Toxic Reagents Research Articles

FlowDiff: a simple, flow cytometry-based approach for performing a leukocyte differential count.

To overcome the challenges of a manual leukocyte differential count, we have developed FlowDiff, an 8-colour, single tube flow cytometry panel, and investigated whether it could potentially replace the manual differential in our laboratory. The instrument was set up in accordance with the EuroFlow settings, and the protocol comprised a stain-lyse no wash process, taking approximately 30 min of working time, without the addition of a toxic lysis reagent. We found a very good correlation for all leukocyte populations between FlowDiff and the Sysmex XN analyzer in 80 normal, non-flagged samples. In addition, FlowDiff showed a very good correlation with manual differential in 168 abnormal samples, as well as a high diagnostic accuracy. FlowDiff correctly identified all samples with acute leukemia (N = 13) and differentiated all B-lymphomas (N = 49) in samples with lymphocytosis. Moreover, FlowDiff detected an additional five samples with B-lymphocytosis without any prior hematological malignancy, which turned out to be a B-lymphoma. Our data suggest that FlowDiff, our 8-colour flow cytometry-based differential, is comparable to, and can successfully substitute the manual differential.

Multifunctional Dual Nano-MOF-Modified Decellularized Small Intestinal Submucosa Membrane Accelerates Healing of Infected Wound.

The treatment of complex or chronic skin wounds caused by burns, trauma, surgery, and genetic disorders has been a worldwide challenge. Small intestinal submucosa (SIS) is a biological material that is widely used in wound healing. How to further expand the wound healing application of SIS, especially in repairing infected wounds, remains a hot research topic for many tissue engineering and biomaterial scholars focusing on skin regeneration. This study uses nanometal-organic frameworks (nano-MOFs), which have not been applied to modify the SIS membrane before, to construct multifunctional dual nano-MOFs @ SIS membrane (dnMOF@SISm). Nano-MOFs are functionalized onto the nanofiber of SIS via in situ self-assembly under mild reaction conditions without any toxic reagent or complex instruments. The dnMOF@SISm can release Co2+, Zn2+, and bioactive factors, participating in the whole stage of the repair of infected wounds. In vitro, it can regulate the biological activities of various functional cells such as fibroblasts, endothelial cells, and macrophages and shows good antibacterial ability. In the infected full-thickness skin defect rat model, dnMOF@SISm can release metal ions and ligands, killing pathogenic bacteria colonized on the wound surface at the first stage, and then trigger and accelerate the skin repair process via angiogenesis, immune regulation, and collagen deposition. Above all, an efficient, nontoxic, mild self-assembly strategy realizes the functionalization of dual nano-MOFs on the nanofiber of SIS to expand its clinical application scenarios, especially in infected wounds.

Rapid Synthesis of Non-Toxic, Water-Stable Carbon Dots Using Microwave Irradiation

Carbon dots (C-Dots) have garnered significant attention in various fields, including biomedical applications, photocatalysis, sensing, and optoelectronics, due to their high luminescence, biocompatibility, and ease of functionalization. However, concerns regarding their potential toxicity persist. Conventional synthesis methods for C-Dots often require long reaction times, high pressures, expensive equipment, extreme temperatures, and toxic reagents. In contrast, microwave irradiation provides a rapid, cost-effective, and scalable alternative for the synthesis of high-quality C-Dots. In this study, we report the single-step, 3-min synthesis of water-stable carbon dots at 100 °C, 120 °C, and 140 °C using microwave irradiation. Particle stability was achieved through polyethyleneimine (PEI) functionalization. The toxicity of the synthesized carbon dots was evaluated in marine crustaceans, revealing that C-Dots with an estimated size below 10 nm did not exhibit toxicity after 24 and 48 h of exposure. These findings demonstrate the potential of microwave-synthesized carbon dots as non-toxic, water-stable nanomaterials for environmental and biomedical applications.

