Chemical Reagents

Research Progress in Intelligent Analytical Methods for Near-Infrared Spectroscopy

Near-infrared spectroscopy( NIRS) has been widely applied in many fields owing to its advantages of rapid analysis,nondestructive measurement,simple sample pretreatment,and suitability for online detection. With the increasing demand for complex sample analysis,NIRS research was expanding from traditional workflow optimization,including preprocessing,variable selection,and calibration modeling,toward mechanistic interpretation,spatial-spectral fusion,and emerging intelligent analytical methods.This paper reviewed recent advances in water spectral probes,hyperspectral imaging,large language models and spectral analysis agents,quantum computing,and quantum-inspired methods. Special attention was given to the role of water-structure responses in the mechanistic interpretation of near-infrared information and their value in revealing intermolecular interactions and information sources in complex systems. The advantages of hyperspectral imaging in the joint spatial-spectral characterization of heterogeneous samples were discussed,highlighting its importance in improving sample identification,localization,and quantitative analysis.In addition,the potential of spectral analysis agents in knowledge organization,workflow coordination,and modeling support was summarized,and the role of large language models in promoting spectral analysis from single-step modeling toward knowledge-enhanced and multi-tool collaborative analysis was examined.The potential value of quantum computing and quantuminspired methods in spectral simulation,data augmentation,high-dimensional feature mapping,variable selection,and spatialspectral data processing was also discussed. Finally,future development trends in mechanistic interpretation,spatial-spectral fusion,and emerging intelligent analytical methods for NIRS were discussed to provide a useful reference for related research.

Recent Advances in Rapid Antimicrobial Susceptibility Testing Based on Bacterial Metabolic Activity

The increasing severity of antibiotic resistance has raised higher demands on the timeliness and accuracy of clinical antimicrobial susceptibility testing( AST).Although traditional culture-based AST methods remained the gold standard,their long turnaround time limits their ability to meet the clinical need for early and precise antimicrobial therapy.Therefore,developing rapid phenotypic AST techniques that could directly detect bacterial responses to antibiotics within a short timeframe is of great significance.This review focused on rapid AST strategies based on monitoring changes in bacterial metabolic activity. From the perspective of metabolic response as an early indicator of antibiotic action,we systematically reviewed the technological advances across different signal transduction pathways. By analyzing antibiotic-induced changes in bacterial oxygen consumption,cell wall synthesis activity,energy metabolism,extracellular electron transfer,and metabolite release,this article further summarized the major detection modalities,including luminescence/fluorescence,Raman spectroscopy,electrochemistry,and colorimetry,and compares their characteristics in terms of detection speed,sensitivity,sample compatibility,and clinical translational potential.Overall,metabolic activity-based AST methods offered faster turnaround times compared with traditional growth-dependent approaches,enabled early detection of bacterial drug responses,and hold significant promise for improving testing efficiency and guiding clinical antimicrobial therapy.

Atmospheric Pressure Low-Temperature Microplasma Synthesis Methodology: Principle,Device and Applications

