Hydrophobic magnetic deep eutectic solvent: Synthesis, properties, and application in DNA separation

Trioctylphosphine oxide-based hydrophobic magnetic deep eutectic solvent as a novel extractant for the enrichment of primary aromatic amines from juice and environmental water

In this study, a novel technique utilizing vortex-assisted dispersive liquid-liquid microextraction with magnetic deep eutectic solvents (MDESs) was established and coupled with HPLC-UV to analyze six primary aromatic amines (PAAs). A novel hydrophobic MDES prepared from trioctylphosphine oxide, octanol, and CoCl2 was used as the extractant, which could be dispersed uniformly during extraction, then floated onto the sample surface and re-aggregated into a single drop spontaneously after the extraction. The variables influencing the efficiency of the extraction process were investigated. When performing under the optimal extraction conditions, this method exhibited excellent linearity, low limits of detection (0.2-0.9 ng mL-1), and high precision (RSD ≤ 8.3 %). The enrichment factors ranged from 56 to 182. Satisfactory recoveries in the range of 91.6-109.2 % with RSDs < 7.1 % were obtained from three apple juices and three environmental water samples. The greenness and practicality of the developed method were assessed by AGREE, AGREEprep, and blue applicability grade index metric tools. Overall, the established procedure demonstrated its simplicity, speediness, environmental friendliness, and effectiveness in analyzing PAAs from aqueous matrices.

An optimal genomic DNA extraction method for shoots of four Dendrocalamus species based on membership function analysis

High-quality genomic DNA extraction is fundamental for the study of gene cloning and expression in plants. Therefore, this study evaluated several methods for extracting genomic DNA from shoots of four Dendrocalamus species to determine the optimal technique. Genomic DNA was extracted using three different methods: a commercial DNA extraction kit method, a modified cetyltrimethylammonium bromide method and a sodium dodecyl sulfate method. A membership function analysis was employed to compare these methods. The results demonstrated that the commercial DNA extraction kit method was the most effective and comprehensive approach for extracting genomic DNA from shoots of four Dendrocalamus species. Furthermore, this study provided valuable insights into optimizing techniques for extracting genomic DNA in other bamboo species.

Ultrasonic-assisted extraction of flavonoids from peanut leave and stem using deep eutectic solvents and its molecular mechanism

Natural bioactive compounds extracted from agricultural by-products have received considerable attentions. Twenty-two kinds of deep eutectic solvents (DESs) with ultrasonic were screened to extract flavonoids from peanut leave and stem. ChCl-acetic acid (ChCl-Aa) with 1:2 M ratio resulted in more effective extraction of flavonoids compared to other solvents The best extraction conditions were found to be at a 27% water content in DES/H2O, for 43 min with 31:1 g/mL liquid/solid ratio, giving 2.980 mg/g dw of flavonoids through the response surface method. SEM showed that ChCl-Aa had a certain dissociation impact on the sample matrix, while 1H NMR analysis revealed the formation of hydrogen bonds between daidzein and ChCl-Aa. Changes in the H-bond length and number were observed by the B3LYP/6-31G (d,p) level of theory to confirm the experimental spectra. This study reveals that DESs are efficient for obtaining value-added products and could applied to other natural products.

Deep eutectic solvents with solid supports used in microextraction processes applied for endocrine-disrupting chemicals

The determination of endocrine-disrupting chemicals (EDCs) has become one of the biggest challenges in Analytical Chemistry. Due to the low concentration of these compounds in different kinds of samples, it becomes necessary to employ efficient sample preparation methods and sensitive measurement techniques to achieve low limits of detection. This issue becomes even more struggling when the principles of the Green Analytical Chemistry are added to the equation, since finding an efficient sample preparation method with low damaging properties for health and environment may become laborious. Recently, deep eutectic solvents (DESs) have been proposed as the most promising green kind of solvents, but also with excellent analytical properties due to the possibility of custom preparation with different components to modify their polarity, viscosity or aromaticity among others. However, conventional extraction techniques using DESs as extraction solvents may not be enough to overcome challenges in analysing trace levels of EDCs. In this sense, combination of DESs with solid supports could be seen as a potential solution to this issue allowing, in different ways, to determine lower concentrations of EDCs. In that aim, the main purpose of this review is the study of the different strategies with solid supports used along with DESs to perform the determination of EDCs, comparing their advantages and drawbacks against conventional DES-based extraction methods.

