Combined assisted extraction techniques as green sample pre-treatments in food analysis

Seafood waste derived carbon nanomaterials for removal and detection of food safety hazards

Nanobiotechnology and the engineering of nanomaterials are currently the main focus of many researches. Seafood waste carbon nanomaterials (SWCNs) are a renewable resource with large surface area, porous structure, high reactivity, and abundant active sites. They efficiently adsorb food contaminants through π-π conjugated, ion exchange, and electrostatic interaction. Furthermore, SWCNs prepared from seafood waste are rich in N and O functional groups. They have high quantum yield (QY) and excellent fluorescence properties, making them promising materials for the removal and detection of pollutants. It provides an opportunity by which solutions to the long-term challenges of the food industry in assessing food safety, maintaining food quality, detecting contaminants and pretreating samples can be found. In addition, carbon nanomaterials can be used as adsorbents to reduce environmental pollutants and prevent food safety problems from the source. In this paper, the types of SWCNs are reviewed; the synthesis, properties and applications of SWCNs are reviewed and the raw material selection, preparation methods, reaction conditions and formation mechanisms of biomass-based carbon materials are studied in depth. Finally, the advantages of seafood waste carbon and its composite materials in pollutant removal and detection were discussed, and existing problems were pointed out, which provided ideas for the future development and research directions of this interesting and versatile material. Based on the concept of waste pricing and a recycling economy, the aim of this paper is to outline current trends and the future potential to transform residues from the seafood waste sector into valuable biological (nano) materials, and to apply them to food safety.

Simple and rapid ionic liquid-based one-, two-, three-phase transition microextraction for efficient extraction of trace organic pollutants and elimination of lipid co-extractives from fatty food matrices

Extraction of trace contaminants from fatty food matrices is challenging in food analysis. Herein, a new ionic liquid-based one-, two-, three-phase transition microextraction (IL-OTTPTME) was proposed to efficiently extract trace targets while simultaneously eliminating lipid co-extractives. The method performance was illustrated through the determination of chrysoidine in fatty soybean products using high-performance liquid chromatography-ultraviolet/visible detection. The strong interactions and infinite contact between IL and chrysoidine in the one-phase system ensured ultra-high extraction efficiency (∼100 %). Density functional theoretical calculations confirmed the presence of strong hydrogen bonding and π-π interactions. The formation of the three-phase system during extraction could completely eliminate lipid co-extractives. The IL-OTTPTME integrated extraction, enrichment and cleanup steps into one step, making it rapid and extremely easy to operate. The method had a wide linear range of 0.5-5000 μg/kg and low limit of detection (0.15 μg/kg). It also had satisfactory relative recoveries (95.1 %-104.0 %) and low RSDs (≤5.0 %, n = 5).

Microwave-Assisted Dispersive Liquid-Liquid Microextraction Combined with HPLC for the Determination of Three Biogenic Amines in Beverages

Microwave-assisted dispersive liquid-liquid microextraction (MADLLME) coupled with high-performance liquid chromatography (HPLC) with diode array detector was used for the extraction and determination of three biogenic amines (BAs), including tryptamine, histamine and phenylethylamine in beverages (beer, cherry juice and white spirit). Compared with solid-phase extraction, solid-phase microextraction and liquid-phase microextraction, which is more solvent use with lower extraction efficiency, this MADLLME method obviously shortened analytical time, the rapid heating of aqueous samples with non-ionizing electromagnetic radiation, a lower solvent use and enhanced extraction efficiency. Because of good extraction for three BAs, [3C6PC14][FeCl4] was used as an extraction solvent. We showed a tunable selectivity of magnetic ionic liquids (MILs) toward extracting BAs by changing anion or cation due to the modification of the interaction between the MIL and the BAs. Extraction conditions including the type and volume of extraction solvent, microwave power, microwave-assisted extraction time, sample pH, disperser and interference experiment were investigated. Under the optimal conditions, a good linear relationship was found in the concentration range of 100-2,000 ng mL-1 for three BAs with correlation coefficient (R2) of 0.995-0.999. The limit of detections (S/N = 3) and limit of quantitations (S/N = 10) were in the range of 3.46-4.96 ng mL-1 and 10.44-14.88 ng mL-1, respectively. The recoveries of three targets were in the range of 84.3-108.5%, and the relative standard deviations based on the peak areas for six replicate analyses of beverages spiked with 10, 50 and 100 ng mL-1 of each biogenic amine were lower than 7.9%. This method has also been successfully applied to analyze the real samples at three different spiked concentrations, and excellent results have been obtained.

