Tetrabutylammonium Bromide Research Articles

Development and Factorial Experimental Design Optimization of Deep Eutectic Solvent‐Based Microextraction of Carmoisine (E122) in Candy and Water Samples

A new deep eutectic solvent-based liquid phase microextraction (DES-LPME) method was developed and used to separate and enrich Carmoisine (E122). The deep eutectic solvent containing tetrabutylammonium bromide (TBABr) and decanoic acid (DA) was prepared and employed with multivariate statistical design for the optimization of the spectrophotometric analysis conditions to determine carmoisine in the extractant phase. The optimized limit of detection (LOD), limit of quantification (LOQ), and preconcentration factor were 3.3 µg L−1, 11.1 µg L−1, and 10, respectively. The advantages of this approach are low solvent consumption and rapid analysis. The method analyzed candy and water samples with recoveries from 94% to 108%.

Electrospun nanofiber mats as sorbents for polar emerging organic contaminants: Demonstrating tailorable material performance for uptake of neonicotinoid insecticides from water

The number and diversity of chemical contaminants in aquatic environments require versatile technologies for their removal. Here we fabricated various electrospun nanofiber mats (ENMs) and tested their ability to sorb six neonicotinoid insecticides, a model family of small, polar contaminants. ENM formulations were polyacrylonitrile (PAN) or carbon nanofibers (CNF; carbonized from PAN), with additives including carbon nanotubes (CNTs; with and without surface carboxyl groups), the cationic surfactant tetrabutyl ammonium bromide (TBAB), and/or phthalic acid (PTA; a CNF porogen). While sorption on pure PAN ENMs was low [equilibrium partition coefficients (KENM-W) from 0.9 to 1.2 log units (L/kg)], inclusion of CNTs and/or TBAB generally increased uptake in an additive fashion, with carboxylated CNT composites outperforming non-functionalized CNT analogs. CNF ENMs exhibited as much as a tenfold increase relative to PAN for neonicotinoid sorption, which increased with carbonization temperature. Ultimately, the optimal ENM (CNFs with carboxylated-CNTs, PTA, and carbonized at 800 °C) exhibited relatively fast uptake (equilibrium < 1 day without mixing) and surface-area-normalized capacities comparable to other carbonaceous sorbents (e.g., activated carbon). Collectively, this work demonstrates the versatility of electrospinning to produce novel sorbents specifically designed to target emerging chemical classes for applications including water treatment and passive sampling.

Limonene carbonate synthesis from CO2: Continuous high-pressure flow catalysis with integrated product separation

In this work, a proof-of-concept of a continuous flow process for the synthesis of limonene carbonate (LC) from the cycloaddition reaction between CO2 and limonene oxide (LO) was explored. The process uses a biphasic system composed of a CO2 mobile-phase and a stationary ionic liquid (IL)-phase used as the reaction catalyst. To determine the best conditions for integrating reaction and separation steps, high-pressure phase behaviour studies of the binary mixtures CO2 +LO and CO2 +LC were performed. The continuous process was carried out at a pressure of 300 bar and temperatures of 100 ºC, 120 ºC and 140 ºC, using two different ILs as catalysts, namely tetrabutylammonium bromide (TBABr) and trioctylmethylammonium chloride (Aliquat Cl). Results showed that at lower temperature conditions it was possible to continuously carry out the reaction for 45 h with moderate yields. TBABr revealed to be a more stable catalytic phase when compared with Aliquat Cl.

Palladium-Catalyzed Synthesis of Novel Quinazolinylphenyl-1,3,4-thiadiazole Conjugates

Two novel series of symmetrical and unsymmetrical conjugates, in which 1,3,4-thiadiazole and 4-N,N-dimethylaminoquinazoline scaffolds were connected via 1,4-phenylene linker, were synthetized in high yields by Suzuki cross-coupling reactions. The elaborated protocol makes use of bromo-substituted quinazolines, boronic acid pinacol ester or diboronic acid bis(pinacol)ester of 2,5-diphenyl-1,3,4-thiadiazole, catalytic amounts of [1,10-bis(diphenylphosphino)ferrocene]dichloropalladium(II) Pd(dppf)Cl2, sodium carbonate, and tetrabutylammonium bromide, which plays the role of a phase-transfer catalyst. The structures of prepared compounds were confirmed by 1H NMR, 13C NMR, UV-VIS, IR and HRMS. For the target compounds, the fluorescence spectra were measured to determine their quantum yields and Stokes shifts. The study revealed that among the tested compounds, two highly-conjugated derivatives (8a, 9a), in which 1,3,4-thiadiazole core is connected to 4-(N,N-dimethylamino)quinazoline via a double 1,4-phenylene linker, exhibit high quantum yields of fluorescence and strong fluorescence emission.