Preparation of tannic acid-based recyclable adhesive with high adhesion property, low curing temperature, and environmental tolerance

Tannin-based adhesives have demonstrated promise in decreasing dependence on petrochemical resources linked to formaldehyde-based resins. However, current tannin-based adhesives face challenges due to the incorporation of expensive or toxic reagents such as isocyanate, epoxy, and formaldehyde, as well as the inability to be recycled. This study presents a simple and eco-friendly approach for producing a tannic acid-based recyclable adhesive (TA-BVB) by employing tannic acid and 1,4-butanediol divinyl ether through acetal reactions. The resulting adhesive can be cured at a low temperature of 70℃ and demonstrated high bonding strength on wood and aluminum sheets, measuring 4.45 MPa and 5.44 MPa, respectively. Notably, the adhesive maintained its adhesion strength even under harsh conditions, including high temperatures (100℃), liquid nitrogen (-196℃), and exposure to various solvents. Moreover, the adhesive showcased excellent reusability, retaining over 100 % and 86 % of bonding strength after the first and second rounds of hot pressing, respectively. This adhesive can be repaired using infrared laser irradiation and displayed remarkable mold resistance. This research underscores the potential of tannic acid in developing environmentally friendly, high-performance, recyclable adhesives with versatile applications.

Engineering of self-assembled silver-peptide colloidal nanohybrids with enhanced biocompatibility and antibacterial activity

Several bacterial strains have developed resistance against commercial antibiotics, and interestingly, supramolecular nanomaterials have shown considerable advantages for antibacterial applications. However, the main challenges in adopting nanotechnology for antibacterial studies are random aggregation, compromised toxicity, multi-step preparation approaches, and unclear structure-function properties. Herein, we designed the amphiphilic tripeptide that acts as a reducing and capping agent for silver metal to form silver-peptide colloidal nanohybrids with the mild assistance of UV light (254 nm) through the photochemical reduction method. The nanohybrids are characterized by different spectroscopic and microscopic techniques, and non-covalent molecular interactions between metal and peptide building blocks confirm their central role in the formation of nanohybrids. The tripeptide is biocompatible and can reduce the toxicity of silver ions (Ag+) by reducing to Ag0. These colloidal nanohybrids showed antibacterial activity against gram-negative and gram-positive bacterial strains, and the possible mechanism of killing bacterial cells could be membrane disruption. This synthetic strategy is facile and green, which helps avoid using toxic chemicals or reagents and complicated methods for colloidal nanohybrid preparation for biomedical applications.

Development of a Spectrophotometric Flow-Based System for the Determination of Total Polyphenol Content in Legume Flours.

Conventional nutritional characterization of legume flours comprises costly and laborious analytical methods for nutrient quantification that establish the quality of seeds, including their macronutrient quantification, fiber, mineral, antioxidant content, and more. The quantification of total polyphenol content (TPC) in legumes is performed using different analytic methods, namely the Folin-Ciocalteu (FC) method, which is lengthy and employs potentially toxic reagents. Additionally, it is time-consuming and prone to human error if carried out in a conventional batch mode. To develop a semi-automatic method for a faster, greener, and more precise TPC quantification, resorting to flow injection analysis (FIA). The development of the FIA method was based on the FC method. The flow manifold was structured by performing an array of preliminary studies, which led to the establishment of the method that displayed the highest sensitivity (highest slope of the calibration curve). The method was applied to determine the TPC in various legume flours. This novel method resulted in a throughput of 1 analysis per minute, allowing to analyze 20 samples in triplicate within an hour, with a LOD of 4.32 mg L-1, a LOQ of 14.4 mg L-1, and an RSD of 4.4%. The results calculated from the proposed FIA method agreed with those of the reference procedure. By using the FIA system, a lower consumption of reagents was observed. Additionally, as there is no need to reach chemical equilibrium, a high throughput has been achieved, resulting in a faster and greener method for the determination of polyphenols in various types of legumes.

Ultrasonic Production of Chitosan Nanoparticles and Their Application Against Colletotrichum gloeosporioides Present in the Ataulfo Mango.