Ethanol-ammonium sulfate system based modified quick, easy, cheap, effective, rugged and safe method for the determination of four neonicotinoid pesticide and metabolite residues in two canned fruits

As the pesticide and its metabolite residues in processed fruits could become a significant route of human exposure. The work presented herein focuses on developing a feasible quick, easy, cheap, effective, rugged and safe method with improved extraction and cleanup system for the determination of imidacloprid, acetamiprid, thiamethoxam and clothianidin (metabolite of thiamethoxam) in canned fruits. The low toxic solvent ethanol was used to extract the analytes, and ammonium sulfate was used to promote the phase separation. Moreover, the carboxylated multi walled carbon nanotube was acted as the clean-up sorbent for removal of high solubility impurities. The proposed method was validated with fortified real samples at different concentration levels (20∼200 μg kg^-1 ). Recoveries obtained from three spiked levels (20, 50, 200 μg kg^-1 ) were ranged from 74.9% to 86.4% with relative standard deviations of the intra-day and inter-day in the range of 0.8 to 5.5% and 2.0 to 7.1%, respectively. Limit of detections were ranged from 0.2 to 0.5 μg kg^-1 and 0.2 to 0.6 μg kg^-1 for orange and peach, respectively. The results demonstrated that the proposed method could be considered appropriate, comparatively lower toxic for the analysis of neonicotinoid pesticide residues in canned fruit. This article is protected by copyright. All rights reserved.

Ultrasound-assisted micellar cleanup coupled with large-volume-injection enrichment for the analysis of polar drugs in blood and zebrafish samples

A novel ultrasound-assisted micellar cleanup strategy (UAMC) coupled with large volume injection (LVI) high performance liquid chromatography (HPLC) method was proposed and successfully applied to the analysis of cefathiamidine in complex biological samples such as whole blood, plasma, serum and even zebrafish, a challenging positive real sample. Based on the micelle-biomacromolecule interaction, the phase-separation feature of surfactant micelles and ultrasound cavitation, UAMC possessed an impressive matrix cleanup capability and could rapidly reach distribution equilibrium (approximately 2 min), which enabled simultaneous sample cleanup and analyte extraction within 8 min. Due to the high cleanup efficiency of UAMC, large volume of pretreated samples could be injected for analysis without peak broadening, impurity interference and column degradation. Thus, online analyte enrichment could be automatically performed to significantly improve method sensitivity by the column-switching LVI-HPLC system, a commercial HPLC system with small modifications. The UAMC-LVI-HPLC method creatively integrated sample cleanup, analyte extraction and on-column enrichment into simple operation. In addition, the UAMC-LVI-HPLC method enabled non-matrix-matched analysis of cefathiamidine in complex biological samples. This feature was helpful to address the problems caused by conventional matrix-matched or internal standard calibration methods, such as matrix bias, increased workload, limited availability of suitable blank matrices and the use of expensive internal standards. The method had low limits of detections (e.g., 0.0051 mg/L and 0.038 μg/g), wide linear ranges (0.030-100 mg/L and 0.15-489 μg/g), good linear correlation (R² = 0.9999), satisfactory accuracy (97.6-109.7%) and excellent intra- and interday precision (0.5-4.9%). Thus, UAMC-LVI-HPLC is expected to be a promising candidate for bioanalysis in therapeutic drug monitoring or pharmacokinetic and toxicology studies in the future.

Current overview and perspectives in environmentally friendly microextractions of carbamates and dithiocarbamates

Carbamates and dithiocarbamates are two classes of pesticides widely employed in the agriculture practice to control and avoid pests and weeds, hence, the monitoring of the residue of those pesticides in different foodstuff samples is important. Thus, this review presents the classification, chemical structure, use, and toxicology of them. Moreover, it was shown the evolution of liquid- and solid-phase microextractions employed in the extraction of carbamates and dithiocarbamates in water and foodstuff samples. The classification, operation mode, and application of the microextractions of liquid-phase and solid-phase used in their extraction were discussed and related to the analytical parameters and guidelines of green analytical chemistry.

Molecularly Imprinted Polymers for Dispersive (Micro)Solid Phase Extraction: A Review

The review describes the development of batch solid phase extraction procedures based on dispersive (micro)solid phase extraction with molecularly imprinted polymers (MIPs) and magnetic MIPs (MMIPs). Advantages and disadvantages of the various MIPs for dispersive solid phase extraction and dispersive (micro)solid phase extraction are discussed. In addition, an effort has also been made to condense the information regarding MMIPs since there are a great variety of supports (magnetite and magnetite composites with carbon nanotubes, graphene oxide, or organic metal framework) and magnetite surface functionalization mechanisms for enhancing MIP synthesis, including reversible addition-fragmentation chain-transfer (RAFT) polymerization. Finally, drawbacks and future prospects for improving molecularly imprinted (micro)solid phase extraction (MIMSPE) are also appraised.