A novel method to store methane by forming hydrate in the high water-oil ratio emulsions

Natural gas (NG) storage in the form of clathrate hydrates gains much attention due to their non-explosive and eco-friendly characteristics. This study developed a novel method to store methane by forming hydrate in the high water cut (40–100 vol%) emulsions, in which an excellent anti-agglomerant (AA) cocamidopropyl dimethylamine (CDA) was employed in combination with sorbitan monododecanoate (Span 20). The CH4 storage achieved 151.1 v/vh (volume ratio of gas to hydrate, the theoretical value is 172 v/vh) in the 60 vol% systems within 60 min, which was significantly increased than the hydrate formation tests in the presence of single (Span 20, CDA) and combined additives (Span 20 coupled with tetrabutylammonium bromide (TBAB), fatty alcohol polyoxyethylene ether, N = 3 (AEO-3), l-tryptophan (L-Trp), sodium dodecyl sulfate (SDS), respectively). The effect of CDA concentration, initial pressure and stirring speed on hydrate formation was investigated. The fastest hydrate growth lasted 20 min for the test with 1000 rpm and the CH4 storage attained 151.9 v/vh. The maximum gas uptake achieved 166.2 v/vh within 2 h for the test with 8.2 MPa. No foams were observed in hydrate dissociation and the tests can be repeatable.

DEVELOPMENT AND VALIDATION OF HPLC-METHOD DETERMINING QUANTITATIVE CONTENT OF CEFTIOFUR HYDROCHLORIDE IN SUSPENSIONS FOR INJECTION

Ceftiofur is a third-generation cephalosporin used in veterinary medicine to treat infections caused by gram-negative and gram-positive bacteria. It is most often used in the form of suspensions for injections based on a lipid matrix, since the active substance is poorly soluble in water. The analysis of such a drug by direct spectrophotometry is difficult due to the components of the matrix, therefore it is proposed to develop a high-performance liquid chromatography method with UV detection.&#x0D; The aim of the work was to develop a method of identification and quantitative determination of ceftiofur hydrochloride in suspensions for injections. The method was developed and validated according to the indicators of selectivity, robustness, linearity and suitability parameters of the chromatographic system. Suspension for injections containing ceftiofur 50 mg/ml was used as a sample-object for method development. The standard sample and the test sample were dissolved in the mobile phase to a concentration of 50 μg/ml. The total uncertainty of the analysis was 1.62%, which is within the limits recommended in DFU 2.0. The samples were separated on a Dionex Ultimate 3000 chromatograph equipped with a Kinetex C18-XB 150×4.6, 5 μm chromatographic column. The mobile phase was a mixture of acetonitrile and 0.05 M ammonium acetate, 0.01 M tetrabutylammonium bromide with a pH of 6.8, titrated with acetic acid, in a volume ratio of 3:7. Ceftiofur hydrochloride was detected spectrophotometrically at a wavelength of 290 nm.&#x0D; Under the above conditions, it was possible to completely separate ceftiofur (retention time of the chromatographic peak – 4.4 min) and other components of the studied drug. At the same time, the suitability parameters of the chromatographic system did not exceed the limits specified in the recommendations of the USA Food and Drug Association. For the ceftiofur hydrochloride peak, the efficiency of the chromatographic system was 13,900 theoretical plates. The relative standard deviation (RSD) for the peak areas of the active substance was ±0.11 %, and the peak separation coefficient (RS) of ceftiofur hydrochloride from other components of the drug was 17.3. The symmetry coefficient of the peak was 1.02. The calibration curves were linear in the recommended DFU 2.0 range (80–120% of the nominal concentration of the corresponding active substance). The coefficient of linearity (R2) for the peak area of ceftiofur hydrochloride was 0.9992.

