein isothiocyanate and βA-difucosyllactose, revealing sufficient stability of the amino product for a successful subsequent reaction., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

This study comprehensively explored the helix-stabilizing effects of amine-bearing hydrocarbon cross-links (ABXs), revealing their context-dependent nature influenced by various structural parameters. Notably, we identified a 9-atom ABX as a robust helix stabilizer, showcasing versatile synthetic adaptability while preserving peptide water solubility. Future investigations are imperative to fully exploit this system's potential and enrich our chemical toolkit for designing innovative peptide-based biomolecules., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The present study focuses on the development of environmentally friendly bio-composite films using poly(lactic acid) (PLA) as a biopolymer matrix. This is achieved by incorporating amine functionalized green mesoporous silica (GMS) and employing a solution casting method for film fabrication. The motivation behind the work is to improve the compatibility between PLA and green mesoporous silica sourced from rice husk by functionalizing GMS with APTES (3-Aminopropyltriethoxy silane). The primary objective is to explore how the inclusion of GMS influences both the physicochemical attributes and the efficacy of active food packaging in PLA. The introduction of GMS to the PLA matrix not only improves the flexibility of PLA/GMS composite films but also enhances their overall performance. The reinforcement of GMS in the PLA matrix has also significantly contributed towards the reduction in oxygen transmittance rate and provided an anti-bacterial effect towards pathogen i.e. S. aureus and E. coli. The PLA/GMS composite films exhibit antioxidant activity acting as potential scavengers with around 78 % efficacy against DPPH (2,2-diphenyl-1-picrylhydrazyl). Consequently, the PLA/GMS composite formulation proposed in this study shows promising outcomes in terms of strength, flexibility, antioxidant properties, and antibacterial characteristics. Also, the PLA/GMS films extended the shelf life of cut apple samples for seven days., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Biomass-based slow-release fertilizers (SRFs) are a sustainable solution for addressing food scarcity, improving fertilizer efficiency, and reducing pollution, whereas they still face complex preparation, high costs, and low release characteristics. This study introduces a simple and innovative approach to producing bifunctional green SRFs with controlled release and conditioning properties for saline soils and harsh environments. The method involves a one-pot preparation of microsphere-structured amine-modified lignin slow-release fertilizer (L-U X ) using biomass lignin as the starting material. The L-U X demonstrates an exceptional fertilizer loading rate (66.2 %) and extended slow-release performance (288 h), effectively enhancing the fertilizer's release ability. Compared to traditional fertilizers, the bifunctional L-U X significantly improves soil water retention capacity (824.3 %), plant growth, and germination percentage in challenging soil conditions (133 %). These findings highlight the potential of L-U X as a large-scale controlled-release fertilizer in harsh environments. A life cycle assessment (LCA) was also conducted to evaluate the environmental impact of L-U X from its production to disposal. This revealed that L-U X has a minimal environmental footprint compared to conventional inorganic fertilizers. This study further supports the widespread application of L-U X as an environmentally friendly alternative., Competing Interests: Declaration of competing interest The authors declare no competing financial interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Bis(benzimidazol-2-yl)amine scaffold is not present in dipeptidyl peptidase-4 (DPP-4) inhibitors published so far. Herein, the inhibitory potential of bis(benzimidazol-2-yl)amine derivatives against DPP-4 was evaluated. In non-competitive inhibition mode, three representatives 5, 6, and 7 inhibited DPP-4 in vitro with IC 50 values below 50 μM. The assessed binding pocket of DPP-4 for these benzimidazoles includes the S2 extensive subsite's residues Phe357 and Arg358. None of the lead compounds showed cytotoxicity to human neuroblastoma SH-SY5Y cells at concentrations lower than 10 μM. None showed significant binding affinity at dopamine D 2 , D 3, and histamine H 1 , H 3 receptors, at concentrations lower than 10 μM, leading to preferable outcomes due to mutually opposite effects of these neurotransmitters on each other. The potential beneficial effects on dopamine synthesis and the survival of dopaminergic neurons could be mediated by DPP-4 inhibition. These effective noncompetitive DPP-4 inhibitors, with inhibitory potential better than reference diprotin A (relative inhibitory potency compared to diprotin A is 3.39 and 1.54 for compounds 7 and 5, respectively), with the absence of cytotoxicity to SH-SY5Y cells, are valuable candidates for further evaluation for the treatment of diabetes and associated disruption of neuronal homeostasis., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