Magnetic Micro-Solid-Phase Extraction Using a Novel Carbon-Based Composite Coupled with HPLC-MS/MS for Steroid Multiclass Determination in Human Plasma

A micron-sized sorbent, Magn-Humic, has been prepared by humic acids pyrolysis onto silica-coated magnetite. The material was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), thermogravimetric analysis (TGA), and Brunauer, Emmett, and Teller (BET) surface area measurements and applied for simultaneous magnetic solid-phase extraction (MSPE) of glucocorticoids, estrogens, progestogens, and androgens at ng mL⁻¹ levels from human plasma followed by high-performance liquid chromatography coupled with mass spectrometry (HPLC–MS/MS). Due to the low affinity for proteins, steroids extraction was done with no need for proteins precipitation/centrifugation. As highlighted by a design of experiments, MSPE was performed on 250 µL plasma (after 1:4 dilution) by 50 mg Magn-Humic (reusable for eight extractions) achieving quantitative recovery and satisfying clean-up. This was improved by washing (2 mL 2% v/v formic acid) prior to analytes elution by 0.5 mL 1:1 v/v methanol-acetonitrile followed by 0.5 mL methanol; eluate reduction to 0.25 mL compensated the initial sample dilution. The accuracy was assessed in certified blank fetal bovine serum and in human plasma, gaining satisfactory recovery in the range 65–122%, detection limits in the range 0.02–0.3 ng mL⁻¹ (0.8 ng mL⁻¹ for 17-β-estradiol) and suitable inter-day precision (relative standard deviation (RSD) <14%, n = 3). The method was evaluated in terms of selectivity, sensitivity, matrix-effect, instrumental carry-over, and it was applied to human plasma samples.

Microwave-Assisted Saponification Method Followed by Solid-Phase Extraction for the Characterization of Sterols and Dialkyl Ketones in Fats

Unlike other fields, the methods routinely applied for fats and oils are still tied to traditional, time- and solvent-consuming procedures, such as saponification, column chromatography and thin-layer chromatography. In this paper, microwave-assisted saponification followed by a lab-made solid-phase extraction was optimized for the characterization of either dialkyl ketones (DAK) or sterols or both simultaneously. The instrumental determination was performed by gas chromatography- flame ionization detector (GC-FID) for quantification and gas chromatography-mass spectrometry (GC-MS) for confirmation purposes. The proposed method showed good recoveries (>80%) and limit of quantification (0.04–0.07 μg/g for the 4 DAK and of 0.07 μg/g for α-cholestanol). Repeatabilities (n = 3) were below 15% for DAKs and generally lower than 6% for sterols. Accuracy on the entire sterol profile was confirmed in comparison to the International Olive Council reference method. The method was finally applied to real-world samples before and after chemical interesterification.

Molecularly Imprinted Polymer for a Smart Dispersive Micro-Solid Phase Extraction Technique for Assessing Trace Level Aflatoxins in Cultured Fish

Molecularly imprinted technology (MIT) consists of preparing materials exhibiting specific recognition cavities to selective mimic the target analytes. The prepared materials promote selective interactions with the targets and avoid interactions of concomitants from complex food, biological, clinical, and environmental matrices. This chapter provides information on a recent development of a vortex-assisted micro-solid phase extraction using a molecularly imprinted polymer (MIP) as an adsorbent for aflatoxins (AFs) determination in cultured fish. MIP particles were synthesized by precipitation polymerization using 5,7-dimethoxycoumarin as a dummy template, methacrylic acid as a functional monomer, divinylbenzene as a cross-linker, and 2,2-azobisisobutyronitrile as an initiator. Polymerization following the precipitation method guarantees homogeneous particle size distribution and the integrity of the imprinted cavities. The MIP microparticles were found to have 5 μm in diameter and a spherical shape. Important parameters such as sample extract pH, adsorption stirring speed and time, desorption stirring speed and time, elution solvent composition and volume, and polymer mass, were fully optimized. The pre-concentration method allows therefore the assessment of four major AFs (B1, B2, G1, and G2) present in cultured fish at very low levels, with pre-concentration factors from 15 to 50 depending of the volume of extract used for performing the dispersive micro-solid phase extraction (D-μ-SPE).

Hydrophobic deep eutectic solvent-based ultrasonic-assisted liquid-liquid micro-extraction combined with HPLC-FLD for diphenylamine determination in fruit

In this paper, novel high extraction efficiency hydrophobic eutectic solvents (DESs), n-octanoic acid as a hydrogen bond donor (HBD) and menthol as a hydrogen bond acceptor (HBA), were selected from five hydrophobic DESs to extract trace diphenylamine (DPA) in fruits apple, pear and orange under ultrasonic-assisted liquid-liquid micro-extraction (UA-LLME) technology before high-performance liquid chromatography (HPLC) analysis. Working parameters such as the DESs type, molar ratio, extractant volume, and ultrasonic time of the LLME hydrophobic DESs technology were optimised. Average recoveries between 96% and 108% were obtained on actual samples. This method gave lower detection limit (LOD) than other existing methods due to combining the high-efficiency extraction of hydrophobic DES and high sensitivity of fluorescence detector. This method was sensitive and eco-friendly, and can be used for the determination of trace components in fruits.