In Mexico, the Ataulfo mango crop faces significant challenges due to anthracnose, a disease caused by the fungus Colletotrichum gloeosporioides. The need to use eco-friendly fungicides is crucial to avoid the use of harmful synthetic chemicals. This study aimed to prepare chitosan nanoparticles through a simple and effective ultrasound-assisted top-down method, with high antifungal efficiency. The nanoparticles were prepared from chitosan (DD = 85%, MW = 553 kDa) and Tween 20 under constant sonication. The formation of the nanoparticles was initially confirmed by Fourier-transform infrared (FTIR) spectroscopy; and their physicochemical properties were subsequently characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The antifungal potential of the chitosan nanoparticles against the phytopathogen Colletotrichum gloeosporioides was evaluated with isolated fungi obtained directly from mango tissues showing anthracnose symptoms in the state of Guerrero, Mexico. The fungus was identified through SEM imaging, showing a regular and smooth conidial layer, with cylindrical shape (r = 2 µm, h = 10 µm). In vitro tests were conducted with three different concentrations of chitosan nanoparticles to assess their inhibitory effects. After seven days of incubation, a maximum inhibition rate of 97% was observed with the 0.5% nanoparticle solution, corresponding to a fungal growth rate of 0.008 cm/h. At this time, the control mycelial growth was 7 cm, while the treated sample reached a radius of 0.55 mm. These results demonstrated the antifungal effect of the nanoparticles on the membrane and cell wall of the fungus, suggesting that their composition could induce a resistance response. The inhibitory effect was also influenced by the particle size (30 nm), as the small size facilitated penetration into fungal cells. Consequently, the parent compound could be formulated and applied as a natural antifungal agent in nanoparticle form to enhance its activity. The method described in this study offers a viable alternative for the preparation of chitosan nanoparticles, by avoiding the use of toxic reagents.

Access to Diverse Carbonyl Compounds by Catalyst-Free and Photoinduced Aerobic Cleavage of C=N Bonds.

Functional group interconversion is of great significance in organic synthesis. However, aerobic cleavage of C=N bonds to access carbonyl compounds still suffered from some limitations such as harsh reaction conditions, stoichiometric oxidants, poor substrate scope and use of toxic reagents. Herein, we report a catalyst-free and photo-induced aerobic cleavage of C=N bonds to afford diverse carbonyl compounds using oxygen from air as green oxidant. This mild methodology permits N-tosylhydrazones converted into the corresponding carbonyl compounds including ketones, aldehydes and carboxylic acids, showing broad functional group tolerance and compatibility. Moreover, the gram-scale reaction and post-modification of complicated molecules proved the applicability and efficiency of this strategy. Finally, a plausible mechanism was proposed based on spectroscopic investigations and detailed mechanistic studies.

Efficient solid-phase RNA extraction using carbon nanomaterials

Recent research highlights RNA’s therapeutic potential in nucleic acid-based therapies. However, effective RNA recovery and purification remain challenging due to similar impurities affecting therapeutic outcomes. Traditional RNA isolation methods are often slow, inefficient, and involve toxic reagents. Carbon-based materials offer a promising alternative as adsorbents for nucleic acids due to their excellent mechanical and chemical properties. This study describes an efficient, simple, and cost-effective method for RNA recovery from complex Escherichia coli extracts using carbon materials with different structures and surface modifications. RNA adsorption and desorption screening experiments were performed using different carbon materials. N-doped CNTs (CNT-N-ox) and carbon nanofibers (CNF-ox), both oxidized with HNO3, showed RNA adsorption capacities of 42 % and 55 %, respectively, also allowing effective RNA desorption (81 % and 72 %, respectively). Additionally, the materials demonstrated reusability, maintaining RNA adsorption capacity over four cycles. The selectivity of the materials enabled a simple method to recover RNA free from DNA contamination by performing three consecutive cycles. Moreover, no contaminating protein was found in the recovered sample. The analysis by circular dichroism also revealed that RNA maintained its integrity and stability when recovered from these materials. Overall, the study demonstrates the potential of carbon materials for efficient RNA capture and pre-purification.

Towards More Sustainable Schiff Base Carboxylate Anodes for Sodium-Ion Batteries.

