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In the classical natural product extraction and separation process, it is tedious and requires large amounts of reagents and time. In this study, an efficient coaxial liquid centrifugal oil‐water‐oil triple‐liquid‐phase system with a simple structure and convenient operation was successfully constructed and used to extract flavonoids from Platycladi Cacumen. The results showed that the coaxial liquid centrifugal platform constructed in this study had good stability and 6 ml was the minimum volume of the middle phase for 1000 rpm to stabilize the system. Besides, it was easy to repeat the operation: the relative standard deviations of the extraction yields of flavonoids and sugar in six parallel operations were all less than 10%. Moreover, it was only one‐tenth of the time required for this method as traditional liquid‐liquid extraction while reducing the use of volatile organic reagents. Finally, the new method was more selective than the traditional method for the extraction of flavonoids. Therefore, this study provides a possibility for the coaxial liquid centrifugal platform to be used in multi‐liquid phase systems to achieve the simultaneous extraction of different parts of natural products by different liquid phases. It is expected to provide a reliable reference for further expansion of small‐scale experimental operations to industrial production. [ABSTRACT FROM AUTHOR]

To overcome the low concentration and matrix complexity of N1-methylnicotinamide (MeNam) in biological samples, this work developed a method for the detection of MeNam in urine samples using a Fe3O4@hydroxypropylmethylcellulose@2,3-dimercaptosuccinic acid (Fe3O4@HPMC@DMSA) magnetic fluid as a pre-treatment material in combination with high performance liquid chromatography. The novel adsorbent material exhibited ultra-fast adsorption kinetics and a large adsorption capacity because Fe3O4@HPMC@DMSA NPs acted as a homogeneous magnetic fluid with more varieties and quantities of interaction sites (hydrogen-bonding interaction and electrostatic interaction). The limit of determination for MeNam was 0.05 μg mL−1 with Fe3O4@HPMC@DMSA NPs. Recoveries of spiked urine samples ranged between 95.49% and 106.4%, indicating that the developed method was promising for the accurate quantification of trace amounts of MeNam in urine samples. It provides research value for the rapid assessment of the nutritional effects of NMN dietary supplements and offers a sensitive assay for metabolism studies of related functional foods. [ABSTRACT FROM AUTHOR]

Personalised recommendation is a difficult problem that has received a lot of attention to academia and industry. Because of the sparse user–item interaction, cold-start recommendation has been a particularly difficult problem. Some efforts have been made to solve the cold-start problem by using model-agnostic meta-learning on the level of the model and heterogeneous information networks on the level of data. Moreover, using the memory-augmented meta-optimisation method effectively prevents the meta-learning model from entering the local optimum. As a result, this paper proposed memory-augmented meta-learning on meta-path, a new meta-learning method that addresses the cold-start recommendation on the meta-path furthered. The meta-path builds at the data level to enrich the relevant semantic information of the data. To achieve fast adaptation, semantic-specific memory is utilised to conduct the model with semantic parameter initialisation, and the method is optimised by a meta-optimisation method. We put this method to the test using two widely used recommended data set and three cold-start scenarios. The experimental results demonstrate the efficiency of our proposed method. [ABSTRACT FROM AUTHOR]

The attention to chiral drugs has been raised to an unprecedented level as drug discovery and development strategies grow rapidly. However, separation of enantiomers is still a huge task, which leads to an increasing significance to equip a wider range of expertise in chiral separation science to meet the current and future challenges. In the last few decades, remarkable progress of chiral resolution has been achieved. This review summarizes and classifies chiral resolution methods in analytical scale and preparative scale systematically and comprehensively, including crystallization‐based method, inclusion complexation, chromatographic separation, capillary electrophoresis, kinetic resolution, liquid–liquid extraction, membrane‐based separation, and especially one bold new progress based on chiral‐induced spin selectivity theory. The advances and recent applications will be presented in detail, in which the contents may bring more thinking to wide‐ranging readers in various professional fields, from analytical chemistry, pharmaceutical chemistry, natural medicinal chemistry, to manufacturing of drug production. [ABSTRACT FROM AUTHOR]

Magnetic carbon nanotubes (MCNTs), consisting of carbon nanotubes (CNTs) and magnetic nanoparticles (MNPs), have enormous exploration and application potentials due to their superior physical and chemical properties, such as unique magnetism and high enrichment performance. This review concentrates on the rapid advances in the synthesis and application of magnetic carbon nanotubes. Great progress has been made in the preparation of MCNTs by developing methods including chemical vapor deposition, pyrolysis procedure, sol–gel process, template-based synthesis, filling process and hydrothermal/solvothermal method. Various applications of MCNTs as a mediator of the adsorbent in magnetic solid-phase extraction, sensors, antibacterial agents, and imaging system contrast agents, and in drug delivery and catalysis are discussed. In order to overcome the drawbacks of MCNTs, such as sidewall damage, lack of convincing quantitative characterization methods, toxicity and environmental impact, and deficiency of extraction performance, researchers proposed some solutions in recent years. We systematically review the latest advances in MCNTs and discuss the direction of future development. [ABSTRACT FROM AUTHOR]

A series of new N-acylhydrazone derivatives were synthesized in good yields through the reactions of dehydroabietic acid hydrazide with a variety of substituted arylaldehydes. The structures of the synthesized compounds were confirmed by IR, 1H- and 13C-NMR, ESI-MS, elemental analysis and single crystal X-ray diffraction. From the crystal structure of compound 4l, the C=N double bonds of these N-acylhydrazones showed (E)-configuration, while the NMR data of compounds 4a-q indicated the existence of two rotamers for each compound in solution. The target compounds were evaluated for their antibacterial activities against four microbial strains. The result suggested that several compounds exhibited pronounced antibacterial activities. Particularly, compound 4p exhibited good antibacterial activity against Staphylococcus aureus and Bacillus subtilis comparable to positive control. The possible antibacterial metabolism and the strategy for further optimization of this compound were also discussed.