The development of atmospheric-pressure low-temperature microplasma provides a unique and promising route for the synthesis of multifunctional nanomaterials. Depending on the type of discharge and the distribution of the electric field,the atmospheric-pressure low-temperature microplasma could generate stable discharges in the gas phase,liquid phase,and at the gasliquid interfaces,forming various low-temperature microplasma states such as glow discharge,dielectric barrier discharge,and corona discharge.The synthesis mechanism relied on the abundant reactive species-such as photons,electrons,ions,free radicals,and excited molecules and atoms-present within the interior and boundary layer of the microplasma.High-energy electrons excited or dissociated the background gas and precursor molecules through inelastic collisions,generating reactive species.These reactive species acted as initiators or reducing agents,inducing cleavage,reduction,or polymerization of precursors,thereby promoting nucleation and growth of the target materials. Since the microplasma was in a non-thermodynamic equilibrium state,where the electron temperature was much higher than the macroscopic gas temperature,while the gas temperature could remain near room temperature,the combination of high-energy activation and a mild thermal environment provided unique reaction conditions for material synthesis. At the same time,the confinement effected within the microscale discharge space significantly shortens the diffusion paths of reactants and active species,markedly reduced mass transfer resistance,and thus facilitates highly efficient reactions.Compared with traditional wet-chemical synthesis or conventional electrochemical deposition,this method offered several distinct advantages: the synthesis typically took only tens of minutes,considerably shorter than the several hours or even days required by traditional methods; no surfactants or strong reducing agents were needed,as the reaction was driven solely by the reactive components inherent to the plasma,thereby avoiding byproduct impurity; and the apparatus was compact,energy-efficient,and operable under mild conditions at ambient temperature and pressure. Furthermore,by adjusting the discharge parameters,the types and concentrations of reactive species could be effectively controlled,thereby enabling regulation of the synthesis process.This article reviewed the fundamental principles of this synthesis method,the various reactor configurations( such as discharge mode into hollow-electrode reactors,microplasma jet reactors,dielectric barrier discharge reactors,and array reactors),as well as the synthesis of diverse nanomaterials-including metal oxides and composites,organic framework compounds,noble metal nanoparticles,and carbon-based nanomaterials. Recent applications in analytical testing were also summarized,demonstrating the promising application of this technique in fields such as precision nanomaterial synthesis,green chemistry,and analytical sensing.

Advances in Point-of-Care Testing of Exosomes for Tumor Liquid Biopsy

Tumor-derived exosomes carry nucleic acids,proteins,lipids,and other molecular information inherited from their parental cells,allowing them to dynamically reflected tumor initiation,progression,molecular subtype,and therapeutic response.They were therefore promising biomarkers for noninvasive liquid biopsy. Nevertheless,point-of-care analysis of tumor-derived exosomes remained technically challenging because these vesicles were present at low abundance in body fluids,coexist with abundant proteins,lipoproteins,and cell debris,and exhibit substantial molecular heterogeneity. These features placed stringent requirements on enrichment efficiency,recognition specificity,signal amplification,analytical stability,and operational simplicity.This review summarized recent advances in point-of-care testing( POCT) technologies for tumor exosomes. First,the major analytical bottlenecks imposed by microliter-scale samples,complex biological matrices,and non-standard operating environments were discussed. The available approaches were then organized from two complementary perspectives: signal-transduction mechanisms and device-integration platforms. Colorimetric,fluorescence,surface-enhanced Raman scattering,and electrochemical sensing were reviewed with emphasis on their recognition and amplification principles,whereas microfluidic chips and paper-based analytical devices were discussed as integrated platforms for sample pretreatment,exosome enrichment,reaction control,and portable readout.Their representative performance was further compared in terms of limit of detection,linear range,total assay time,cost,equipment dependence,operational complexity,and intended application. Colorimetric methods were generally suitable for rapid and low-cost screening,whereas fluorescence,electrochemical,and Raman-based approaches provided greater analytical sensitivity and multiplexing capability but often required additional labels or dedicated readers. Microfluidic platforms offered automated fluid handling and high integration,while paper-based devices provide low-cost operation and broad accessibility,particularly in resource-limited settings. Particular attention was paid to multi-target detection,dual-recognition logic gates,spatially encoded assays,and orthogonal protein-nucleic acid validation,which could reduce false-positive results and improve the discrimination of tumor-derived exosomes from vesicles released by normal cells. Clinical validation studies were subsequently reviewed by cancer type,including breast,lung,colorectal,and gastric cancers,highlighting differences in biomarker selection,sample type,sensing strategy,cohort size,and diagnostic performance. Finally,key barriers to clinical translation were discussed,including the lack of standardized isolation and quantification procedures,batch-to-batch variation and mass-production challenges for sensing devices,insufficient prospective multicenter validation,and limited evaluation under real-world clinical conditions.Future directions included multimodal signal fusion,artificial-intelligence-assisted interpretation,wearable and home-based testing,and single-exosome omics.Collectively,these developments might facilitate the transition of exosome POCT from laboratory proof-of-concept studies toward practical tools for cancer screening,molecular stratification,treatment-response assessment,and longitudinal monitoring.