The design and fabrication of synergistic hybrid antibacterial materials is a promising approach for achieving effective sterilization while compensating for the deficiency of a single component. Despite being highly effective biocidal components, the poor UV light stability of some N-halamines limits their applications. This study was conducted to address this issue by the rational integration of cyclic N-halamine precursor (PGHAPA) with microwaved zinc oxide (MWPPy-ZnO) nanoparticles via covalent bonds and the preparation of cellulose nanofibrils based antibacterial composite films after chlorination (CNF/MWPPy-ZnO-PGHAPA-Cl). The proposed films offered tight lamellar structure, considerable thermal stability and better mechanical properties. The results from the FT-IR and XPS experiments provided the evidence of chemical reactions among the PGHAPA, MWPPy-ZnO, and CNF film. Notably, the CNF/MWPPy-ZnO-PGHAPA-Cl films showed improved UV stability with a chlorine content of up to 0.16 % after 24 h of irradiation, which was much greater than that of the CNF/PGHAPA-Cl films. Furthermore, the CNF/MWPPy-ZnO-PGHAPA-Cl films displayed rapid bactericidal activity, inactivating all the contacted Staphylococcus aureus and Escherichia coli O157:H7 strains within 5 min, along with prominent biofilm disruption, indicating great potential for daily food packaging applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

High-throughput synthesis and screening of chemical libraries play pivotal roles in drug discovery. Click chemistry has emerged as a powerful strategy for constructing highly modular chemical libraries. However, the development of new click reactions and unlocking new clickable building blocks remain exceedingly challenging. Herein, we describe a double-click strategy that enables the sequential ligations of widely available carboxylic acids and amines with fluorosulfuryl isocyanate (FSO 2 NCO) via a modular amidation/SuFEx (sulfur-fluoride exchange) process. This method provides facile access to chemical libraries of N-fluorosulfonyl amides (RCONHSO 2 F) and N-acylsulfamides (RCONHSO 2 NR'R'') in near-quantitative yields under simple and practical conditions. The robustness and efficiency of this double click strategy is showcased by the facile construction of chemical libraries in 96-well microtiter plates from a large number of carboxylic acids and amines. Preliminary biological activity screening reveals that some compounds exhibit high antimicrobial activities against Gram-positive bacterium S. aureus and drug-resistant MRSA (MIC up to 6.25 μg ⋅ mL -1 ). These results provide compelling evidence for the potential application of modular click chemistry library as an enabling technology in high-throughput medicinal chemistry., (© 2024 Wiley-VCH GmbH.)

Efficient and reliable technologies for the on-site detection of illicit drugs are important in drug-facilitated crime investigations. However, the development of such technologies is challenging. Based on the synthetic optimization, introducing a boron ester functional group to the two furanic indicators endows the stimulus-responsive properties synergistically. The ring-opening reaction of the indicators in the presence of amine-containing illicit drugs generated well-known donor-acceptor Stenhouse adducts, accompanied by strong color changes. A small-size and lightweight laminated sensor was integrated based on the outstanding ratiometric variations of the two active furanic indicators. A prototype platform was fabricated equipped with a circuit control, a mini pump, and a signal processing system. A user-friendly detection and efficient screening of amine-containing illicit drugs, including phenethylamines, amphetamines, cathinones, and tryptamines in the liquid states were conducted. The ratiometric response of the sensor was linear in the concentration range of 2.1-10.6 μg·mL -1 for methamphetamine·HCl and methcathinone ·HCl. The detection limits for the two illicit drugs at the sublevel (ng·mL -1 ) were found to be 8.4 and 9.0 ng·mL -1 , respectively. Double-blind field tests and different illicit drugs were evaluated with good screening capability. Successful trials showed the potential applications of the developed prototype platform for efficient and on-site analytical determination.

An amino functionalized paper-based material that utilized amino functionalized polymer particles as sensing probes and adsorption sites was fabricated via internal sizing technology for application in formaldehyde detection and adsorption. A large specific surface area and the porous structure of the paper fibers enable the application of the composite paper-based material as a sensor at low concentrations of primary amine groups. The material reacts with low levels of formaldehyde, resulting in a concentration-based change in the pH, which is rapidly expressed as a color change. After exposure to formaldehyde (0.02 mg/m 3 ) for 10 min, the color of the composite paper-based material changed from pink to brown, demonstrating the high sensitivity of the material, and this transition could be clearly observed using the naked eye. Additionally, the composite paper-based material acts as an adsorbent at a high content of amino groups, owing to a rapid addition reaction with formaldehyde, exhibiting a high adsorption capacity. Considering the high sensitivity, adsorption capacity, and adsorption speed for formaldehyde, the as-developed composite paper-based material exhibits promising application potential in the field of formaldehyde detection and adsorption.