K2CO3/TBAB, a Composite of Inorganic and Organic Salts, a Novel and Powerful Media for Regioselective Michael Addition of Dihydropyrimidinones to Acrylic Esters Under and Without Solvent Conditions

Aims: Synthesis of dihydropyrimidinones derivatives. Background: carrying out reactions in the green route and organic solvent-free conditions. Objective: Regioselective Michael addition of dihydropyrimidinones to acrylic esters. Methods: The reaction proceeded in the presence of K2CO3/TBAB, a media of inorganic base K2CO3 and organic ionic salt TBAB (tetrabutylammonium bromide) at 100oC. Results: A series of new dihydropyrimidinone derivatives using aza-Michael addition reaction were synthesized under solvent-free conditions. Conclusion: The reaction is characterized by high efficiency, relatively short reaction time, high yields, simple environmentally friendly reaction conditions. Other: The reaction of acrylic esters with dihydropyrimidinones produced N3-substituted derivative of dihydropyrimidinones with 85-95% yields in 6 h.

Creation of Highly Dispersed Supported Polyoxometalate Cesium Salts via Cation Exchange from Alkylammonium Salts on Supports

AbstractWe have reported several precisely designed metal‐oxo clusters on lacunary polyoxometalate (POM) tetra‐n‐butylammonium (TBA) salts in organic solvents. However, owing to their low thermostability and/or low effective surface area, POM TBA salts are not amenable to heterogeneous catalysts for gas‐phase reactions at high temperature. To avoid this problem, we developed a new preparation method that obtains highly dispersed supported‐POM Cs salts (Cs−POM/support) via cation exchange from the corresponding TBA salts on supports. In this study, a model Keggin‐type POM called TBA4PVMo11O40 (TBA−PVMo11) is supported on oxides (TBA−PVMo11/support) using an incipient wetness method in acetonitrile. This TBA−PVMo11/support was cation‐exchanged with cesium trifluoromethanesulfonate in ethanol to obtain supported‐POM Cs salts (Cs−PVMo11/support). Various characterizations revealed that the TBA−PVMo11/support maintained the original Keggin structure during cation exchange and that Cs−PVMo11 was highly dispersed on the supports. Furthermore, Cs−PVMo11/support maintained the Keggin structure even after calcination at 573 K under an aerobic condition.

Novel and Highly Sensitive Electrochemical Sensor for the Determination of Oxytetracycline Based on Fluorine-Doped Activated Carbon and Hydrophobic Deep Eutectic Solvents.

Residues of oxytetracycline (OTC), a veterinary antibiotic and growth promoter, can be present in animal-derived foods; their consumption is harmful to human health and their presence must therefore be detected and regulated. However, the maximum residue limit is low, and consequently highly sensitive and accurate detectors are required to detect the residues. In this study, a novel highly sensitive electrochemical sensor for the detection of OTC was developed using a screen-printed electrode modified with fluorine-doped activated carbon (F-AC/SPE) combined with a novel deep eutectic solvent (DES). The modification of activated carbon by doping with fluorine atoms (F-AC) enhanced the adsorption and electrical activity of the activated carbon. The novel hydrophobic DES was prepared from tetrabutylammonium bromide (TBABr) and a fatty acid (malonic acid) using a green synthesis method. The addition of the DES increased the electrochemical response of F-AC for OTC detection; furthermore, it induced preconcentration of OTC, which increased its detectability. The electrostatic interactions between DES and OTC as well as the adsorption of OTC on the surface of the modified electrode through H-bonding and π-π interactions helped in OTC detection, which was quantified based on the decrease in the anodic peak potential (E pa = 0.3 V) of AC. The electrochemical behavior of the modified electrode was investigated by cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy. Under optimum conditions, the calibration plot of OTC exhibited a linear response in the range 5-1500 μg L-1, with a detection limit of 1.74 μg L-1. The fabricated electrochemical sensor was successfully applied to determine the OTC in shrimp pond and shrimp samples with recoveries of 83.8-100.5% and 93.3-104.5%, respectively. In addition to the high sensitivity of OTC detection, the proposed electrochemical sensor is simple, cost-effective, and environmentally friendly.

