Determination of pesticide residues in soybeans using QuEChERS followed by deep eutectic solvent-based DLLME preconcentration prior to gas chromatography-mass spectrometry analysis.

A reliable and greener alternative to the usual extraction methods is reported for the determination of pesticide residues in soybeans. This novel approach combines the classical QuEChERS extraction method with a DLLME (dispersive liquid-liquid microextraction) step, utilizing a deep eutectic solvent (DES) - camphor: hexanoic acid (1:1 molar ratio) - as the microextraction solvent. This DES has never been employed in pesticide analysis by gas chromatography-mass spectrometry of complex matrices like soybeans.

Bisphenol A and its structural analogues in infant formulas available in the Brazilian market: Optimisation of a UPLC-MS/MS method, occurrence, and dietary exposure assessment.

For the first time, structural analogues to bisphenol A were investigated in infant formulas marketed in Brazil. A fast and high throughput UPLC-MS/MS method was established for simultaneous analysis of bisphenol A, B, E, F, and S in complex infant formula matrices. The influence of mobile phase composition on electrospray ionization response in negative mode was studied to improve the detectability of the method.

Occurrence and risk assessment of endocrine-disrupting compounds in fish muscle: The case study of the Douro River estuary (North East Atlantic Ocean).

This work was focused on evaluating the occurrence of endocrine-disrupting compounds (EDCs) in fish muscles, such as bisphenol analogues, personal care products, including some UV-filters and musk fragrances, and selected pesticides. A total of 238 muscle samples of three fish species (Platichthys flesus, Mugil cephalus, and Dicentrarchus labrax) of an important estuary ending in the North East Atlantic Ocean (Douro River estuary, Portugal), in different seasons of the year, was analysed. M.

Multi-analyte gas chromatography-mass spectrometry method to monitor bisphenols, musk fragrances, ultraviolet filters, and pesticide residues in seafood.

A gas chromatography-mass spectrometry method for the analysis of thirty-six anthropogenic contaminants in the edible portion of four distinct seafood items is reported. Considering the heterogeneous composition of algae, mussels, and lean/fatty fish muscles, a generic sample preparation based on the QuEChERS procedure combined with dispersive liquid-liquid microextraction (DLLME) with in situ acetylation was successfully applied for quantification of pesticide residues, bisphenols, musk fragrances and UV-filters. Matrix effects were influenced by the type of seafood, with the lowest effects being observed with EMR-lipid and graphitized carbon black sorbents in dispersive solid-phase extraction cleanup step.

Exploring miniaturized sample preparation approaches combined with LC-QToF-MS for the analysis of sulfonamide antibiotic residues in meat- and/or egg-based baby foods.

Miniaturized and simplified sample preparation methods with reduced consumption of chemicals and non-halogenated solvents are presented for the determination of 12 sulfonamides in baby foods. Hydrophilic interaction liquid chromatography coupled to quadrupole time-of-flight mass spectrometry was used for the identification and quantification of the compounds based on the acquisition of full spectrum at high resolution with accurate mass for precursor and its fragment ions. Three miniaturized protocols based on QuEChERS, salting-out assisted liquid-liquid extraction or low-temperature cleanup were evaluated regarding the extraction efficiency and removal capability of matrix co-extractives.

Acrylamide in non-centrifugal sugar from Latin American markets: in-house validation of an LC-MS/MS method, dietary exposure assessment and risk characterisation in Brazil and Colombia.

A liquid chromatography tandem mass spectrometry method (LC-MS/MS) preceded by a rapid and simple QuEChERS-based sample preparation was developed and validated for the determination of acrylamide in non-centrifugal sugar (NCS), a solid product obtained from sugarcane juice without centrifugation, up to a concentration greater than 90 ºBrix. Adequate linearity in calibration curves, analytical selectivity and sensitivity were achieved. A limit of detection (LOD) and a limit of quantitation (LOQ) of 10 and 20 µg kg, respectively, were obtained.

Hydrophilic interaction liquid chromatography coupled to quadrupole time-of-flight mass spectrometry as a potential combination for the determination of sulfonamide residues in complex infant formula matrices.