Magnetic deep eutectic solvent-based dispersive liquid-liquid microextraction for determination of strobilurin fungicides in water, juice, and vinegar by high-performance liquid chromatography

In this study, a magnetic deep eutectic solvent coupled with dispersive liquid-liquid microextraction using high-performance liquid chromatography (MDES-DLLME-HPLC) was developed to detect strobilurin fungicides. The green hydrophobic MDES synthesized by methyltrioctylammonium chloride, ferric chloride, and heptanoic acid was used as an extraction solvent, which was dispersed by vortex and separated by an external magnetic field. The use of toxic solvents was avoided, and the separation time was reduced. The best experimental results were obtained through single factor and response surface optimization. The method had a good linear relationship with R² > 0.996. The limit of detection (LOD) ranged from 0.001 to 0.002 mg L^-1. The extraction recoveries were 81.9-108.9%. The proposed method was rapid and green, and it has been successfully applied to detection of strobilurin fungicides in water, juice, and vinegar.

Deep eutectic solvent-based manganese dioxide nanosheets composites for determination of DNA by a colorimetric method

BACKGROUND

Nucleic acid is the carrier of genetic information and the keymolecule in life science. It is important to establish a simple and feasible method for nucleic acid quantification in complex biological samples.

METHODS

Four kinds of hydrogen bond acceptors (choline chloride (ChCl), L-carnitine, tetrabutylammonium chloride (TBAC) and cetyltrimethylammonium bromide (CTAB)) were used to synthesize deep eutectic solvents (DESs) with hexafluoroisopropanol (HFIP). DESs based manganese dioxide (MnO2) nanosheets composites was synthesized and characterized. DNA concentration was determined by a UVVis spectrometer. The mechanism of DNA-DES/MnO2 colorimetric system was further discussed.

RESULTS

The composite composed of DES/MnO2 exhibited excellent oxidase-like activity and could oxidize 3,3',5,5' -tetramethylbenzidine (TMB) to produce a clear blue change with an absorbance maximum at 652 nm. When DNA is introduced, the DNA can interact with the DES by hydrogen bonding and electrostatic interactions, thereby inhibiting the color reaction of DES/MnO2 with TMB. After condition optimization, ChCl/HFIP DES in 1:3 molar ratio was used for the colorimetric method of DNA determination. The linear range of DNA was 10-130 µg/mL and exhibited good selectivity.

CONCLUSION

A colorimetric method based on DES/MnO2 was developed to quantify the DNA concentration. The proposed method can be successfully used to quantify DNA in bovine serum samples.

Hexafluoroisopropanol-based deep eutectic solvents for high-performance DNA extraction†

In this study, hexafluoroisopropanol (HFIP)-based deep eutectic solvents (DESs) were developed and used for DNA extraction from human whole blood samples for the first time. HFIP-based DESs were prepared using HFIP and choline chloride (ChCl)/tetrabutylammonium chloride/cetyltrimethylammonium bromide as the hydrogen bond donor and acceptor, respectively. The two-phase system formation was promoted with different inorganic salts as the phase-forming component. According to the strong phase separation capability and high DNA extraction efficiency, DESs consisting of HFIP/ChCl-(NH₄)₂SO₄, HFIP/ChCl-Na₂SO₄ and HFIP/ChCl-MgSO₄ were then selected for application in DNA extraction. The factors that could have impacted the DNA extraction process, including molar ratio of DES, DES addition, salt species and addition, and sample pH, were systematically investigated via single-factor experimental analysis. Furthermore, we selectively examined bovine serum albumin and RNA to assess the specificity of the HFIP-based DESs for DNA extraction. Conclusively, 93.9%, 96.7% and 99.8% DNA could be extracted using the HFIP/ChCl-(NH₄)₂SO₄, HFIP/ChCl-Na₂SO₄, and HFIP/ChCl-MgSO₄ systems, respectively. Moreover, the developed systems were successfully used to extract DNA from human whole blood with satisfactory results. The DNA secondary structure was stable after DES extraction with the electrostatic interaction between DES and DNA as the main force driving DNA adsorption by DES.

In a novel approach, hexafluoroisopropanol-based deep eutectic solvents were synthesized and utilized as an efficient alternative for extracting DNA from human whole blood.