Bismine sodium salt (BSNa), a Schiff base with two sodium carboxylates, has shown promising electrochemical performance as an anode material. However, its synthesis involves toxic reagents and generates impurities, requiring significant solvent use for purification. This study introduces a novel synthetic method using sodium hydroxide as the sole reagent, which acts as both a base and Na source in the ion exchange step. With this procedure, we reduce the amounts of chemicals, diminish toxicity, improve the purity of the target compound, and use less solvent while maintaining comparable electrochemical performance. Additionally, the procedure is carried out under anhydrous conditions that avoid the undesirable hydrolysis of the imine linkages. In a previous report, the processing of the composite electrode was not established. In this article, we address this issue; the electrochemical performance, specifically the rate capability, is enhanced by processing the electrodes in laminate form rather than powder. As alternative to N-methyl-2-pyrrolidone (NMP), a common but disadvantageous solvent in laminate processing, other solvents were explored by testing acetone (DMK), methylisopropylketone (MIPK), and a DMK-NMP mixture. The remarkable electrochemical performance (specific capacity of 260-280 mAh/g, and capacity retentions higher than 84% at 1C (260 mA/g) remained consistent across these solvents. Furthermore, we investigated replacing copper with aluminum as the current collector to reduce costs and increase the energy density of the battery. While aluminum performed comparably to copper at low specific currents C/10 (26 mA/g), it showed a significant shift in the redox process potentials at higher specific currents.

Maillard Type Reaction for Electroless Copper Plating onto Ceramic Nanoparticles

A high demand for oxide dispersion strengthened (ODS) materials arose in wide fields of application. The electroless plating method has been presented as an elegant way to overcome different surface energies and obtain metal‐plated ceramics. However, copper electroless plating is still performed under harsh conditions with toxic and expensive reagents, including noble metals and harsh reducing agents like formaldehyde and hydrazine. To create a pure copper metal matrix in an environmentally friendly and efficient way a previously reported method is advanced in a way that naturally occurring amino acids are utilized. A screening of several amino acids leads to an improvement in phase purity and atomic efficiency. Therefore, a Maillard type reaction with lysine as amino compound is reported to show the best results in the particle coating for all ceramic nanoparticles evaluated. The metal plating results in uniform round micro particles showing a homogeneous coating. In order to obtain copper matrix composites, the prepared particles are successfully implemented in a PBF‐LB/M process after mixing with a highly conductive copper alloy. The resulting products were investigated by transmission electron microscopy, scanning electron microscopy, powder X‐ray diffraction, and optical density measurements.

Polyethylene Glycol-Enzyme Nanocomplexes as Carrier-free Biocatalyst for Pickering Interfacial Catalysis.

PEG-enzyme nanocomplexes are prepared and stabilized in an oil-in-water-type emulsion for Pickering interfacial biocatalysis, and these nanocomplexes function as catalysts and emulsifiers at the emulsion interface. The nanocomplexes are self-assembled by cross-linking mPEG-ALD with lipase, without complicated synthesis steps, toxic chemical reagents, and external carriers. Moreover, the mild cross-linking process preserves the original structure of the enzyme, the retention rate of enzyme activity is 82.1%, and the nanocomplexes are used to emulsify biphasic aqueous-organic solution into Pickering emulsion. The system exhibits excellent reusability, with enzyme activity remaining at 86.05% after five cycles, providing a desirable eco-friendly platform for carrier-free Pickering interfacial biocatalysis.

From Proline to Chlorantraniliprole Mimics: Computer-Aided Design, Simple Preparation, and Excellent Insecticidal Profiles.

Chlorantraniliprole (CHL), a favored agricultural insecticide, is renowned for its high efficiency and broad-spectrum effectiveness against lepidoptera insects. However, the urgency for new insecticide development is underscored by the intricate multistep preparation process and modest overall yields of CHL, along with the escalating challenge of insect resistance. In response, we have crafted CHL mimics from proline employing computer-aided drug design. Molecular docking analysis of CHL's interactions with the ryanodine receptor (RyR) revealed that the nitrogen atom within the pyrazole moiety does not engage in pivotal interactions. Its removal may not abolish bioactivity entirely but could substantially simplify the synthetic process, thereby enhancing atom economy. This revelation prompted the exclusion of nitrogen and the subsequent formation of a pyrrole ring, enabling the meticulous design of synthetic pathways characterized by cost-effective precursors, streamlined synthesis, the avoidance of toxic reagents, minimal instrumentation, and high yields in the pursuit of innovative RyR modulators. Among these modulators, A1 and B1, obtained with yields exceeding 60%, showcased exceptional insecticidal potency, with LC50 values spanning from 0.12 to 1.47 mg L-1 against P. xylostella and M. separate. The inhibitory effects of these two compounds on insect detoxification enzymes imply a reduced likelihood of eliciting resistance in comparison to CHL, a finding further corroborated by their insecticidal potency against resistant pests. Moreover, molecular docking, MD simulations, and DFT calculations provided valuable structural insights, potentially unraveling the superior insecticidal activity of these two molecules, and thus paving the way for developing more potent insecticides.