An accurate, sensitive and selective analytical method is proposed for sulfonamide residues analysis in infant formulas based on hydrophilic interaction liquid chromatography (HILIC) and quadrupole time-of-flight mass spectrometry in full scan mode. The sample preparation approach involves low-temperature lipid precipitation followed by dispersive solid-phase extraction with PSA and C sorbents, which was successfully optimized using Plackett-Burman design. In order to achieve high analytical sensitivity, the influence of HILIC conditions on sulfonamide ionization was investigated, such as the mobile phase composition, buffer concentration, and sample diluent for injection.

Multivariate optimization of extraction and validation of phenolic acids in edible mushrooms by capillary electrophoresis.

A "green" analytical method is reported for the determination of phenolic acids in mushrooms. The sample preparation involves aqueous extraction based on acid hydrolysis, followed by analysis of extracts by capillary electrophoresis with diode array detector (CE-DAD). A central composite design was used to obtain the optimum conditions for the extraction of compounds from mushrooms, including the concentration of hydrochloric acid (2 mol·L), temperature (80 °C) and time (30 min).

Gas chromatography-mass spectrometry determination of polycyclic aromatic hydrocarbons in baby food using QuEChERS combined with low-density solvent dispersive liquid-liquid microextraction.

A sensitive GC-MS method is reported for the determination of twelve polycyclic aromatic hydrocarbons (PAHs) in baby food. The sample preparation involves QuEChERS extraction combined with low-density solvent dispersive liquid-liquid microextraction (LDS-DLLME) and ultra-low temperature (-80 °C). Plackett-Burman screening design was employed to identify the main sample preparation variables that affect the extraction efficiency, such as the volume of toluene used in LDS-DLLME.

Simultaneous determination of acrylamide and 4-hydroxy-2,5-dimethyl-3(2H)-furanone in baby food by liquid chromatography-tandem mass spectrometry.

A liquid chromatography triple quadrupole mass spectrometry method was developed and validated for the simultaneous determination of acrylamide and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF) in baby food. The sample preparation involves acetonitrile-based extraction combined with dispersive primary secondary amine (PSA) cleanup and cation-exchange solid-phase extraction (SPE), which promotes efficient removal of matrix interferences. Analytical selectivity and sensitivity were achieved for the quantification of acrylamide and HDMF in complex matrices such as fruit, cereal and milk-based baby foods; furthermore, adequate linearity (range 10-300μgkg) in solvent and matrix-matched calibration curves, and appropriate recoveries (94-110%) and precision (RSD≤10%), under repeatability and within-laboratory reproducibility conditions, were also obtained.

Comparison of green sample preparation techniques in the analysis of pyrethrins and pyrethroids in baby food by liquid chromatography-tandem mass spectrometry.

A new selective and sensitive liquid chromatography triple quadrupole mass spectrometry method was developed for simultaneous analysis of natural pyrethrins and synthetic pyrethroids residues in baby food. In this study, two sample preparation methods based on ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) and salting-out assisted liquid-liquid extraction (SALLE) were optimized, and then, compared regarding the performance criteria. Appropriate linearity in solvent and matrix-based calibrations, and suitable recoveries (75-120%) and precision (RSD values≤16%) were achieved for selected analytes by any of the sample preparation procedures.

Multiclass pesticide analysis in fruit-based baby food: A comparative study of sample preparation techniques previous to gas chromatography-mass spectrometry.

With the aim to develop a new gas chromatography-mass spectrometry method to analyze 24 pesticide residues in baby foods at the level imposed by established regulation two simple, rapid and environmental-friendly sample preparation techniques based on QuEChERS (quick, easy, cheap, effective, robust and safe) were compared - QuEChERS with dispersive liquid-liquid microextraction (DLLME) and QuEChERS with dispersive solid-phase extraction (d-SPE). Both sample preparation techniques achieved suitable performance criteria, including selectivity, linearity, acceptable recovery (70-120%) and precision (⩽20%). A higher enrichment factor was observed for DLLME and consequently better limits of detection and quantification were obtained.

Optimisation of a sample preparation method for the determination of fumonisin B(1) in rice.

A simple, rapid and cost-effective sample preparation method for the determination of fumonisin B1 in rice was optimised using a strategy of sequential experimental designs. Initially, a Plackett-Burman design was applied to select the statistically significant variables for the determination of fumonisin B1, and then, a central composite rotatable design was used to define the optimal conditions of these variables. The method involves extraction with a 50% acetonitrile aqueous solution and glacial acetic acid, liquid-liquid partitioning with addition of anhydrous sodium sulphate and sodium chloride, followed by dispersive SPE clean-up with diatomaceous earth.