Gamma-aminobutyric acid (GABA) derivatives are a class of effective inhibitory neurotransmitters for treating neurodegenerative diseases, with an immense market demand. Chemical methods are currently the main synthetic strategies for GABA derivatives, facing challenges such as complex processes, low yields, low atom economy, and environmental burden. In recent years, chemoenzymatic synthesis of GABA derivatives has garnered increasing attention because of the high atom economy, high yields, and environmental friendliness. This article reviews the latest advances in the chemical synthesis and chemoenzymatic synthesis of GABA derivatives. Furthermore, it introduces the progress in the industrial synthesis of representative GABA derivatives such as gabapentin, pregabalin, and brivaracetam and prospects the future development of GABA derivatives.

A library of C-3 functionalized flavones was successfully provided via palladium-catalyzed amino- and aryloxycarbonylation reactions of 3-iodoflavone ( 1 ), under mild conditions. This methodology showed good functional group tolerance using a variety of amines and phenols, under an atmospheric pressure of carbon monoxide as a carbonyl source. While the flavone-3-carboxamides ( 2a-t ) were produced in 22-79%, the flavone-3-carboxylates ( 4a'-l' ) were obtained in excellent yields (up to 88%), under identical reaction conditions, just by switching N -nucleophiles to O -nucleophiles. The convenient availability of the involved starting materials confers simplicity to this approach to design new C-3-substituted flavones of biological relevance. The solid-state structures of flavone-3-carboxamide ( 2r ) and flavone-3-ester ( 4f' ) were further studied by single-crystal XRD analysis.

Strategically designed, heteroatom-rich surface functionalized blue fluorescent carbon dots (CDs) were synthesized for high-throughput detection of folic acid (vitamin B9). The highly stable CDs could particularly detect vitamin B9 in the presence of 35 analytes, even up to 40 nM of the vitamin. The versatile CDs were found to have a high affinity for folic acid in wastewater, folic acid tablets, and food samples enriched with folic acid. The hemocompatibility of the CDs was also studied by using a hemolysis assay, confirming the CDs to be nontoxic to human blood samples up to 400 μg/mL. The CDs were then covalently conjugated to biotin, which possesses receptors that are overexpressed in tumor cells. The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide dye) assay and confocal bioimaging studies proved the biotin-modified CDs (CDBT) were remarkably nontoxic in healthy cell lines (HEK-293) and highly target-specific toward tumor cells (HeLa), including triple-negative breast cancer cells (MDA-MB-231). The cytotoxicity assay of 5-fluorouracil encapsulated CDs (CDBTFu) showed the IC 50 value to be 81 μM in HeLa cells and 185 μM in MDA-MB-231 cells, respectively, and significantly higher in HEK-293 cells (over 300 μM), owing to high specificity toward tumor cells.

The application of biocatalysis has become essential in both academic and industrial domains for the asymmetric synthesis of chiral amines, and it serves as an alternative tool to transition-metal catalysis and complements traditional chemical methods. It relies on the swift expansion of available processes, primarily as a result of advanced tools for enzyme discovery, combined with high-throughput laboratory evolution techniques for optimizing biocatalysts. This concept paper explores the utilization of non-conventional media such as ether-type solvents, deep eutectic solvents, and micellar catalysis to enhance biocatalytic reactions for chiral amine synthesis. Each section focuses on the unique properties of these media, including their ability to stabilize enzymes, alter substrate solubility, and modulate enzyme selectivity. The paper aims to provide insights into how these innovative media can overcome traditional limitations, offering new avenues for sustainable and efficient chiral amine production through biocatalytic processes., (© 2024 The Author(s). Chemistry - A European Journal published by Wiley-VCH GmbH.)