Progress and Challenge on Environmental Radioanalysis of Plutonium Isotopes

Since the advent of nuclear energy in the twentieth century,atmospheric nuclear weapons testing,nuclear accidents,and spent nuclear fuel reprocessing have released substantial quantities of radionuclides into the environment,including highly toxic plutonium isotopes. The concentrations and isotopic compositions of Pu in environmental samples were important indicators for assessing anthropogenic radioactive contamination,identifying sources of nuclear contamination,and understanding its environmental behavior and transport. The analytical methods for plutonium isotopes in the environment was therefore of great significance for nuclear environmental safety assessment. Previous review articles on plutonium analysis generally focused on specific sample types,individual separation materials,or particular measurement techniques,whereas the individual steps of Pu isotope analysis and their interconnections had not been systematically reviewed,hindering the rational selection of proper analytical methods and the intercomparison of measurement results. This review systematically summarized the current status and recent advances in the pretreatment of samples,separation and purification of plutonium,and measurement of Pu isotopes in environmental samples,including soils,sediments,and waters. Different analytical techniques were compared in terms of sampleprocessing capacity,separation selectivity,interference removal,detection limits,and measurement precision. Some applications of Pu isotopes analytical methods in nuclear environmental safety assessment and environmental process tracing were briefly demonstrated,including source apportionment,sediment dating,water-mass movement tracing,and soil erosion assessment.Finally,the major challenges and future development trends of analytical methods for Pu isotopes in environmental samples were discussed,aiming to provide technical support for radioactive contamination monitoring and regulation,nuclear environmental safety assessment,and environmental process studies.

Raman Spectroscopy for the Qualitative Study of Cathinone-Type New Psychoactive Substances

In recent years， new psychoactive substances (NPS) have spread rapidly worldwide and evolved into severely hazardous “third-generation drugs”， following traditional first- and second-generation illicit drugs that have long threatened public security. Cathinone derivatives are among the most prevalent classes of new psychoactive substances. In terms of abuse frequency， affected population， and social harm， they rank second only to synthetic cannabinoids， which are currently the most rampant NPS. Long-term or excessive abuse of cathinone-type substances induces intense excitation of the central nervous system， causing mental agitation， behavioral disorders， and physical dysfunction. Such substance misuse leads to family breakdowns， social conflicts， and even criminal acts， posing enormous hidden risks and immeasurable adverse effects on social governance and public safety. Raman spectroscopy outperforms conventional analytical methods owing to its simple operation， ultrafast detection， and superior stability. It enables the simultaneous qualitative analysis of multiple targets via a one-step procedure， making it highly applicable to rapid on-site drug identification. In this study， a rapid， highly sensitive， and reliable Raman spectroscopy method was established for the qualitative identification and screening of new cathinone-type psychoactive substances. A portable Raman spectrometer was adopted for detection， and the instrumental parameters were optimized to a laser wavelength of 785 nm， laser power of 300 mW， and spectral scanning range of 150～3000 cm⁻¹. Systematic detection and spectral analysis were conducted on 20 common cathinones under optimized conditions. Accurate classification and effective differentiation between cathinone derivatives and other psychoactive substances were achieved by summarizing and comparing the unique characteristic spectral peaks of cathinone compounds. Targeting the technical challenge of structural-similarity recognition， we investigated the ability of this method to distinguish cathinone isomers with highly analogous molecular structures. A standardized Raman spectral database for the 20 tested cathinones was established， and multiple parallel experiments were performed to validate the stability of the proposed method. The experimental results demonstrate that the established Raman spectroscopic method possesses high specificity and excellent stability. It enables efficient， rapid， and accurate identification of new cathinone-type psychoactive substances; provides a robust technical tool for grassroots law enforcement， on-site drug screening， and judicial identification; and offers solid technical support for maintaining social order and safeguarding public security and stability.

