Investigation of Glycolic Acid Natural Deep Eutectic Solvents with Strong Proton Donors for Ammonia Capture and Separation

Fluorescence Detection of Pb2+ in Environmental Water Using Biomass Carbon Quantum Dots Modified with Acetamide-Glycolic Acid Deep Eutectic Solvent

In this study, a novel green fluorescent probe material, nitrogen-doped carbon quantum dots (N-CQDs), was prepared by a one-step hydrothermal synthesis method using walnut green skin as a carbon source and acetamide-glycolic acid deep eutectic solvent (AGADES) as a modifier. By covalent coupling, the amide chromophore in AGADES is designed to cover the surface of walnut green skin carbon quantum dots (W-CQDs), forming a fluorescence energy resonance effect and improving the fluorescence performance of the carbon quantum dots. The prepared N-CQDs have a uniform particle size distribution, and the fluorescence quantum efficiency has increased from 12.5% to 32.5%. Within the concentration range of 0.01~1000 μmol/L of Pb2+, the linear detection limit is 1.55 nmol/L, which can meet the trace detection of Pb2+ in the water environment, and the recycling rate reaches 97%. This method has been successfully applied to the fluorescence detection and reuse of Pb2+ in actual water bodies, providing new ideas and methods for the detection of heavy metal ions in environmental water.

Portable and reversible smart labels for non-destructive detection of seafood freshness via amine-response fluorescent ionic liquids

Herein, a functionalized ionic liquid (IL) 7-HDCP (7-hydroxycoumarin-quaternary phosphorus) was developed as NH3 trapping agents and fluorescent indicators to achieve in-time and on-site detection of seafood freshness. Interestingly, the IL displayed remarkable blue fluorescence "turn-on" enhancement to gaseous amine due to excellent amine solubility. By FTIR and 1H NMR spectrogram, this fluorescence "turn-on" phenomenon originated from the weak hydrogen bonding between the ester group of the coumarin functional group and the ammonia molecule. Moreover, the IL exhibited a rapid response (<11 s), prominent sensitivity (0.12 ppm), excellent selectivity (10 interfering substances) and outstanding reversibility (>22 cycles). Benefiting from ion characters, 7-HDCP obtained advantages of easy-to-fabricate and easy-to-use, which was fabricated by one-step simple immersion without aggregation-caused quenching phenomenon. This portable and sensitive smart label made of ion probes facilitates the timely and on-site NH3 detection in the early deterioration stages of aquatic products, enabling "early detection, early warning, and early treatment".

From Nature to Innovation: The Uncharted Potential of Natural Deep Eutectic Solvents

This review discusses the significance of natural deep eutectic solvents (NaDESs) as a promising green extraction technology. It employs the consolidated meta-analytic approach theory methodology, using the Web of Science and Scopus databases to analyze 2091 articles as the basis of the review. This review explores NaDESs by examining their properties, challenges, and limitations. It underscores the broad applications of NaDESs, some of which remain unexplored, with a focus on their roles as solvents and preservatives. NaDESs' connections with nanocarriers and their use in the food, cosmetics, and pharmaceutical sectors are highlighted. This article suggests that biomimicry could inspire researchers to develop technologies that are less harmful to the human body by emulating natural processes. This approach challenges the notion that green science is inferior. This review presents numerous successful studies and applications of NaDESs, concluding that they represent a viable and promising avenue for research in the field of green chemistry.

Physical properties of natural deep eutectic solvent and its application in remediation of heavy metal lead in soil

At present, solvent extraction is an effective method to remove heavy metals from soil, which has certain practical significance. The physical properties such as density, viscosity and conductivity of NADESs with different proportions synthesized based on the double solid components of glycolic acid (GA) and L-proline (L-PRO) and the physical properties of NADESs aqueous solution at the lowest eutectic point (3:1) were studied. The extraction effect of NADESs on soil heavy metal Pb2+ under different conditions was studied. The results showed that under the conditions of atmospheric pressure of 101.33 kPa, the lowest eutectic melting point, DESs concentration of 0.6 mol·L-1, extraction temperature of 313.15 K and extraction time of 4 h, the extraction rate of Pb2+ by NADESs was 95.28%. In addition, the internal structure of DESs was characterized by IR and NMR, which indicated that intermolecular hydrogen bonds were formed. and the interaction between DESs and Pb2+ was analyzed by quantum chemical calculation, which showed that the hydroxyl group of GA was more likely to form coordination bond with Pb2+, and chelation occurred between them. This kind of DESs provides a new idea for the removal of heavy metals in soil.