Oligoamines in cellular metabolism carry extremely diverse biological functions (i.e., regulating Ca 2+ -influx, neuronal nitric oxide synthase, membrane potential, Na + , K + -ATPase activity in synaptosomes, etc.). Furthermore, they also act as longevity agents and have a determinative role in autophagy, cell growth, proliferation, and death, while oligoamines dysregulation is a key in a variety of cancers. However, many of their mechanisms of actions have just begun to be understood. In addition to the numerous biosensing methods, only a very few simple small molecule-based tests are available for their selective but reversible tracking or fluorescent labeling. Motivated by this, we present herein a new fluorescent bis(acridino)-crown ether as a sensor molecule for biogenic oligoamines. The sensor molecule can selectively distinguish oligoamines from aliphatic mono- and diamino-analogues, while showing a reversible 1:2 (host:guest) complexation with a stepwise binding process accompanied by a turn-on fluorescence response. Both computational simulations on molecular docking and regression methods on titration experiments were carried out to reveal the oligoamine-recognition properties of the sensor molecule. The new fluorescent chemosensor molecule has a high potential for molecular-level functional studies on the oligoamine systems in cell processes (cellular uptake, transport, progression in cancers, etc.).

Multienzyme cascades (MECs) have gained much attention in synthetic chemistry but remain far from being a reliable synthetic tool. Here we report a four-enzyme cascade comprising a cofactor-independent and a cofactor self-sustaining bienzymatic modules for the enantioselective benzylic C-H amination of arylalkanes, a challenging transformation from bulk chemicals to high value-added chiral amines. The two modules were subsequently optimized by enzyme co-immobilization with microenvironmental tuning, and finally integrated in a gas-liquid segmented flow system, resulting in simultaneous improvements in enzyme performance, mass transfer, system compatibility, and productivity. The flow system enabled continuous C-H amination of arylalkanes (up to 100 mM) utilizing the sole cofactor NADH (0.5 mM) in >90 % conversion, achieving a high space-time yield (STY) of 3.6 g ⋅ L -1  ⋅ h -1 , which is a 90-fold increase over the highest value previously reported., (© 2024 Wiley-VCH GmbH.)

Small molecular kinase inhibitors play a key role in modern cancer therapy. Protein kinases are essential mediators in the growth and progression of cancerous tumors, rendering involved kinases an increasingly important target for therapy. However, kinase inhibitors are almost insoluble in water because of their hydrophobic aromatic nature, often lowering their availability and pharmacological efficacy. Direct drug functionalization with polar groups represents a simple strategy to improve the drug solubility, availability, and performance. Here, we present a strategy to functionalize secondary amines with oligoethylene glycol (OEG) phosphate using a one-pot synthesis in three exemplary kinase inhibiting drugs Ceritinib, Crizotinib, and Palbociclib. These OEG-prodrug conjugates demonstrate superior solubility in water compared to the native drugs, with the solubility increasing up to 190-fold. The kinase inhibition potential is only slightly decreased for the conjugates compared to the native drugs. We further show pH dependent hydrolysis of the OEG-prodrugs which releases the native drug. We observe a slow release at pH 3, while the conjugates remain stable over 96 h under physiological conditions (pH 7.4). Using confocal microscopy, we verify improved cell uptake of the drug-OEG conjugates into the cytoplasm of HeLa cells, further supporting our universal solubility approach., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

In this work, an easy, safe, simple, and efficient pH-switchable deep eutectic solvents (DESs)-based liquid phase microextraction followed by high-performance liquid chromatography-diode array detector analysis was developed for the determination of 1,3-dimethylamylamine (DMAA). The switchability of the obtained DESs was investigated by changing the pH. Then the best-selected DES was characterized and the application of the selected DES in the extraction of DMAA from sports nutrition and bodybuilding supplements was investigated. The DES synthesized from l-menthol: oleic acid in a molar ratio of 1:2 had the highest efficiency in the extraction of the target compound. Under the optimum conditions, (50 µL of DES, 100 µL of 4 mol/L KOH, 100 µL of 4 mol/L HCl, extraction time of 40 s and without salt addition) the calibration graph was linear in the range of 0.05-100 µg/kg and limit of detection was 0.02 µg/kg. The relative standard deviations including intra-day and inter-day for 10.0 µg/kg of DMAA in real samples were 2.7% (n = 7) and 5.3% (n = 7), respectively. The enrichment factor and percentage extraction recovery of the method were 283 and 85%, respectively. The relative recoveries for DMAA in different samples were in the range of 90%-109%., (© 2024 Wiley‐VCH GmbH.)

