The Royal Society of Chemistry最新文献

Atomic force microscopy (AFM) provides a three-dimensional topographic representation of a sample surface, at nanometre resolution. Computational simulations can aid the interpretation of such representations, but have mostly been limited to cases where both the AFM probe and the sample are hard and not compressible. In many applications, however, the sample is soft and therefore deformed due to the force exerted by the AFM tip. Here we use finite element modelling (FEM) to study how the measured AFM topography relates to the surface structures of soft and compressible materials. Consistent with previous analytical studies, the measured elastic modulus in AFM is generally found to deviate from the elastic modulus of the sample material. By the analysis of simple surface geometries, the FEM modelling shows how measured mechanical and topographic features in AFM images depend on a combination of tip-sample geometry and indentation of the tip into the sample. Importantly for the interpretation of AFM data, nanoparticles may appear larger or smaller by a factor of two depending on tip size and indentation force; and a higher spatial resolution in AFM images does not necessarily coincide with a more accurate representation of the sample surface. These observations on simple surface geometries also extend to molecular-resolution AFM, as illustrated by comparing FEM results with experimental data acquired on DNA. Taken together, the FEM results provide a framework that aids the interpretation of surface topography and local mechanics as measured by AFM.

The poor disposal and lack of utilization of corn cob (CC) and corn silk (CS) generate environmental problems. This research aimed to develop CC and CS-based ingredients (1 : 1, 1 : 2, and 2 : 1 mixtures) and evaluate the in vitro gastrointestinal bioaccessibility of selected polyphenols and their anti-inflammatory effect. (+)-Catechin, gallic acid, and p-coumaric acid were detected (HPLC-DAD) at all digestion stages and are the major contributors to the observed antioxidant and anti-inflammatory effects in vitro. Compounds from the digestible fractions of the ingredients contributed to up to 60% of membrane stability in vitro in human red blood cells, compared to Diclofenac® (82%). (+)-Catechin was the compound exhibiting the highest anti-inflammatory effect in silico against anti- and pro-inflammatory PGE2, PPARγ, and COX-2 proteins at two model pH levels of membrane stability (5.7 and 7.0). Results suggested that polyphenols from agricultural residues (CC and CS) manufactured as ingredients are bioaccessible and exhibit potential biological effects, and could be used as potential feasible food ingredients.

Nitrogen doping effectively improves the adsorption properties of activated carbons towards volatile organic compounds (VOCs); however, the role of nitrogen elements with various chemical valence states need further evaluation. In this work, waste polyester fabrics were used as a low-cost source to prepare activated carbon, and melamine, pyridine, dimethylamine, and pyrrole were selected as nitrogen sources to compare their nitrogen-doping ability. The adsorption of low-concentration benzene and ethyl acetate on the resultant carbons and the effects of nitrogen, including its valence states and contents, were investigated. Characterizations showed that the nitrogen contents of carbons after doping with melamine (C-M), pyridine (C-P), dimethylamine (C-D), and pyrrole (C-Y) increased, while their corresponding specific surface areas were about 32.6%, 72.2%, 142% and 14.3%, respectively, of the original carbon value of 188.7 cm² g⁻¹. Dynamic breakthrough experiments verified the increase in adsorbed amounts of both non-polar benzene and polar ethyl acetate molecules, with a more significant enhancing effect on benzene. The specific surface area and pore volume mainly contribute to the adsorbed amounts. Regarding the influence of nitrogen-containing functional groups, pyridinic nitrogen was more conducive to benzene adsorption under dry conditions because of the stronger π–π interaction and N–H hydrogen bond; however, its water resistance was inferior to that of pyrrolic nitrogen. Saturated C-P can be effectively regenerated and the adsorbed capacity of benzene remained about 75% after five adsorption cycles. The increased adsorbed amount and super regeneration property identify pyridine as a nitrogen source with priority consideration in the nitrogen modification of activated carbons for VOC adsorption.

Bicyclo[6.1.0]nonyne carboxylic acid (BCN-COOH) is a valuable intermediate for the development of bioorthogonal click reagents. A convenient three-step synthesis of pure diastereomer anti-BCN-COOH is reported here, with an overall yield of 32% starting from 1,5-cyclooctadiene. To the best of our knowledge, this is the shortest route to anti-BCN-COOH known to date. The new method compares favourably with the optimised four-step synthesis based on previously reported data.

C-P bond formation reactions have garnered significant attention due to the widespread presence of organophosphorus compounds in pharmaceuticals, phosphine-containing ligands, pesticides, and materials science. Consequently, various efficient methodologies have been established in recent decades for constructing C-P bonds. This review article traces the historical evolution of C-P bond research and explores the prospects of C-P bond formation. It contrasts biotechnological approaches with chemical synthesis, emphasizing the critical importance of precision and innovation in developing novel C-P structures. A forward-looking perspective is provided on the role of computational tools and machine learning in optimizing C-P bond synthesis and discovering new compounds. The article explores prospective avenues for reactions that form C-P bonds and advocates for enhanced interdisciplinary collaboration to propel scientific and technological advancements.