Diclofenac Sodium Solvent Extraction Based on Two‐Phase Flow Patterns

AbstractDiclofenac (DF) solvent extraction using tetra‐n‐butyl ammonium bromide (TBAB) in Y‐type microfluidic junctions with liquid‐liquid two‐phase flow patterns was investigated. The hydrodynamics of parallel, slug, and droplet flows were examined. The results indicated that the extraction efficiency decreased with increasing velocity. At QO/QA greater than 2.5, the flow pattern was converted from slug into droplet flow, and due to the enlargement of the specific surface area, the extraction efficiency increased. Slug flow provided an equilibrium extraction efficiency of 99.2 %. The overall volumetric mass transfer coefficient at different lengths and widths was evaluated. The best mass transfer performance occurred in microchannels with a length of 9 cm and a width of 400 µm.

Semi-clathrate hydrate slurry as a cold energy storage and transport medium: Rheological study, energy analysis and enhancement by amino acid

Tetra-n-butylammonium bromide (TBAB) semi-clathrate hydrate is an attractive phase change material for cold energy storage and transport. The high viscosity of hydrate slurry is a major challenge for process design and causes large pumping power consumption, not to mention the significant discrepancy of viscosity data observed in the literature. In this study, the discrepancy was clarified by studying the rheology of TBAB semi-clathrate hydrate slurry (SHS) using a rheometer with seed-induced in-situ formation of hydrate up to a high hydrate fraction (∼0.51). TBAB SHS exhibited a non-Newtonian shear-thinning behavior. Its apparent viscosity increased exponentially with the increase of hydrate fraction. Type B TBAB SHS was recommended due to its lower apparent viscosity than type A TBAB SHS. Energy analysis revealed that TBAB SHS with appropriate hydrate fractions could outperform chilled water to provide the same cooling capacity but consume less pumping power. Furthermore, to reduce the viscosity, an environmentally benign additive l-tryptophan was identified and employed for the first time. Addition of l-tryptophan up to 1.0 wt% in TBAB SHS significantly decreased the apparent viscosity and lead to a 68.7% reduction of pumping power consumption compared with chilled water. This work demonstrated the potential of TBAB SHS as a more efficient next-generation secondary refrigerant and the addition of a small dosage of l-tryptophan would considerably enhance its economic strength in cooling applications.

Deep Eutectic Solvents for the Separation of Toluene/1-Hexene via Liquid–Liquid Extraction

The separation of aromatic/olefin mixtures is a difficult task in the petrochemical industry, since the boiling points of these hydrocarbons are very similar. This work aims to use deep eutectic solvents (DESs) for the extraction of toluene from 1-hexene by liquid–liquid extraction. A total of 53 DESs were studied qualitatively and quantitatively using the COSMO-RS approach to separate the binary mixture of toluene and 1-hexene. The selectivity, capacity, and performance index of all DESs were evaluated by calculating the activity coefficient at infinite dilution. The σ-profile and σ-potential of each component were interpreted to evaluate the interactions between the different species. We then selected three DESs for experimental validation, namely benzyltriphenylphosphonium chloride:triethylene glycol BzTPPCl:TEG (1:8), tetrabutylammonium bromide:triethylene glycol TBABr:TEG (1:3), and tetrabutylammonium bromide:ethylene glycol TBABr: EG (1:4). Experimental liquid–liquid equilibrium data were obtained for the ternary mixtures {1-hexene (1) + toluene (2) + DES (3)} at T = 298.15 K and atmospheric pressure. Based on the selectivity data and the solute distribution ratio, the feasibility of different DESs as extractive solvents was tested. Finally, 1H NMR was performed to elucidate the extraction mechanism. No DES was found in the raffinate phase, indicating minimal cross-contamination.

Nickel-Catalyzed Cyanation of (Hetero)aryl Bromides Using DABAL-Me3 as a Soluble Reductant.

A nickel-catalyzed cyanation of (hetero)aryl halides using air-stable bis(trimethylaluminum)-1,4-diazabicyclo[2.2.2]octane (DABAL-Me3) as a soluble reductant has been developed. The reaction uses readily available and inexpensive Ni(dppf)Cl2 as a precatalyst, a substoichiometric amount of Zn(CN)2, and DABAL-Me3 as an alternative to commonly prescribed insoluble reductants. We found the addition of catalytic tetrabutylammonium bromide (TBABr) to be beneficial, due to facilitating dissolution of low levels of the cyanide salt (confirmed via a control study). Similarly, slow addition of a tetrabutylammonium cyanide (TBACN) solution is effective and results in a completely homogeneous reaction mixture.