The development of multi-stimuli-responsive (MSR) materials is a tempting yet intriguing challenge due to the absence of a defined design approach. In this study, we designed and synthesised two compounds based on triphenylamine, namely, TPA-Tz1 and TPA-Tz2. The photoluminescent investigations reveal the MSR behaviour of both compounds. TPA-Tz1 shows reversible mechanochromism with a blue-shifted emission due to changes in intermolecular interactions. Furthermore, both compounds exhibit solvatochromism in solvents of varying polarity. Detailed studies suggest that solvatochromism in TPA-Tz1 can be attributed to twisted intramolecular charge transfer (TICT), while in TPA-Tz2, it is due to intramolecular charge transfer (ICT). Additionally, both compounds display acidochromic properties in solution as well as in the solid state due to the protonation of the triazole ring. All changes in emissions are corroborated through theoretical calculations. The results provide insights into the intricate interplay of molecular interactions and structural rearrangements that contribute to the compound's multifaceted responsiveness., (© 2024 John Wiley & Sons Ltd.)

Perovskite nanocrystals (PNCs) have emerged as promising candidates for fluorescent probes owing to their outstanding photoelectric properties. However, the conventional CsPbBr 3 (CPB) NCs are extremely unstable in water, which has seriously limited their sensing applications in water environment. Herein, we present a powerful ligand engineering strategy for fabricating highly water-stable CPB NCs by using a biopolymer of wool keratin (WK) as the passivator and the polyaryl polymethylene isocyanate (PAPI) as the cross-linking agent. In particular, WK with multi-functional groups can serve as a polydentate ligand to firmly passivate CPB NCs by the ligand exchange process in hot toluene; and then the addition of PAPI can further encapsulate CPB NCs by the crosslinking reaction between PAPI and WK. Consequently, the as-prepared CPB/WK-PAPI NCs can maintain ∼ 80 % of their relative photoluminescence (PL) intensity after 60 days in water, and they still maintain ∼ 40 % of their relative PL intensity even after 512 days in the same environment, which is one of the best water stabilities compared previously reported polymer passivation methods. As a proof-of their application, the portable CPB/WK-PAPI NCs-based test strips are further developed as a fluorescent nanoprobe for real-time and visual monitoring amines and food freshness. Among various amine analytes, the as-prepared test strips exhibit higher sensitivity towards conjugated amines, achieving a remarkable detection limit of 18.3 nM for pyrrole. Our research not only introduces an innovative strategy involving natural biopolymers to enhance the water stability of PNCs, but also highlights the promising potential of PNCs for visually and portably detecting amines and assessing food freshness., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

A novel analytical strategy was proposed to simultaneously quantify two advanced glycation end products (AGEs) including N ε -(Carboxymethyl)lysine (CML), N ε -(Carboxyethyl)lysine (CEL) and eight heterocyclic amines (HAs) including IQ, MeIQ, MeIQx, 4,8-DiMeIQx, 7,8-DiMeIQx, PhIP, Harman, and Norharman. The procedure was based on a two-step extraction, solid phase extraction (SPE) purification followed by ultra performance liquid chromatography tandem mass spectrometry. The established method showed a good linearity (R 2  ≥ 0.9950), rapid processing time (8 min per sample), satisfactory recoveries (matrix spiked recoveries range from 72.2% to 119.6%) and precision (intra-day and inter-day RSDs were <19.3%). The limit of quantification (LOQ) and limit of detection (LOD) resulted to be between 0.05-15 ng/g and 0.2-50 ng/g, respectively. The validated technique was further applied to determine HAs and AGEs in eight stewed meat product samples consumed in Shanghai, with the amount of HAs and AGEs ranging from 2.851 to 18.289 ng/g and 118.158-543.493 ng/g, respectively., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Glycolipids incorporating positive charges, mediated by an imidazolium cation, have shown potential for effective formulation of vesicular drug carriers, reflecting repulsive electrostatic forces, promoting the formation of nanosized assemblies and preventing unwanted Oswald ripening (Goh et al. (2019), ACS Omega 4, 17,039). Our continuous development of an assembly-based drug delivery system prompted us to investigate a pH-sensitive analogue, leading to the synthesis of a 6-amino-Guerbet glycoside. However, in contrast to the imidazolium counterpart, the amine-mediated charge increased the intermolecular cohesions, furnishing bigger assemblies instead, which further increased upon introduction of acid. Moreover, assemblies exhibited a significantly reduced positive charge density. It is concluded that strong proton-initiated hydrogen bonding between amino groups provide cohesive head group interactions overcompensating possible repulsive charge interactions. While this behavior invalidates the application of the amino-glucoside as dispersing agent for the formulation of small vesicles, it potentially paves a route towards enhanced vesicle stability., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Thorsten Heidelberg reports financial support was provided by PETRONAS Research Sdn Bhd. Thorsten Heidelberg has patent A FUNCTIONALIZED GLYCOLIPID AND AN APPLICATION THEREOF pending to Universiti Malaya. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Heterocyclic aromatic amines (HAAs) are harmful byproducts in food heating. Therefore, exploring the prediction and generation patterns of HAAs is of great significance. In this study, genetic algorithm (GA) and support vector regression (SVR) are used to establish a prediction model of HAAs based on heating conditions, reveal the influence of heating temperature and time on the precursor and formation of HAAs in roast beef, and study the formation rules of HAAs under different processing conditions. Principal component analysis (PCA) showed that the effect on HAAs generation increases with the increase of heating temperature and time. The GA-SVR model exhibited near-zero absolute errors and regression correlation coefficients (R) close to 1 when predicting HAAs contents. The GA-SVR model can be applied for real-time monitoring of HAAs in grilled beef, providing technical support for controlling hazardous substances and intelligent processing of heat-processed meat products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal connections that could influence the work reported in this article., (Copyright © 2024. Published by Elsevier Ltd.)

