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A streamlined experimental protocol has been developed for rapid on-site detection, combining in-capillary aptamer-functionalized solid-phase microextraction, extraction nanoelectrospray ionization, and miniature mass spectrometry analysis.

Green analytical chemistry aims at developing analytical methods with minimum use and generation of hazardous substances for the protection of human health and the environment. To address this need, a green analytical protocol has been developed for the analysis of anionic compounds integrating electromembrane extraction (EME), dual-channel nanoelectrospray ionization (nanoESI), and a miniature mass spectrometer. Haloacetic acids (HAAs) have attracted considerable public concern due to their adverse effects on human health and were selected as model analytes for method development. A flat membrane EME device was developed and assembled in-house. Optimization of fundamental operational parameters was performed using single-factor test and response surface methodology. Both the EME acceptor phase and an imidazolium-based dicationic ionic liquid (DIL), 1,1-bis(3-methylimidazolium-1-yl) butylene difluoride (C

The reliable identification of fentanyl and its analogs is of great significance for public security. However, with the growing prevalence of fentanyl compounds, current analytical strategies cannot fully meet the need for fast and high-throughput detection. In this study, a simple, rapid, and on-site analytical protocol was developed based on a miniature mass spectrometer. A dramatically simplified workflow was implemented using matrix-assisted ionization, bypassing complex sample pretreatment and chromatographic separation. The tandem mass spectrometry (MS/MS) capability afforded by the miniature ion trap mass spectrometer facilitated the investigation of fragmentation patterns for 49 fentanyl analogs during collision-induced dissociation, revealing valuable information on marker fragment ions and characteristic neutral loss. Calculations on Laplacian bond order values further verified the mass spectrometric behavior. A computation-assisted expandable mass spectral library was constructed in-house for fentanyl compounds. Smart suspect screening was carried out based on the full-scan MS and MS/MS data. The present study demonstrates an appealing potential for forensic applications, enabling streamlined screening for the presence of illicit fentanyl compounds at the point of seizures of suspect samples.

N-methylpyrrolidinium-based ionic liquid, with fluorine function group, N-(2-fluoroethyl) N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide is proposed as the co-solvent for Si anode. Scanning electron microscope, X-ray photoelectron spectroscopy as well as the impedance measurement is conducted to investigate its effect on the solid electrolyte interface formation. Cycling tests show that it can much better improve the cycling stability of Si than fluoroethylene carbonate or F-free ionic liquid analogue.

Pomegranate fruit has shown a variety of pharmacological effects, however, the bioactive constituents in pomegranate seeds have not been fully identified. To this end, the chemical compositions of pomegranate seeds were analyzed using ultra-high-performance liquid chromatography (UHPLC) coupled with quadrupole-Orbitrap high-resolution mass spectrometry (Q-Orbitrap HRMS). Prior to analysis, pomegranate seed samples were treated by ultrasonic/microwave-assisted extraction (UMAE). A total of 88 chemical compounds were tentatively identified based on accurate-mass measurements for precursor and fragment ions, including flavonoids, coumarins, phenolic acids, amino acids, and nucleosides. Their mass spectrometric fragmentation pathways were investigated. The study has revealed the nutritional value of pomegranate seeds, paving the way for future further applications of pomegranate seeds in nutrition and health care industry.

A highly efficient and selective method for esterification of formic and acetic acid with alcohols has been achieved at room temperature, with the choline chloride (ChCl)/chromium(III) chloride hexahydrate (CrCl3·6H2O) deep eutectic solvent as a catalyst. High yields and good selectivities of organic esters are obtained using DES [ChCl][CrCl3·6H2O]2 with the molar ratio 5 : 1 (carboxylic acids : alcohols) at room temperature in 24 h. The ease of recovery and reusability of DES with high catalytic activity makes this method efficient and practical.

A novel and distinct method of preparing pillar[5]arene and pillar[6]arene with high selectivity and efficiency has been achieved by condensation of 1,4-dialkoxybenzene and paraformaldehyde with the choline chloride (ChCl)/ferric chloride (FeCl3) deep eutectic solvent in CH2Cl2 at room temperature. Under the optimal conditions, the yield of pillar[5]arene and pillar[6]arene is 35% and 53%, respectively. The reaction mechanism is investigated by room-temperature X-band Electron Spin Resonance (ESR), indicating that a free radical takes part in this cyclization reaction and acts as an intermediate. Our research is the first report about the application of DESs in supramolecular macrocyclic host synthesis.

NaOH/urea aqueous solution is a novel, green solvent for cellulose. To explain why cellulose just be dissolved in this solvent under −13 °C, we studied and discussed the dissolving process of cellobiose in water, urea solution, NaOH solution and NaOH/urea aqueous solution. Dissolving cellobiose in water and the urea solution absorb heat, which is an entropy-driven process. Dissolving cellobiose in NaOH solution and mixed NaOH/urea solution is exothermic, which is an enthalpy-driven process. OH− plays an important role in the dissolving process by forming a hydrogen-bonding complex. From the thermodynamic point of view, negative entropy can well interpret why cellulose must be dissolved in cold NaOH/urea aqueous solution.

In order to reduce CO2 accumulation in the atmosphere, chemical fixation methodologies were developed and proved to be promising. In general, CO2 was turned into cyclic carbonates by cycloaddition with epoxides. However, the cyclic carbonates need to be converted into open-chained carbonates by transesterification for industrial usage, which results in wasted energy and materials. Herein, we report a process catalyzed by tetramethylguanidine (TMG) to afford linear carbonates directly. This process is greener and shows potential for industrial applications.

Herein, we report an effective synthesis of cyclic carbonates by cycloaddition of carbon dioxide to epoxide using a modified amino acid ionic liquid as catalyst under 1 atm pressure. With triethylamine as co-catalyst, the catalytic activity of the l-proline based ionic liquid was greatly enhanced, and up to 97 % isolated yield of cyclic carbonate was achieved at 90°C under atmospheric pressure without organic solvent and metal component.