How to apply terpenoid-based deep eutectic solvents for removal of antibiotics and dyes from water: Theoretical prediction, experimental validation and quantum chemical evaluation

This study proposed a theoretical prediction method and mechanism investigation for the extraction of antibiotics and dyes from aqueous media using terpenoid-based deep eutectic solvents (DESs). Firstly, Conductor-like Screening Model for Real Solvents (COSMO-RS) approach was applied to predict selectivity, capacity and performance index in the extraction of 15 target compounds including antibiotics (tetracyclines, sulfonamides, quinolones, β-lactams) and dyes by 26 terpenoid-based DESs, and thymol-benzyl alcohol shows promising theoretical selectivity and extraction efficiency for the target compounds. Moreover, the structures of both hydrogen bond acceptors (HBA) and hydrogen bond donors (HBD) have an impact on the predicted extraction performance, which can be improved by tailoring those candidates with higher polarity, smaller molecular volume, shorter alkyl chain length and the presence of aromatic ring structures, etc. According to the predicted molecular interactions revealed by σ-profile and σ-potential, the DESs with HBD ability can promote the separation process. Furthermore, reliability of proposed prediction method was confirmed by experimental verification, indicating that the trends of theoretical extraction performance index were similar with the experimental results by using actual samples. At last, the extraction mechanism was evaluated by quantum chemical calculations based on visual presentations, thermodynamic calculations and topological properties; and the target compounds showed favorable energies of solvation to transfer from aqueous phase to DESs phase. The proposed method has been proved with potential to provide the efficient strategies and guidance for more applications (e.g., microextraction, solid phase extraction, adsorption) with similar molecular interactions of green solvents in environmental research.

Effective absorption of dichloromethane using deep eutectic solvents

Chlorinated volatile organic compounds (VOCs), of which dichloromethane (DCM) has become one of the main components because of its extensive use and strong volatility, are recognized as extremely hazardous and refractory pollutants in the atmosphere. The efficient treatment of DCM is of great significance to the protection of environment and human health. In this work, the strategy of DCM capture with deep eutectic solvents (DESs) with different hydrogen bond acceptors (HBAs) and hydrogen bond donors (HBDs) was proposed and systematically investigated. The experimental results show that tetrabutylphosphonium chloride: levulinic acid ([P₄₄₄₄][Cl]-LEV) presents the most excellent DCM absorption capacity among all DESs studied and considerable capacity in [P₄₄₄₄][Cl]-LEV (1:2) with 899 mg DCM/g DES (5.58 mol DCM/mol DES) at 30 °C and DCM partial pressure of 0.3 bar can be achieved. The microscopic absorption mechanism is explored by ¹HNMR and FT-IR spectra as well as quantum chemistry calculations, indicating that the absorption is a physical process. The interaction energy analysis suggests that the greater the interaction energy between DES and DCM, the greater the saturated absorption capacity of DCM. The hydrogen bond (HB) contributes most to the weak interaction between DCM and HBA/HBD, and both HBA and HBD play an important role in the absorption of DCM.

Efficient and reversible absorption of low pressure NH3 by functional type V deep eutectic solvents based on phenol and hydroxypyridine

Highly efficient and reversible absorption of low pressure ammonia by phenol-hydroxypyridine deep eutectic solvents.

Highly efficient and reversible adsorption of ammonia by incorporation of deep eutectic solvents into silica gel and Al2O3

The uptake of NH3 in the industrial tail gas will improve environmental quality for human health and ecology. Adsorption separation has the advantages of simple operation and low energy consumption....