Green Synthesis of Acylhydrazides Involving a Heterocyclic Moiety using Terminal Dihaloalkanes in Organic Salt Media under Solvent-Free Conditions

Abstract: This paper aimed at investigating the reaction of some acyl hydrazides with different terminal dibromoalkanes. This investigation revealed that acyl hydrazide by reacting with 1,4 and 1,5- dibromoalkanes in the presence of DABCO (1,4-diazabicyclo[2.2.2]octane) and TBAB (tetrabutylammonium bromide) underwent a facile intramolecular N2-double-alkylation to form pyrrolidine and piperidine ring derivatives under solvent-free conditions. Moreover, the alkylation of acyl hydrazide with 1,6-dibromohexane as a substrate produced the related N2-mono-alkylated derivatives under the same conditions. Interestingly, using K2CO3 as the base in this reaction for 1,6-dibromohexane led to acyl hydrazide containing an azepane ring. Surprisingly, direct alkylation of 4-nitrobenzohydrazide with 1,2-dibromoethane led to an oxadiazine ring derivative. The product yield was found to be 60- 85% in 6-12 h.

Novel Antireflection Coatings Obtained by Low-Temperature Annealing in the Presence of Tetrabutylammonium Bromide and Gold Nanoparticles.

In this work, nanoporous antireflective coatings on silicate glass were obtained from silicon dioxide sol compositions by the sol-gel method in the presence of quaternary ammonium salt (tetrabutylammonium bromide) at different annealing temperatures (200-250 °C). Varying the salt concentration from 3 to 5 wt.%, we achieved the transmittance of the coatings of about 97% at 250 °C in comparison with 91% for clean glass in the wavelength range from 400 to 1100 nm. The addition of gold nanoparticles to the composition containing 5 wt.% tetrabutylammonium bromide allowed us to decrease the annealing temperature to 200 °C, preserving the transmittance at the level of 96.5%. For this case, the optimal concentration of gold nanoparticles is determined (2.6 × 10-9 mol/mL). According to the SEM analysis, the obtained antireflective coatings contain pores with a minimum area size up to 4 nm2.

Phase behavior and molecular insights on the separation of dimethyl carbonate and methanol azeotrope by extractive distillation using deep eutectic solvents

Deep eutectic solvents (DESs) exhibit good separation performance as extractants in extractive distillation. In this study, choline chloride (ChCl)-based and tetrabutylammonium bromide (TBAB)-based DESs were prepared using ChCl and TBAB as hydrogen bond acceptors (HBAs) and urea, glycerol (G), malonic acid (MA), and levulinic acid (LA) as hydrogen bond donors (HBDs). Based on the COSMO-SAC model, the possibility of separating the binary azeotropes of methanol (MeOH) and dimethyl carbonate (DMC) using five DESs was verified. The binary azeotropes of MeOH and DMC were separated by extractive distillation using five DESs, and their separation performance was investigated. The experimental results revealed that ChCl-urea had the best separation effect on the binary azeotropes MeOH and DMC. The macroscopic separation phenomenon and microscopic molecular mechanisms were studied systematically. The interaction of the DESs with MeOH and DMC was investigated at the molecular level by quantum chemical (QC) calculations, and the important role of the hydrogen bond of the DESs in extractive distillation was revealed. The experimental and QC results demonstrate that DESs have a significant effect on the intermolecular forces and can effectively separate azeotropes.

Molecular dynamics simulations of interfacial structure, dynamics, and interfacial tension of tetrabutylammonium bromide aqueous solution in the presence of methane and carbon dioxide.

The interfacial behavior of tetrabutylammonium bromide (TBAB) aqueous solutions in the absence of gas and the presence of methane and carbon dioxide gases is studied by molecular dynamics simulations. The aqueous TBAB phase, at concentrations similar to the solid semiclathrate hydrate (1:38 molratio), has a smaller interfacial tension and an increase in the gas molecules adsorbed at the interface compared to that in pure water. Both these factors may contribute to facilitating the uptake of the gases into the solid phase during the process of semiclathrate hydrate formation. At similar gas pressures, CO2 is adsorbed preferentially compared to CH4, giving it a higher surface density, due to the stronger intermolecular interactions of CO2 molecules of the solution at the interface. The increase in relative adsorption of CH4 at the solution surface compared to that in pure water surface is due to the hydrophobic interactions between the n-alkyl chains of the TBA+ cation and methane gas.