Their unique characteristics make plastic films frequently utilised for packaging products. However, this petroleum-derived material has a long history of being linked to environmental contamination and hazardous degradation. Petroleum plastic can be substituted with edible packaging. The objective of this study was to combine sodium alginate with chitin, both in their nanosized form to formulate active packaging films containing different ratios of Zn/Al-layered double hydroxides (LDHs). Subsequently, active packaging films were formulated via a green method with different percentages (0%, 1%, 3%, and 5% w/w) of LDHs. The LDH particles were shaped as rectangular rods with a length of about 60 nm and width of around 20 nm. The films were evaluated for their physicochemical, topological, thermal, mechanical, water vapour, oxygen permeability and antimicrobial properties. Results indicated that active packaging with LDHs (3%) enhanced mechanical properties (tensile strength) by two-fold. Moreover, the addition of LDHs led to decreased permeability properties. Additionally, the antimicrobial study showed that the films with LDHs possessed a broad spectrum of antibacterial and antifungal activities, and the time required for bacterial killing was recorded to be less than 16 hours for films containing 5% LDHs. Thus, the formulated films show potential for use as active packaging.

Natural resource based polymers, especially those derived from proteins, have attracted significant attention for their potential utilization in advanced wound care applications. Protein based wound care materials provide superior biocompatibility, biodegradability, and other functionalities compared to conventional dressings. The effectiveness of various fabrication techniques, such as electrospinning, phase separation, self-assembly, and ball milling, is examined in the context of developing protein-based materials for wound healing. These methods produce a wide range of forms, including hydrogels, scaffolds, sponges, films, and bioinspired nanomaterials, each designed for specific types of wounds and different stages of healing. This review presents a comprehensive analysis of recent research that investigates the transformation of proteins into materials for wound healing applications. Our focus is on essential proteins, such as keratin, collagen, gelatin, silk, zein, and albumin, and we emphasize their distinct traits and roles in wound care management. Protein-based wound care materials show promising potential in biomedical engineering, offering improved healing capabilities and reduced risks of infection. It is crucial to explore the potential use of these materials in clinical settings while also addressing the challenges that may arise from their commercialization in the future.

The imperative advance towards achieving "carbon neutrality" necessitates the development of porous structures possessing dual acoustic and mechanical properties in order to mitigate energy consumption. Nevertheless, enhancing various functionalities often leads to an increase in the structural weight, which limits the feasibility of using such structures in weight-sensitive applications. In accordance with the outlined specifications, a novel structural design incorporating carbon fiber reinforced polymer (CFRP) composites alongside mechanical and acoustic metamaterials has been introduced for the first time. This innovative construction exhibits a lightweight composition with excellent mechanical and acoustic characteristics. Experimental findings demonstrate that with meticulous planning and fabrication, CFRP composite structures can achieve a balance of lightweight construction, high strength, exceptional energy absorption, and remarkable resilience. By introducing membrane and reasonable cavity design, the structure can produce low broadband noise reduction performance by a local resonance effect and impedance matching mechanism of metamaterials. The structural sound insulation capability breaks traditional mass law, resulting in an exceptionally broadband sound insulation peak (bandwidth of nearly 1000 Hz). Furthermore, the sound absorption characteristic of the structure surpasses that of the melamine sponge at frequencies below 300 Hz, demonstrating superior low-frequency sound absorption properties. The proposed structure provides new approaches for the design of multifunctional lightweight superstructures.

Black rice bran, a waste product from the commercial milling of black rice that removes the bran and germ leaving the starchy endosperm, contains bioactive anthocyanin, phenolic, and phytosteroid compounds that may have health benefits. This study determined the effect of a polysaccharide-rich bioprocessed (fermented) black rice bran and a green tea extract individually and in combination on weight loss in orally fed mice on a high-fat diet and on concurrent changes in blood glucose and insulin as well as in cholesterol, triglyceride, and high-density and low-density lipoproteins (HDL and LDL). At the end of the eight-week feeding study, the combination diet resulted in a 67% lower weight gain than mice on a high-fat diet alone, a greater effect than that of bioprocessed black rice bran or green tea extract individually. The weight loss caused by the combination diet seems to be the result of decreased dietary efficiency. The observed trends in the glucose and insulin data suggest that the combined diet also has anti-diabetic properties, and the corresponding trends in the levels of the serum lipoproteins suggest that the combined diet might also protect against heart disease. Effects on the content, structure, and function of white adipose and liver tissues and on obesity-related biomarkers support the trends in the weight loss data. Based on the observed beneficial effects in 3T3-L1 pre-adipocyte cells and mice, we suggest the need to investigate if the new multifunctional combination food product can also protect against obesity and chronic diseases in humans. Mechanistic aspects that govern the anti-obesity effects and suggestions for future research are discussed.

The photocatalytic reduction of CO₂ into valuable chemicals and fuels is considered a promising solution to address the energy crisis and environmental challenges. In this work, we introduce a Co-ZIL-L mediated in situ etching and integration process to prepare NiCo–OH with an ultrathin nanosheet-assembled 2D leaf-like superstructure (NiCo–OH UNLS). The resulting catalyst demonstrates excellent photocatalytic performance for CO₂ reduction, achieving a CO evolution rate as high as 309.5 mmol g⁻¹ h⁻¹ with a selectivity of 91.0%. Systematic studies reveal that the ultrathin nanosheet structure and 2D leaf-like architecture not only enhance the transfer efficiency of photoexcited electrons but also improve the accessibility of active reaction sites. Additionally, the Ni–Co dual sites in NiCo–OH UNLS accelerate CO₂ conversion kinetics by stabilizing the *COOH intermediate, significantly contributing to its high activity. This work offers valuable insights for designing advanced photocatalysts for CO₂ conversion.