An environment-friendly and rapid liquid-liquid microextraction based on new synthesized hydrophobic deep eutectic solvent for separation and preconcentration of erythrosine (E127) in biological and pharmaceutical samples

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.

Carbon nanotubes: a novel innovation as food supplements and biosensing for food safety

Recently, nanotechnology has emerged as an extensively growing field. Several important fabricated products including Carbon nanotubes (CNTs) are of great importance and hold significance in several industrial sectors, mainly food industry. Recent developments have come up with methodologies for the prevention of health complications like lack of adequate nutrition in our diet. This review delves deeper into the details of the food supplementation techniques and how CNTs function in this regard. This review includes the challenges in using CNTs for food applications and their future prospects in the industry. Food shortage has become a global issue and limiting food resources put an additional burden on the farmers for growing crops. Apart from quantity, quality should also be taken into consideration and new ways should be developed for increasing nutritional value of food items. Food supplementation has several complications due to the biologically active compounds and reaction in the in vivo environment, CNTs can play a crucial role in countering this problem through the supplementation of food by various processes including; nanoencapsulation and nanobiofortification thus stimulating crop growth and seed germination rates. CNTs also hold a key position in biosensing and diagnostic application for either the quality control of the food supplements or the detection of contagions like toxins, chemicals, dyes, pesticides, pathogens, additives, and preservatives. Detection such pathogens can help in attaining global food security goal and better production and provision of food resources. The data used in the current review was collected up to date as of March 31, 2024 and contains the best of our knowledge. Data collection was performed from various reliable and authentic literatures comprising PubMed database, Springer Link, Scopus, Wiley Online, Web of Science, ScienceDirect, and Google Scholar. Research related to commercially available CNTs has been added for the readers seeking additional information on the use of CNTs in various economic sectors.

Developing of an eco-friendly liquid-liquid microextraction method by using menthol-based hydrophobic deep eutectic solvent for determination of basic fuchsin dye: assessment of the greenness profile

Herein, we aimed to develop a new environmentally friendly liquid-liquid microextraction (LLME) method based on hydrophobic deep eutectic solvent (hDES) synthesized using biodegradable dl-menthol and decanoic acid for the spectrophotometric determination of toxic basic fuchsin dye in environmental water samples. The parameters affecting the extraction efficiency such as pH, mole ratio, and volume of hDES (1:2) and type and volume of organic solvent, sample volume, times of vortex, ultrasonic bath and centrifuge, ionic strength, and matrix effect were investigated and optimized. Under optimal conditions, the calibration curve showed linearity in the range of 7.4-167 μg L-1 with a coefficient of determination of 0.9994. The limit of detection, intra-day and inter-day precision, and recovery values were 2.25 μg L-1, 2.46% and 4.45%, and 105 ± 3%, respectively. The preconcentration and enrichment factors were found to be 30 and 61.5, respectively. The proposed hDES-LLME methodology was successfully applied to the environmental water samples to detect toxic BF dye (95-105%). Finally, the ecological impact of the suggested method was evaluated using the analytical eco-scale (PPS:88), complementary green analytical procedure indexe (ComplexGAPI), and the Analytical GREEnness tool (0.63). The assessment results showed that the presented analytical method can be regarded as a green LLME approach for the determination of the BF in water.

A hydrophobic deep eutectic solvent-based microextraction for the determination of ultra-trace arsenic in foods by an electrothermal atomization atomic absorption spectrometry

A hydrophobic deep eutectic solvent-based liquid-phase microextraction approach for the determination of ultra-trace arsenic (total) in foods by an electrothermal atomization atomic absorption spectrometry was developed. Various deep eutectic solvents based on tetraoctylammonium bromide and fatty acids (heptanoic, octanoic, nonanoic, decanoic acids) were studied as extraction solvents for preconcentration of arsenic (V) from mineralizates obtained after a microwave digestion of food samples. Phenomenon of ion-pairs formation between dihydroarsenate and precursor of deep eutectic solvent (tetraoctylammonium) and mass-transfer of the ion-pairs into deep eutectic solvent phase was presented for the first time. The proposed approach allowed to preconcentrate analyte into the deep eutectic solvent phase without the use of additional organic solvents (emulsifier agents or dispersive solvent), chelating and reducing agents. It was found, that the deep eutectic solvent based on tetraoctylammonium bromide and heptanoic acid provided more effective preconcentration of analyte from mineralizates (95% extraction recovery, 57-fold enrichment factor). The obtained limit of detection, calculated as a triple signal-to-noise ratio, was 10 ng L-1. The microextraction procedure was applied for the determination of trace arsenic in rice and wheat grains samples.

Hydrophobic Deep Eutectic Solvents as Greener Substitutes for Conventional Extraction Media: Examples and Techniques

Deep eutectic solvents (DESs) are multicomponent designer solvents that exist as stable liquids over a wide range of temperatures. Over the last two decades, research has been dedicated to developing noncytotoxic, biodegradable, and biocompatible DESs to replace commercially available toxic organic solvents. However, most of the DESs formulated until now are hydrophilic and disintegrate via dissolution on coming in contact with the aqueous phase. To expand the repertoire of DESs as green solvents, hydrophobic DESs (HDESs) were prepared as an alternative. The hydrophobicity is a consequence of the constituents and can be modified according to the nature of the application. Due to their immiscibility, HDESs induce phase segregation in an aqueous solution and thus can be utilized as an extracting medium for a multitude of compounds. Here, we review literature reporting the usage of HDESs for the extraction of various organic compounds and metal ions from aqueous solutions and absorption of gases like CO₂. We also discuss the techniques currently employed in the extraction processes. We have delineated the limitations that might reduce the applicability of these solvents and also discussed examples of how DESs behave as reaction media. Our review presents the possibility of HDESs being used as substitutes for conventional organic solvents.

