Microwave-assisted micellar extraction of organic and inorganic iodines using zwitterionic surfactants

Preconcentration of Heterocyclic Aromatic Amines in Edible Fried Insects Using Surfactant-Assisted Hydrophobic Deep Eutectic Solvent for Homogeneous Liquid-Liquid Microextraction prior to HPLC

Thermal processing techniques are often accompanied by the production of many harmful compounds such as heterocyclic aromatic amines (HAAs). To protect human health, an efficient and environmentally friendly method, namely, homogeneous liquid-liquid microextraction (HLLME), was investigated. This method is based on a surfactant-assisted hydrophobic deep eutectic solvent for the determination of HAAs in edible fried insect samples prior to their analysis by high-performance liquid chromatography coupled with UV detection. A hydrophobic deep eutectic solvent (as extraction solvent) was synthesized using decanoic acid as a hydrogen bond donor and tetrabutylammonium bromide (TBABr) as a hydrogen bond acceptor and then characterized by Fourier transform infrared (FTIR) spectroscopy. The surfactant was used as the emulsifier and induces mass transfer, resulting in an increasing extraction efficiency of the proposed method. Various factors affecting the extraction performance were investigated and optimized. A matrix-match calibration method was used to analyze HAAs in high heat-treated edible fried insect samples. Under optimized conditions, the proposed method showed good linearity (R2 ≥ 0.99) with satisfactory limits of detection and satisfactory reproducibility with relative standard deviation of less than 10.0%. Furthermore, the procedure greenness was assessed using the Analytical Eco-Scale. This paper represents the first application of HLLME based on a surfactant-assisted hydrophobic deep eutectic solvent to analyze HAAs in edible fried insect samples.

Cucurbituril and zwitterionic surfactant-based matrix solid-phase dispersion microextraction to simultaneously determine terpenoids from Radix Curcumae

A rapid, efficient, and environmentally friendly matrix solid-phase dispersion microextraction was established to determine and quantify terpenoids in Radix Curcumae using ultra-high-performance liquid chromatography with a diode array detector. Various parameters affecting the extraction were investigated in detail, such as the grinding time, amount of adsorbent, type and concentration of elution solvent, and pH. The optimization of single-factor and response surface methodology was performed to confirm the best conditions in this procedure. The final optimized conditions were obtained by applying 70 mg of cucurbituril as adsorbent, 149 s as the optimum grinding time, and 228 mM of 3-(N,N-dimethylpalmitylammonio)propanesulfonate aqueous solution (pH 6.5) as the optimal elution solvent. The validated method showed a satisfactory linear range of 0.10-10 µg/mL for curdione and furanodiene, 0.01-10 µg/mL for isocurcumenol and germacrone, and 0.05-10 µg/mL for furanodienone, while the correlation coefficients ranged from 0.9945 to 0.9970. The recoveries of the investigated analytes at two spiked concentration levels (0.1 and 1.0 µg/mL) ranged from 96.53 to 104.60%. In addition, this method displayed acceptable reproducibility (relative standard deviation ≤ 3.66%). The results showed that the newly proposed matrix solid-phase dispersion microextraction method was successfully applied to analyze curdione, isocurcumenol, furanodienone, germacrone and furanodiene in Radix Curcumae samples.

An Eco-Friendly Hydrophobic Deep Eutectic Solvent-Based Dispersive Liquid-Liquid Microextraction for the Determination of Neonicotinoid Insecticide Residues in Water, Soil and Egg Yolk Samples

A green, simple and sensitive hydrophobic DES-based dispersive liquid–liquid microextraction coupled with high-performance liquid chromatography (HPLC) was developed for the analysis of neonicotinoid insecticide residues in various samples. A hydrophobic deep eutectic solvent (DES) was synthesized using decanoic acid as a hydrogen bond donor and tetrabutylammonium bromide (TBABr) as a hydrogen bond-acceptor. DESs were synthesized and characterized by Fourier transform-infrared (FTIR) spectroscopy. Two disperser solvents were substituted with surfactants and acetonitrile, which could afford more effective emulsification and make the extraction relatively greener. The hydrophobic DES extraction phase occurred 10 min after centrifugation, being easy to be collected for analysis. Several parameters were investigated and optimized. Under the optimum condition, the calibration curve of this method was linear in the range of 0.003–1.0-µg·mL⁻¹, with a correlation coefficient (R²) higher than 0.99 and a good repeatability, with the relative standard deviations (RSDs) were less than 5.00%. The limits of detection were in the range of 0.001–0.003 µg·mL⁻¹; the limits of quantitation were in the range of 0.003–0.009 µg·mL·mL⁻¹. Finally, the presented method was implemented to determine the neonicotinoid insecticide residues in water, soil, egg yolk samples and acceptable recoveries were obtained.

Biosurfactant trehalose lipid-enhanced ultrasound-assisted micellar extraction and determination of the main antioxidant compounds from functional plant tea

Hydrosoluble trehalose lipid (a biosurfactant) was employed for the first time as a green extraction solution to extract the main antioxidant compounds (geniposidic acid, chlorogenic acid, caffeic acid, and rutin) from functional plant tea (Eucommia ulmoides leaves). Single-factor tests and response surface methodology were employed to optimize the extraction conditions for ultrasound-assisted micellar extraction combined with ultra-high-performance liquid chromatography in succession. A Box-Behnken design (three-level, three-factorial) was used to determine the effects of extraction solvent concentration (1-5 mg/mL), extraction solvent volume (5-15 mL), and extraction time (20-40 min) at a uniform ultrasonic power and temperature. In consequence, the best analyte extraction yields could be attained when the trehalose lipid solution concentration was prepared at 3 mg/mL, the trehalose lipid solution volume was 10 mL and the extraction time was set to 35 min. In addition, the recoveries of the antioxidants from Eucommia ulmoides leaves analyzed by this analytical method ranged from 98.2 to 102%. These results indicated that biosurfactant-enhanced ultrasound-assisted micellar extraction coupled with a simple ultra-high-performance liquid chromatography method could be effectively applied in the extraction and analysis of antioxidants from Eucommia ulmoides leaf samples.

Ecofriendly microwave-assisted reaction and extraction of bioactive compounds from hawthorn leaf

INTRODUCTION

The main active components in hawthorn leaves possess various biological activities such as anti-inflammatory, antioxidant, and hypolipidemic effects. Therefore, it is necessary to develop an effective and reliable extraction method to extract these active compounds from hawthorn leaves.

OBJECTIVE

To establish a simple, rapid, and sensitive method for extraction and determination of polyphenolic compounds from hawthorn leaves.

METHODS

In this study, a microwave-assisted reaction and extraction (MARE) combined with ultra-high-performance liquid chromatography with ultraviolet detector method was established to extract and determine the polyphenolic compounds in hawthorn leaves. The solid reagent aqueous solutions were applied as extraction solvents, preventing the use of organic solvents. The target analytes were identified by quadrupole time-of-flight tandem mass spectrometry. Several experimental parameters that can significantly affect the extraction efficiency were evaluated and optimised.

RESULTS

The optimal conditions were as follows: 0.1 g of sodium carbonate was used as solid reagent, the amount of sodium borate was set at 0.01 g, extraction time was 10 min, extraction temperature was set at 50°C, pH value was adjusted to 7. The validation experiments demonstrated that the method had high sensitivity with the limits of detection in the range 26.5-37.7 ng/mL. The average recoveries ranged from 80.22% to 93.27%.

CONCLUSION

In this work, the proposed MARE method was successfully applied to extract and determine polyphenolic compounds in hawthorn leaf samples. Compared with other reported methods, the present method was faster, greener, and more sensitive.