Determination of Aluminum in Injections by ICP-MS/MS with Matrix Matching Method Combined with Total Matrix Introduction

An inductively coupled plasma mass spectrometry (ICP-MS) method based on matrix matching combined with a total matrix introduction system was established for the determination of aluminum content in compound sodium acetate Ringer's injection. This method was developed primarily to mitigate severe matrix interference arising from the high salt and sugar content of pharmaceutical formulations while enabling direct sample introduction without complex pretreatment， thereby reducing the risk of external contamination and improving detection efficiency. In this system， a total matrix introduction device was employed to introduce a dilution gas for online gas dilution before the sample aerosol entered the plasma. This approach effectively reduced the matrix load on the plasma and stabilized the ionization conditions. The instrumental parameters were systematically optimized to achieve robust performance with a nebulizer gas flow rate of 0.79 L/min and a dilution gas flow rate of 0.20 L/min. To correct for non-spectral matrix effects caused by variations in sample viscosity and transport efficiency， ⁴⁵Sc was selected as the internal standard element. To further reduce residual matrix interference， 0.2% anhydrous glucose was used for matrix matching in both the calibration standards and sample solutions. Additionally， tandem quadrupole (ICP-MS/MS) technology combined with helium (He) collision mode was adopted to effectively eliminate polyatomic ion interference， particularly from chloride- and carbon-containing species. Methodological validation demonstrated a good linear relationship between the mass concentration of aluminum and response intensity within the range of 5 to 50 μg/L， with a correlation coefficient greater than 0.999. The average recoveries of spiked samples at three different spiking levels ranged from 97% to 104%， and the relative standard deviation for repeatability was 2.5%， indicating satisfactory accuracy and precision of the proposed method. Quantitative analysis of six batches of samples revealed relatively low aluminum content， suggesting a negligible safety risk for clinical applications. In summary， the established method， which integrates total matrix introduction with matrix matching， enables direct sample introduction for the determination of aluminum in high-salt and high-sugar matrix injections， effectively controlling both matrix and spectral interference. The method is simple， accurate， and reliable， making it suitable for routine determination of aluminum content in compound sodium acetate Ringer's injection and providing a valuable methodological reference for rapid batch analysis of other complex matrix injections in pharmaceutical quality control laboratories.

Study on Synthesis and Antitumor Activity of Celastrol Derivatives

Cancer has become a severe global public-health threat with continuously rising morbidity and mortality rates. Despite the remarkable advances in antitumor drug development， conventional clinical chemotherapeutic drugs still suffer from inherent limitations， including poor tumor selectivity， obvious toxic side effects， and frequent multidrug resistance， which severely restrict their clinical application and therapeutic efficacy. Celastrol， a naturally occurring pentacyclic triterpene derived from the medicinal plant named Tripterygium wilfordii Hook.f.， exhibits diverse pharmacological activities. Nevertheless， its poor water solubility， rapid in vivo metabolism， and narrow therapeutic window considerably hinder its clinical transformation; thus， reasonable structural modification was required to optimize its druggability. Epidermal growth factor receptor (EGFR) was a core therapeutic target for multiple malignancies， including liver cancer and non-small cell lung cancer， whose abnormal overexpression or mutation drives tumor proliferation and metastasis; thus， it was an ideal target for antitumor drug research. In this study， several novel celastrol derivatives were designed and synthesized， and the in vitro antitumor activities of celastrol and its derivatives were examined. Celastrol was used as the starting material to synthesize target compounds 3a～3h through the amidation reaction at the 28-carboxyl group and the esterification reaction at the 3-hydroxyl group of celastrol. The in vitro antitumor activities of the target compounds were determined using a CCK-8 assay against HepG2 human hepatocellular carcinoma cells and A549 human lung cancer cells. Additionally， molecular docking was performed to simulate the binding mode between the target compounds and EGFR. A series of novel celastrol derivatives were successfully synthesized and reported for the first time. The chemical structures of the synthesized compounds were characterized by performing high-resolution mass spectrometry (electrospray ionization)， proton nuclear magnetic resonance spectroscopy， and carbon-13 nuclear magnetic resonance spectroscopy. The results of in vitro antitumor activity assays showed that all compounds exhibited better inhibitory abilities than the positive control， cisplatin. Compounds (9β，13α，14β，20α)-3-benzoyloxy-9，13-dimethyl-29-(1-pyrrolidinyl)-24，25，26-trinoroleana-1(10)，3，5，7-tetraene-2，29-dione(3c) and (9β，13α，14β，20α)-3-benzoyloxy-9，13-dimethyl-29-(1-piperidinyl)-24，25，26-trinoroleana-1(10)，3，5，7-tetraene-2，29-dione(3f) exhibited prominent inhibitory activities against HepG2 cells (3c：IC₅₀ = 2.97 μmol/L， 3f：IC₅₀ = 3.18 μmol/L) and A549 cells (3c：IC₅₀ = 0.57 μmol/L， 3f：IC₅₀ = 0.61 μmol/L). Molecular-docking simulations revealed favorable binding interactions with EGFR protein formed by both 3c and 3f through hydrogen bonding， hydrophobic effects， and other noncovalent interactions. Among all the newly synthesized celastrol derivatives， the two derivatives with benzoyloxy substitution at the C-3 site exhibited the strongest antitumor activity. Such structural modification is preliminarily suggested to have played a vital role in improving the antitumor activity of celastrol， and further comprehensive research is warranted.

