低共熔溶剂的应用研究现状

低共熔溶剂是两种或多种固体或液体物质通过氢键相互作用形成的液体溶剂,其熔点明显低于单一组分的熔点。与传统离子液体相比,低共熔溶剂成本更低,制备更容易,可生物降解,具有100%原子利用率和生物相容性及无毒无害等绿色特性,这些优点使其在许多研究领域被广泛研究。本文介绍了低共熔溶剂的最新分类,综述了低共熔溶剂在电化学、气体吸收、有机合成、功能材料合成、萃取分离、药物增溶及生物质预处理中的应用,并对低共熔溶剂的未来发展进行了展望。     

基于MXenes的功能纤维的制备及其在智能可穿戴领域的应用

在电子信息和物联网技术的推动下,人类对可穿戴电子器件和智能织物的需求愈发突出,功能纤维作为智能可穿戴设备的重要载体,近年来获得快速发展。功能纤维的性能很大程度上取决于纤维的基础构筑单元。过渡金属碳/氮化物(MXenes)作为一种新兴的二维材料,凭借其高电导率、优异的可加工性能、可调节的表面特性以及出色的机械强度等优点,受到了极大的关注,也逐渐成为构筑功能纤维的重要单元。本文将主要综述MXenes的湿化学、熔融盐、无氟试剂刻蚀等方法和力学、电学、光学和化学稳定性等性能,阐述基于该材料制备的功能纤维在传感、储能以及其他智能领域的应用,最后讨论了基于MXenes材料的功能纤维的未来应用前景和技术挑战。     

A Highly Sensitive and Selective Label-free Electrochemical Biosensor with a Wide Range of Applications for Bisphenol A Detection

A label-free DNA-based electrochemical biosensor owning high sensitivity and selectivity has been established for detecting bisphenol A in a wide range of applications. Coupling the high electrochemical performance of graphene oxide-thionine-Au nanomaterial with the specific binding capacity of the aptamers to BPA, the monitoring of trace amount of BPA was realized, the detection limit was 3.3 pg ⋅ mL⁻¹ with strong anti-interference. Besides, using molecular docking, it was found that BPA binds to the bases DC-49, DC-51, DG-52, DG-53 and DA-63 on the aptamer via hydrogen bonding and π-π stacking interactions. Finally, the biosensor had been successfully applied in different real samples.     

Green synthesis and characterization of copper and nickel hybrid nanomaterials: Investigation of their biological and photocatalytic potential for the removal of organic crystal violet dye

Nanotechnology deals with the materials at nanoscale to synthesize nanoparticles. The current study introduced a new green approach for the synthesis of Copper and Nickel hybrid nanoparticles by using Zingiber officinale rhizome extract as a capping and reducing agent. The nanoparticles were physico-chemically characterized by UV–visible spectroscopy, Fourier transform infrared spectroscopy, X-ray powder diffraction, Energy-dispersive X-ray spectroscopy, and Scanning electron microscopy. It was revealed by scanning electron micrograph that the Cu-Ni hybrid nanoparticles have spherical geometries with average grain size of 25.12 ± 1.2 nm. Furthermore, biocatalytic and photocatalytic applications of the biosynthesized nanoparticles were assessed. The results of antibacterial assay revealed that Cu-Ni hybrid nanoparticles had an inhibition zones of 28 ± 1.0, 25 ± 0.8, and 25 ± 1.5 mm against P. aeruginosa, E. coli and Proteus vulgaris. Commercially available antibiotics were purchased and coated with Cu-Ni hybrid nanoparticles, it was found that their antimicrobial efficacy was increased twice. To evaluate the antioxidant potential, nanoparticles having a concentration of 200 µg/mL were applied against 2,2-diphenyl-1-picrylhydrazyl free radicals and NPs showed 42.1 ± 0.71 % inhibition. Cu-Ni nanoparticles have shown a dose-dependent cytotoxicity against amastigote and promastigote in anti-leishmanial assay. The synthesized nanoparticles were found biocompatible and safe in nature to be used in vivo, as they showed no significant hemolysis of human red blood cells at their highest concentration. In antidiabetic assay, NPs inhibited alpha-amylase enzyme up to 38.07 ± 0.65 %. An organic crystal violet dye was successfully degraded by the synthesized nanoparticles in photocatalytic assay. Hence, it is concluded that Cu-Ni hybrid nanoparticles can be used both in vitro and in vivo for drug delivery in biomedical research. These nanoparticles can also be used in the remediation of organic dyes as a catalyst.     

Regulating the Oil-Water Interface to Construct Double Emulsions: Current Understanding and Their Biomedical Applications

Double emulsions have been extensively used in scientific researches and industrial applications due to their attractive unique feature of multiple phases. However, constructing droplets with such a complex structure is not a simple task for all time. The simultaneous existence of two contradictory interfaces makes it hard to prepare stable double emulsions in principle and in practice. Over the past century, tremendous efforts have been devoted by myriads of scientists to make progresses in both theory and preparation of double emulsions. In this review, the current understanding of double emulsions is systematically revealed. In addition to emphasizing the corresponding pioneer and landmark works as many as possible, the state-of-the-art achievements will also be discussed. By regulating the oil-water interface with smartly designed interface-active agents in combination with varying the phase volume fractions, the basic theory framework based on the phase inversion from simple emulsions to double emulsions is also summarized. Technical preparation strategies of emulsification are introduced to show the building process of the two contradictory interfaces in one system. Furthermore, some specific biomedical applications of double emulsions are also discussed, which is expected to stimulate further innovation and utilization of double emulsions.     