High-pressure CO2 solubility measurement in aqueous mixtures of (2-amino-2-methyl-1-propanol (AMP) and deep eutectic solvent (tetra butyl ammonium bromide 1: 3 ethylene glycol)) at various temperatures

In this work, we measured the CO2 solubility in a mixture of aqueous 2-amino-2-methyl-1-propanol (AMP) and deep eutectic solvent (DES) made by tetra butyl ammonium bromide (TBAB) and ethylene glycol (EG) statically at high-pressure. Measurements were performed isothermally at 313.15, 328.15, and 343.15 K and in the pressure range of 100–5100 kPa. The solvent compositions used for the DES (TBAB 1: 3 EG) + AMP + H2O systems were (7.5–30–62.5) (15–30–55) (22.5–30–47.5) and (30–30–40) wt.%. The solubility results showed that decreasing temperature and increasing pressure enhanced the solubility of CO2 in the solvent mixtures. Also, increasing the mass concentration of deep eutectic solvent in the system at a constant temperature reduces the gas's solubility. Besides, in this study, a correlation of gas partial pressure against CO2 loading and temperature was obtained to calculate the gas solubility in the studied system, which agrees with the experiment. Finally, the heat absorption enthalpy of CO2 was calculated using the Clausius-Clapeyron equation. The enthalpy of dissolution changed with a smoother slope as the mass percentage of DES increased.

Separation of ethyl acetate-isopropanol using low transition temperature mixtures: Vapor-liquid equilibrium experiments and quantum chemical calculation

Ethyl acetate and isopropanol, as essential chemical ingredients and organic solvents, play an important role in the industry. At atmospheric pressure, ethyl acetate and isopropanol form an azeotrope, which can be separated by extractive distillation. The choice of extractant is critical in extractive distillation. Low transition temperature mixtures (LTTMs), which are emerging as efficient green solvents, are used as extractants in this work. The effect of type and structure on separation performance were studied, and three LTTMs were selected for the separation of the ethyl acetate-isopropanol system. The vapor–liquid equilibrium (VLE) data of ethyl acetate-isopropanol-LTTMs was measured by experiments, and the results showed that when the mole fraction of LTTMs was 0.1, all three LTTMs could break the azeotrope of ethyl acetate and isopropanol, especially LTTM1 (tetrabutylammonium bromide: ethanolamine = 1:2) having the best selectivity. To acquire the binary interaction parameters, the NRTL model was used to fit the experimental data, and the regression data was in good agreement with the experimental data. In addition, a quantum chemical method was used to investigate the interactions between molecules to gain insights into the microscopic mechanism. Results showed that the weak hydrogen bonding and van der Waals forces are formed between ethyl acetate and other systems, while moderate or weak hydrogen bonding are formed between isopropanol and other systems.

Application of levulinic acid-based natural deep eutectic solvents for extraction and determination of deltamethrin in food samples

In the study, a fast and green natural deep eutectic solvent based ultrasound-assisted liquid liquid microextraction (NDES-UALLME) were proposed for the determination and extraction of deltamethrin in food samples using UV/Vis spectrophotometry. The extraction step was based on ion-pair formation between deltamethrin and levulinic acid-tetraethylammonium bromide (as extraction solvent) at pH 5.5, and then extraction of deltamethrin into micro-drops of extraction solvent by using tetrahydrofuran. Levulinic acid-based natural deep eutectic solvents composed of natural, green compounds, i.e., choline acetyl chloride, tetrabutylammonium bromide, tetraethylammonium chloride and tetraethylammonium bromide were used for the first time as extraction solvents for extraction of deltamethrin. The NDES-UALLME procedure allowed to exclude matrixes effects and increase enrichment factor (283) of deltamethrin. Several key factors, including the type and the volume of extraction solvent, the pH of sample solution, ultrasound time, extraction temperature, ionic strength and sample volume were optimized in detail. At optimized conditions, the NDES-UALLME procedure was characterized by low limit of detection (2.4 ng mL−1), a wide linear dynamic range (8–950 ng mL−1), quantitative recoveries (93 ± 4%-103 ± 2%) and acceptable relative standard deviations (2.9%≤). The validation of NDES-UALLME procedure was carried out using recovery tests, intraday and intraday studies. The applicability of NDES-UALLME procedure was confirmed by the assay of deltamethrin in real food samples.