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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Various strategies are being explored to reduce the formation of undesirable compounds during the thermal processing of foods. This study investigates the impact of incorporating annatto seed powder (Bixa orellana L.) into beef patties to reduce the formation of heterocyclic amines (HAs) during charcoal-grilling and pan-frying. A three-level full factorial design was used to assess the effect of both annatto seed powder concentration and cooking times on HAs formation. The results showed that HA formation increased with longer cooking times and decreased with higher concentrations of annatto seed powder. A significant reduction in HA content was observed in both charcoal-grilled and pan-fried beef patties when annatto seed powder was added, with a particularly notable 91 % reduction at the 1 % addition level. These findings demonstrate that the addition of annatto seed powder is a highly effective strategy for reducing HA formation in beef patties. CHEMICAL COMPOUNDS STUDIED IN THIS ARTICLE: 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) (PubChem CID: 62275); 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx) (PubChem CID: 104739); 2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline (7,8-DiMeIQx) (PubChem CID: 104855); 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) (PubChem CID: 1530); 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) (PubChem CID: 5284474); 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2) (PubChem CID: 5284476); 2-amino-9H-pyrido[2,3-b]indole (AαC) (PubChem CID: 62805); 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeAαC) (PubChem CID: 62244); Bixin (PubChem CID: 5281226)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

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 m 2 /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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Seafood plays a major role in the human diet. During transportation, without proper storage and supply chain, its quality deteriorates easily. The post-harvesting processes such as the storage of food play a crucial role in human health. So it is highly imperative to have a technique for identifying food spoilage earlier to ensure the food safety and security of the consumers. Herein we have developed a highly selective and sensitive fluorescent 'Turn-on' probe 2-amino-5-nitrobenzo [d] thiazol-2-yl) imino)methylphenol ANT based on aggregation induced emission (AIE). ANT molecule possesses both restricted intramolecular rotation (RIR) and excited state intramolecular proton transfer (ESIPT) properties leading to fluorescent enhancement rather than aggregation caused quenching (ACQ). The probe shows high selectivity and sensitivity towards the NH 3 vapor. This probe with the AIE property is employed for the real-time detection of NH 3 in both aqueous and gaseous phases. ANT molecule is deposited on the paper shred by a physical method is utilized to monitor NH 3 vapor from red snapper fish as a real-time sample during its degradation processes. After two days there is a ratiometric color change in the paper shred from yellow to orange for the fish stored at room temperature indicating its rotten and unpalatability nature. Paper shred is reused by immersing it into the tetrahydrofuran (THF), in which it retains its initial color due to deprotonation of NH 3 , keto to enol tautomerism discloses the reusability of the fluorescent probe. Studies carried out using UV-visible and fluorescence spectroscopy infer that the ANT probe has high affinity towards NH 3 vapor., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)