Fabrication of stable hydrogel microspheres with hydrophobic shell using water-in-water (W/W) Pickering emulsion template

Hydrogel microspheres are promising for food applications. The water-in-oil (W/O) emulsion template is commonly used to prepare the hydrogel microspheres. However, this method often involves synthetic surfactants and toxic organic solvents to remove the oil phase. The swelling problem of the resultant microspheres is another obstacle. In this study the water-in-water (W/W) emulsion template of gelatin-in-dextran was used to prepare the hydrogel microspheres, without the addition of surfactants, toxic reagents and high energy input. To prevent swelling, zein particles modified with alginate were served as a hydrophobic shell of the gelatin core. The formation evolution of these core–shell microspheres and its relevant factors including phase behavior of the immiscible gelatin/dextran, the binding of zein/alginate and the addition of the modified zein particles were investigated. It was found that small amount of alginate could induce zein particles to absorb on the gelatin surface, whereas the excess led to absorption competition. When using 0.6 wt% particles with zein/alginate ratio of 1:0.5, the ideal core–shell microspheres which were fully covered by the particles and with a self-supporting architecture in uniform size (18.8 ± 0.1 μm) and spherical shape were obtained. These microspheres showed remarkable stability under the conditions of heat treatment, varied pHs and salt concentrations and long-term storage either in refrigerator or room environment. Their sizes were easily manipulated by adjusting the concentration and molar mass of the biopolymers. It is believed that the desired stability and tunable sizes of these edible core–shell microspheres could contribute the development of their applications in foods.

At the Speed of Light: Recent Advances on Photocatalyzed Generation and Applications of Iminyl Radicals Promoted by Visible-light

: Nitrogen-positioned radicals are chemical entities that have a lengthier history than carbon ones and their high reactivity makes them invaluable. But, despite its power, much of its chemistry is still uncharted. Currently, developed methodologies to access nitrogen-positioned radicals, such as transition metal catalysis or visible-light photoredox methods through a single-electron transfer process, avoiding the use of harmful or toxic reagents, excess raw materials, solvents as well as pre-functionalization steps or extensive synthetic routes are in continuous progress. This revision aims to depict the recent advances in the field of iminyl-radicals’ syntheses, a special class of radicals placed on nitrogen, catalyzed by transition metals or photoredox techniques for the construction of C-N bonds and their synthetic applications. This work serves as a comprehensive guide for the scope of synthetic applications that this kind of radicals could have.

Production of few-layer graphene and boron nitride nano onions via lamp ablation

Abstract Few-layer graphene, and separately, boron nitride nano onions have been synthesised by a novel lamp ablation method which is a one-step, high-yield process that is catalyst-free, devoid of toxic reagents, with short reaction times, and potentially scalable. The precursor for the few-layer graphene is graphite flake, while that of boron nitride nano onions is hexagonal boron nitride powder. Product nanostructures are characterised by high-resolution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectroscopy (EDS) and electron energy loss spectroscopy (EELS). We also report on our commercialisation trajectory to translate promising research findings in the laboratory to the market. For the few-layer graphene product, it is presently on a pre-commercial pilot plant phase.

Improved interfacial properties of carbon fiber reinforced epoxy resin composite by in‐situ self‐assembled mental‐phenolic networks

AbstractThe chemical modification of carbon fiber surface often uses toxic reagents and harsh reaction conditions, while the preparation process of metal‐phenol networks (MPNs) is simple, rapid, non‐toxic and harmless, which provides a direction for alleviating environmental problems. In this study, tannic acid (TA) was coordinated with Fe3+ to form MPNs, which was coated on the surface of carbon fibers through π‐π interaction. The results indicated that oxygen functionalities on the surface of the MPN coating can facilitate better adhesion between the carbon fiber and the epoxy resin, when the molar ratio of TA to Fe3+ is 1:3 and the pH is 4, the interlaminar shear strength (ILSS) performance of the composite material reaches its optimal level. In addition, a green and non‐destructive method is provided for the surface modification of carbon fiber, which can effectively optimize the interfacial properties of carbon fiber reinforced polymer (CFRP) composites.