Preparation and Application of Molecularly Imprinted Biochar Using Dopamine as Functional Monomer Tetracycline (TC) residues in environmental waters have become a widespread environmental problem owing to their refractory degradation， biological toxicity， and potential ecological risks. Conventional biochar adsorbents exhibits low adsorption efficiency and poor specific selectivity for TC， limiting their practical application in water pollution treatment. To overcome these limitations， biochar was synergistically modified using phosphoric acid activation and mechanical ball milling (BPBC) as a molecular imprinting carrier. Dopamine， a green and efficient functional monomer with excellent biomimetic adhesion and abundant hydrophilic hydroxyl and amino functional groups， was selected as the functional monomer. TC was used as a template molecule. A novel molecularly imprinted biochar material， BPBC@DA-MIP， was successfully fabricated via mild aqueous-phase oxidative polymerization. The material features abundant specific adsorption sites and exhibits excellent environmental compatibility. The key preparation parameters of BPBC@DA-MIPs were systematically optimized， and their micromorphology， structural characteristics， and surface functional group properties were comprehensively characterized. Batch adsorption experiments demonstrated its selective adsorption performance for TC. The optimized BPBC@DA-MIPs possessed high specific surface area dense oxygen- and nitrogen-containing functional groups. Adsorption kinetic equilibrium was achieved within 120 min， indicating rapid adsorption kinetics of TC. A prominent maximum adsorption capacity (267.28 mg/g) and ideal imprinting factor (1.99) were obtained， confirming the successful construction of specific recognition sites with superior specific selectivity for TC. Moreover， the material exhibited strong anti-interference ability against complex environmental matrices and excellent recycling stability， retaining 75% of its original adsorption capacity after 10 adsorption–desorption cycles. Coupled with HPLC， a novel sensitive and selective analytical method for trace TC detection in environmental water was established using BPBC@DA-MIPs as solid-phase extraction adsorbents. The method achieved low limits of detection (1.78 ng/mL) and quantification (5.93 ng/mL)， with satisfactory spiked recovery rates ranging from 92.3% to 97.4% in actual water samples. The newly prepared BPBC@DA-MIPs offer efficient removal and high-precision detection of trace TC contaminants in aqueous environments. This feasible and innovative strategy overcomes conventional biochar’s low selectivity， enabling practical treatment and trace analysis of antibiotics in environmental water.