Graded regulation technology for enhanced oil recovery and water shutoff in pore-cavity-fracture carbonate reservoirs

Although a single type of chemical agent (eg, gels, microspheres, surfactants, etc.) has achieved some effects in enhanced oil recovery of carbonate reservoirs, for pore-cavity-fracture carbonate reservoirs, the use of a single type of chemical agent does not perform well. The main objective of this study is to study the effect of different types of chemical agents in enhanced oil recovery of complex carbonate reservoirs. In order to determine the screening principle of chemical agents, the types of water channeling in the North Troyes reservoir were analyzed. For complex fractures, step by step plugging, multi-agent and multi-slug comprehensive intervention is carried out to ensure the plugging of high-permeability channels and inhibit the seepage of large channels. It can plug channeling fracture channel, adjust secondary dominant channel and reduce matrix flow resistance, so as to expand macroscopic swept volume and improve microscopic water flooding efficiency. The results show that it is difficult to comprehensively control water channeling in pore-cave-fracture carbonate reservoir, and the reservoir heterogeneity in the test area can be improved by mixing different types of control and flooding agents and carrying out deep profile control. The plugging rate of gel is 97.18 %, and the oil–water selection ratio is 0.45 in fractured core; the expansion rate of nano - microspheres is more than 3 times; the wetting modifier can improve the imbibition oil displacement efficiency by 14.76%, and the test result shown that nano - microspheres and wetting modifier have good synergistic oil displacement effect. The field application result shown that daily oil production of oil well in the test area increased by 5.0 m³/d and the daily water rate decreased by 19.0% compared with that before the control flooding. The findings of this study can help for better understanding of enhanced oil recovery in pore-cave-fracture carbonate reservoir.     

Preparation and fabrication of porous-Fe2O3/carbon black nanocomposite: a portable electrochemical sensor for psychotropic drug detection in environmental samples

Herein, we reported the fabrication of porous iron oxide/carbon black (P–Fe₂O₃/CB) composite through a two-step engineering method. At first, Prussian blue microcubes were used as a precursor and further calcined to form P–Fe₂O₃ microcubes. The intercalation of CB nanoparticles with P–Fe₂O₃ nanocubes was processed through the ultrasonication method. The obtained P–Fe₂O₃/CB were successfully scrutinized through various physiochemical characterization methods. The proposed P–Fe₂O₃/CB-modified glassy carbon electrode sensor was successfully implemented in the electrochemical sensing of chlorpromazine hydrochloride due to its very low charge transfer resistance (R_ct) compared to the other electrode modifiers. The sensitive detection of CPMH through differential pulse voltammetry exemplifies an excellent electroanalytical performance such as a wide linear range of 0.5–1472 μM, a lower detection limit (0.001 μM), and an appraisable sensitivity of 1.99 μA/μM cm^?2 due to its availability of a high number of active sites and its large surface area, respectively. It also expresses excellent selectivity, repeatability, reproducibility, and stability results. Moreover, the practical feasibility of the as-fabricated P–Fe₂O₃/CB/glassy carbon electrode sensor shows exquisite recovery (98.1–100.8%) results with an appraisable current response in various biological, pharmaceutical, and environmental samples.     

Preparation,Bioactivities and Applications in Food Industry of Chitosan-Based Maillard Products: A Review

Chitosan, a biopolymer possessing numerous interesting bioactivities and excellent technological properties, has received great attention from scientists in different fields including the food industry, pharmacy, medicine, and environmental fields. A series of recent studies have reported exciting results about improvement of the properties of chitosan using the Maillard reaction. However, there is a lack of a systemic review about the preparation, bioactivities and applications in food industry of chitosan-based Maillard reaction products (CMRPs). The presence of free amino groups in chitosan allows it to acquire some stronger or new functional properties via the Maillard reaction. The present review aims to focus on the current research status of synthesis, optimization and structural identification of CMRPs. The applications of CMRPs in the food industry are also discussed according to their biological and technological properties such as antioxidant, antimicrobial activities and inducing conformational changes of allergens in food. Some promising directions for future research are proposed in this review, aiming to provide theoretical guidance for the further development of chitosan and its derivatives.     

Graphdiyne:from Preparation to Biomedical Applications

Graphdiyne(GDY)is a kind of two-dimensional carbon nanomaterial with specific configurations of sp and sp2 carbon atoms.The key progress in the preparation and application of GDY is bringing carbon materials to a brand-new level.Here,the various properties and structures of GDY are introduced,including the existing strategies for the preparation and modification of GDY.In particular,GDY has gradually emerged in the field of life sciences with its unique properties and performance,therefore,the development of biomedical applications of GDY is further summarized.Finally,the challenges of GDY toward future biomedical applications are discussed.     

Progress in Molecular Nanoarchitectonics and Materials Nanoarchitectonics

Although various synthetic methodologies including organic synthesis, polymer chemistry, and materials science are the main contributors to the production of functional materials, the importance of regulation of nanoscale structures for better performance has become clear with recent science and technology developments. Therefore, a new research paradigm to produce functional material systems from nanoscale units has to be created as an advancement of nanoscale science. This task is assigned to an emerging concept, nanoarchitectonics, which aims to produce functional materials and functional structures from nanoscale unit components. This can be done through combining nanotechnology with the other research fields such as organic chemistry, supramolecular chemistry, materials science, and bio-related science. In this review article, the basic-level of nanoarchitectonics is first presented with atom/molecular-level structure formations and conversions from molecular units to functional materials. Then, two typical application-oriented nanoarchitectonics efforts in energy-oriented applications and bio-related applications are discussed. Finally, future directions of the molecular and materials nanoarchitectonics concepts for advancement of functional nanomaterials are briefly discussed.