Электрохимический синтез замещенных 2-амино-4Н-хромен-3-карбонитрилов на основе кросс-сопряженных диеноновых производных циклогексана и малононитрила

The relevance of research in the field of chemistry of compounds of a number of 2-aminochromen(pyran)-3-carbonitrile is due to their practical significance and numerous transformation possibilities. Over the past two decades, there has been a dynamic development of the electrochemical synthesis of compounds of this series, which is determined by the possibility of eliminating expensive or toxic reagents, conducting reactions at normal temperatures and pressure in electrolyzers of a fairly simple design and other advantages. Based on the efficiency and environmental friendliness of this method, we have for the first time synthesized 2-aminotetrahydro-4H-chromene-3-carbonitriles based on available cross-conjugated dienone derivatives of cyclohexane series and malononitrile under electrolysis conditions (platinum cathode, graphite anode, KBr electrolyte, 80% EtOH). The control over the course of the reaction and the electrochemical behavior of all components has been carried out using cyclic voltammetry. The analysis of the voltammograms made it possible to establish the direct activation of the methylene component at the cathode with the formation of the anion -CH(CN)2. A comparison of the electrochemical synthesis of chromencarbonitriles with the chemical one indicates a significant advantage of electrosynthesis due to the exclusion of a toxic organic catalyst, reduction of reaction time with good yields of products, as well as the possibility of monitoring reactions using cyclic voltammetry, dispersion of products.

Effect of synergistic CeO2/MoS2 abrasives on surface roughness and material removal rate of quartz glass

Cerium oxide (CeO2) is a primary abrasive frequently used in quartz glass polishing slurry for facilitating glass surface planarisation. However, due to its exorbitant synthesis costs and extremely corrosive as well as toxic reagents in the system, the chemical modification of CeO2 abrasives have limited practical applications. In this work, a novel chemical mechanical polishing slurry for quartz glass incorporating potassium oleate (KOL), deionised water (DIW), cerium dioxide and molybdenum disulphide (MoS2) was developed in this paper to enhance the chemical mechanical polishing (CMP) performance of CeO2-based polishing slurry. KOL creates an alkaline environment for the system, further develops silicate insoluble substances on the quartz glass surface and boosts the material removal rate (MRR) in CMP. MoS2 exhibits a two-dimensional layered nanosheet structure between the abrasive and quartz glass, and then acts as a solid lubricant to prevent excessive mechanical damage, thus increasing the abrasive's wettability. This characteristic helps avoid scratches and other defects on the quartz glass surface. Notably, when the content of KOL and MoS2 in the system is 0.2 wt% and 0.3 wt%, respectively, the surface roughness of the quartz glass surface is 0.48 nm under the scanning area of 15 × 15 μm2 and the MRR is 24.03 μm/h following CMP. The synergistic interaction between CeO2 and MoS2 significantly enhances the abrasive performance on the glass substrate, offering a novel approach for developing polishing fluids that leverage the collaborative effects between abrasives and two-dimensional materials.

Fabrication of high-performance graphene fiber: Structural evolution strategy from a two-step green reduction method

Graphene fibers (GFs) have a bright future in a variety of applications ascribing to their excellent performance. However, strict preparation conditions with extremely high graphitization temperature or toxic chemical reagents severely restrict their extensive implementation. Meanwhile, researchers are seeking easily scalable and eco-friendly GFs production methods. Here, we propose a green two-step reduction strategy involving L-ascorbic acid (LAA) chemical reduction followed by low-temperature annealing for the preparation of high-performance GFs. Benefiting from the elimination of macro-, micro- and nano-scaled defects and recombination of graphene nanosheets, the prepared GFs demonstrated amazing tensile strength of 778.49 MPa, Young's modulus of 92.61 GPa and an outstanding electrical conductivity of 3.2 × 104 S m−1, outperforming most of the chemically reduced GFs. This two-step green reduction strategy provides a new insight for constructing integrated high-performance GFs for sustainable application in many fields.