Facile liquid colorimetric sensor using high-density deep eutectic solvent for trace detection and speciation of iron in milk

An efficient colorimetric sensor was developed using a high-density deep eutectic solvent (HD-DES) for the trace detection and speciation of iron in various milk samples. A liquid colorimetric probe was fabricated by dissolving ferrozine (FZ) in HD-DES prepared from TBABr and PBA. The prederivatization of Fe²⁺ via complexation with FZ on the HD-DES/FZ probe provided the [Fe(FZ)₃]^4- complex, which led to a color change from pale yellow to purple before it was simultaneously extracted by HD-DES. The Fe³⁺ content was calculated by subtracting the amount of Fe²⁺ from the total Fe content following the reduction of Fe³⁺ to Fe²⁺ by L-ascorbic acid in an acid buffer. Under the optimized conditions, the proposed colorimetric sensor exhibited appreciable linearity in the concentration range of 0.003-0.04 mg L^-1, a low limit of detection (0.95 µg L^-1), high enrichment factor (50), and outstanding repeatability. The liquid colorimetric probe was successfully applied for the determination and speciation of iron in milk samples, and the results were compared with those obtained using the standard atomic absorption spectrometry method. Moreover, quantitative analysis was performed on a smartphone using the Image J application to estimate the color intensity change, which eliminated the requirement of sophisticated scientific instruments.

Ultrasound assisted supramolecular liquid phase microextraction procedure for Sudan I at trace level in environmental samples

A method based on supramolecular liquid phase microextraction has been developed for the preconcentration and determination of trace levels of Sudan I. 1-decanol and tetrahydrofuran were used as supramolecular solvent components. Trace levels of Sudan I were extracted into the extraction solvent phase at pH = 4.0 Analytical parameters such as pH value, supramolecular solvent volume, ultrasonication, centrifugation, model solution volume, matrix effects have been optimized. The limit of detection and the limit of quantification values for Sudan I were calculated as 1.74 μg L⁻¹ and 5.75 μg L⁻¹, respectively. In order to determine the accuracy of the method, addition and recovery studies were carried out to environmental samples.

Determination of prohibited lead and cadmium traces in hair dyes and henna samples using ultrasound assisted-deep eutectic solvent-based liquid phase microextraction followed by microsampling-flame atomic absorption spectrometry

In this study ultrasound assisted-deep eutectic solvent-based liquid phase microextraction followed by microsampling-flame atomic absorption spectrometry was developed to determine prohibited lead and cadmium traces in hair dye and henna samples. For this purpose, deep eutectic solvent, prepared from choline chloride and phenol, was used as an extraction solvent, dithizone was used as a complexing agent, and THF was used as an aprotic solvent. All parameters that affect extraction efficiency, such as pH, the DES volume and composition, the extraction time, the amount of dithizone, were optimized. Under the optimal conditions, for Pb(ii) and Cd(ii), enhancement factors of 92 and 57, LODs of 2.5 μg L^-1 and 0.75 μg L^-1, LOQs of 7.8 μg L^-1 and 2.5 μg L^-1, linear working ranges of 10-250 μg L^-1 and 2.5-50 μg L^-1, were obtained, respectively. Relative standard deviation (n = 10) was calculated to be 2.7 for 100 μg L^-1 of Pb(ii) and 2.1 for 25 μg L^-1 of Cd(ii). The matrix effect was investigated by comparing the solvent-based calibration curve with the matrix-matched calibration curve. The determination of lead and cadmium in hair dye and henna samples without being affected by the sample matrix was successfully performed. The lead content was between 1.3 and 6.5 μg g^-1, and the cadmium content was between 0.028 and 0.54 μg g^-1 for the selected hair dye and henna samples.

Effervescence-Assisted Microextraction-One Decade of Developments

Dispersive microextraction techniques are key in the analytical sample treatment context as they combine a favored thermodynamics and kinetics isolation of the target analytes from the sample matrix. The dispersion of the extractant in the form of tiny particles or drops, depending on the technique, into the sample enlarges the contact surface area between phases, thus enhancing the mass transference. This dispersion can be achieved by applying external energy sources, the use of chemicals, or the combination of both strategies. Effervescence-assisted microextraction emerged in 2011 as a new alternative in this context. The technique uses in situ-generated carbon dioxide as the disperser, and it has been successfully applied in the solid-phase and liquid-phase microextraction fields. This minireview explains the main fundamentals of the technique, its potential and the main developments reported.

Microextraction Techniques with Deep Eutectic Solvents

In this review, the ever-increasing use of deep eutectic solvents (DES) in microextraction techniques will be discussed, focusing on the reasons needed to replace conventional extraction techniques with greener approaches that follow the principles of green analytical chemistry. The properties of DES will be discussed, pinpointing their exceptional performance and analytical parameters, justifying their current extensive scientific interest. Finally, a variety of applications for commonly used microextraction techniques will be reported.