Synthesis of Peptide Zinc and Peptide Calcium Reagents Using Microwave Method and Their Application

Zinc and calcium are essential minerals for the human body， and their deficiencies are prevalent worldwide， particularly in developing countries. Currently， most commercially available zinc/calcium supplements are inorganic salts or simple organic acid salts， which tend to dissociate under gastric-acid conditions to form precipitates such as zinc chloride and calcium chloride. This not only significantly reduces the bioavailability of the metal ions but may also cause gastrointestinal irritation. In this study， natural proteins from soybean， casein， corn， and Antarctic krill were hydrolyzed using alkaline protease， trypsin， and pepsin under their respective optimal conditions (pH， temperature， time， enzyme-to-substrate ratio， and protein-to-water ratio) to obtain small bioactive peptides with molecular weights ranging from 250 to 450 Da. Microwave oscillation technology (optimal time: 3 min) was utilized to unfold the helical conformation of the peptide chains， thus exposing more coordination sites. Subsequently， the peptides were complexed with Zn²⁺ and Ca²⁺， separately. Eight peptide–metal complexes (SPIHs-Zn， CPP-Zn， ZP-Zn， AKP-Zn， SPIHs-Ca， CPP-Ca， ZP-Ca， and AKP-Ca) were successfully prepared. Fourier-transform infrared (FTIR) spectroscopy was performed to characterize the complexes. The results showed significant shifts in the characteristic absorption bands of amide I， amide II， carboxyl， and carbonyl groups， along with the narrowing of association peaks， thus confirming that the metal ions formed coordination bonds with the –CO， –NH， and –COOH groups on the peptide chains instead of undergoing physical adsorption. In-vitro simulated gastrointestinal digestion experiments demonstrated that the developed peptide–zinc/calcium complexes outperformed conventional peptide–zinc/calcium products in terms of stability and bioavailability. The findings provide a foundation for the development and application of novel zinc/calcium products.

Synthesis and application of ionic liquid

The materials which is liquid state at a temperature near the room temperature are named molten salts or ionic liquids.Over one hundred ionic liquids have been prepared.The methods of their synthesis can be classfied into two categories:metathesis and acid base neutralization.They can be applied to separation technology,electrochemistry and chemical synthesis,particularly catalytic reaction.

The evolution and advances of solid-phase microextraction

Solid-phase microextraction (SPME) is a sampling technique based on sorption of analytes onto a polymeric material coated on a silica fiber.SPME is a popular sample preparation method,which integrates extraction,concentration,desorption and injection into one step for sample preparation.SPME,which is based on solid-phase extraction (SPE),eliminates the disadvantages of using packed materials and solvents to dissolve analytes and retains all advantages of SPE.The stationary phases of SPME are polymers (such as polydimethylsiloxane) or adsorbents (such as carbon),which are coated on silica fiber or capillary column.The SPME can extract and concentrate the sample by adsorbing (or absorbing) the analytes onto stationary phases,then deliver the fiber of SPME to the inlet port of gas chromatograph for analysis.This method is suitable for sample preparation in a variety of technical areas.This paper discusses briefly the evolution and recent advances in solid-phase microextraction techniques.

Catalytic synthesis of substituted tetraphenylporphyrins

Twelve kinds of substituted tetraphenylporphyrins (TXPPH₂)were synthesized by the direct condensation of pyrrole with substituted benzaldehyde by refluxing in DMF in the presence of AlCl₃.Compared with other methods in the literature,this method has the advantages of wider applicabilities,higher yields and better purity.

Research on synthesis of new Schiff base reagent(HPMαFP)_2EN and its application in reversed-phasepaper chromatography

In this paper a new Schiff base reagent N,N'-bis[(1-phenyl-3-methyl-5-oxo-4-pyra o a-furyl-furylmethylidyne ] ethylenediimine [(HPMaFP)2EN ] hasbeen synthesized. its structure has been confirmed byelemental analysis,IR,NMR and MS. Some propertieswere determined. Its behavior in separating rare earthions has been studied by reversed-phase paper chromatography with (HPMaFP)2EN as stationary phase,acidified NawSO4 solutions as eluents. It has beenshown that this reagent can be applied to the separation of multicomponent rare earth mixtures in the PHrange of 0. 2-1. 2.

Study on the synthesis of room temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate

The key intermediate, l-butyl-3-methylimidazolium bromide, was synthesized efficiently from 1-methylimidazole and l-bromobutane.The influence of temperature and reaction heat of itself on this reaction was also investigated. After anion exchanging, room temperature ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate was obtained in 92% yield.The structure of final product was confirmed by IR and 1HNMR spectral data.

Highly Sensitive Detection of Penicillin G in Milk by Fluorescence Probe Based on Silicon Nanoparticle

The silicon nanoparticle(DFC)that emits blue fluorescence at 450 nm was synthesized by using the reagents of N-[3-(Trimethoxysilyl)propyl]ethylenediamine and fluorescein sodium salt.The structural characterization and spectral performance analysis of DFC were carried out by Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),transmission electron microscope(TEM),Zeta potential and ultraviolet-visible absorption spectrum.Based on the performance DFC can be quenched by Cr³⁺ ion, a fluorescent probe of Cr³⁺@DFC for the detection of penicillin G(PG) was prepared.The fluorescence of the Cr³⁺@DFC probe was recovered in the presence of PG.There was a good linear relationship between fluorescence recovery efficiency and PG concentration in the range of 0.1～1.0 μg/mL.The detection limit is 0.023 μg/mL,and the linear equation was y=71.26x+0.478,R²=0.99.The method is easy to operate and has high sensitivity to detect PG in milk samples, which offers a promising application prospect.

The application of 1,3-dicyclohexylcarbodiimide(DCC) used as condensation agent in organic synthesis

1,3-Dicyclohexylcarbodiimide (DCC) is widely used in the reaction for synthesis of esters and amides as a condensation agent.The synthesis and condensation reactions using DCC as the dehydration agent can take place in the mild conditions with good product yield.In this paper,DCC used as a dehydrating agent in the study on preparation of esters,amides,and phosphorylaminopropyl compounds is reviewed.

Advance in research of room temperature ionic liquids

The ionic liquids(ILs) thanks to their low melting point,high conductivity and negligible vapor pressure have been attracting great attention of the academic and industrial circles.In recent years,the ILs have widely been applied in many fields.The recent application development of ionic liquids in these fields is summarized in this paper,such as their application in chemical reactions,separation process and manufacture of new materials.The perspectives in this research field are also discussed.

Application and Progress of Fourier Transform Infrared Spectroscopy Technology

Fourier transform infrared spectroscopy(FTIR) has the advantages of fast scanning speed, high resolution and high sensitivity, and it is widely used in research fields such as mechanism research, performance characterization, and composition detection.According to different detection requirements, researchers have also made corresponding adjustments and optimizations when using FTIR.The principle of FTIR was briefly introduced, the application status of FTIR technology in various research fields in recent years was focused on.It pointed out that the combination with other analysis techniques, the establishment of mathematical models and standardization were the development trend of improving the accuracy of FTIR measurement in addition to improving the accuracy of the instrument itself, which provided a reference for the research and application of FTIR in related fields.

Determination of the Main Components of Astragalus Membranaceus and Evaluation of Their Antioxidant Activity

Twenty-four batches of A.membranaceus were extracted by ultrasound method.The contents of total saponins, total flavonoids and total polysaccharides were determined to comprehensively evaluate the effects of variety, origin and growth years on the content of various components of Astragalus membranaceus.DPPH-UHPLC-QTOF-MS/MS method was developed for screening antioxidants from A.membranaceus.DPPH and ABTS experiments were used to verify the antioxidant activity of monomer compounds.The results showed that one year A.membranaceus from Neimenggu Chifeng had the highest content of total saponins.Wild A.membranaceus from Heilongjiang Daxinanling had the highest content of total flavonoids.One year A.membranaceus from Neimenggu Wuchuan had the highest content of total polysaccharides.The results showed that flavonoids had better antioxidant activity than that of saponins and polysaccharides.By structure-activity relationship was discussed.The more hydroxyl groups attached to the flavonoids, the higher antioxidant activity they had.The attachment of glucoside to flavonoids would reduce the antioxidant activity.This study will provide theoretical basis for rational utilization of A.membranaceus and promotion of regional brand resources of A.membranaceus.