Microwave-assisted extraction followed by salting-out phase separation for hierarchical screening of illegal adulterants in aphrodisiac health products by multi-dimensional fingerprint profiling analysis

A novel method for hierarchical screening of illegal adulterants in Fur seal ginseng pills (FSGP) products was developed by microwave-assisted extraction (MAE) coupled to salting-out assisted liquid-liquid extraction (SALLE) with multi-dimensional fingerprint profiling analysis. Using a homogeneous system formed by dimethyl carbonate (DMC) and water as the extractant, the MAE conditions were investigated to maximize extraction recoveries, followed by addition of ammonium sulfate to induce DMC phase separation for SALLE enrichment of 16 potentially illegal adulterants such as phosphodiesterase type-5 inhibitors, androgens, α receptor antagonists and yohimbine etc. By means of high-performance liquid chromatography (HPLC) with diode array detection (DAD) and fluorescence detection (FLD), multi-dimensional fingerprints were acquired by multi-wavelength detection to highlight the signals of the potentially illegal adulterants and reduce or remove interferences from the sample matrix. For high accuracy and reliability, a hierarchical screening strategy was designed by multi-dimensional fingerprinting profiling analysis (MDFPA). The method exhibited proper identification and quantification performance, and it was successfully applied to screening of illegal adulterants in 18 batches of the samples through the step-by-step MDFPA. Also, the results were further confirmed by ultra high-performance liquid chromatography-quadrupole-orbitrap mass spectrometry (UHPLC-Q-Orbitrap/MS). The proposed method was proved to be a green, efficient and reliable alternative to monitoring aphrodisiac health products.

A Review on Recent Advances in the Applications of Boron-Doped Diamond Electrochemical Sensors in Food Analysis

The usage of boron-doped diamond (BDD) material has found to be very attractive in modern electroanalytical methods and received massive consideration as perspective electrochemical sensor due to its outstanding (electro)chemical properties. These generally known facilities include large potential window, low background currents, ability to withstand extreme potentials and strong tendency to resist fouling compared to conventional carbon-based electrodes. As evidence of superiority of this material, couple of reviews describing the overview of various applications of BDD electrodes in the field of analytical and material chemistry has been reported in scientific literature during last decade. However, herein proposed review predominantly focuses on the most recent developments (from 2009 to 2020) dealing with the application of BDD as an advanced and environmental-friendly sensor platform in food analysis. The main method characteristics of analysis of various organic food components with different chemical properties, including additives, flavor and aroma components, phenolic compounds, flavonoids and pesticides in food matrices are described in more details. The importance of BDD surface termination, presence of sp² content and boron doping level on electrochemical sensing is discussed. Apart from this, a special attention is paid to the evaluation of main analytical characteristics of the BDD electrochemical sensor in single- and multi-analyte detection mode in food analysis. The recent achievements in the utilizing of BDD electrodes in amperometric detection coupled to flow injection analysis, batch injection analysis, and high-performance liquid chromatography are also commented. Moreover, actual trends in sample preparation techniques prior to electrochemical sensing in food analysis are referred.

Miniaturized vortex assisted-dispersive molecularly imprinted polymer micro-solid phase extraction and HPLC-MS/MS for assessing trace aflatoxins in cultured fish

A dispersive micro-solid phase extraction approach using a molecularly imprinted polymer as an adsorbent has been developed for pre-concentrating aflatoxins from cultured fish. Aflatoxins were first isolated from fish muscle and liver by an ultrasound assisted extraction procedure using a 60 : 40 acetonitrile/0.1 M KH2PO4 aqueous buffer (pH 6.0) mixture. Polymeric adsorbent beads were synthesized using 5,7-dimethoxycoumarin as a dummy template, methacrylic acid as a functional monomer, divinylbenzene as a crosslinker, and 2,2'-azobisisobutyronitrile as an initiator. Parameters affecting the steps of extraction procedure, including the sample (fish extract) pH, adsorption stirring speed and time, desorption stirring speed and time, elution solvent ratio, and polymer capacity, were investigated and optimized. The limit of detection was found to vary from 0.29 to 0.61 μg kg-1 for the several aflatoxins. The proposed method was shown to be accurate and precise. Intraday and inter-day relative standard deviations were lower than 20%, and intraday and inter-day analytical recoveries were within the 80-100% range. The prepared adsorbent in the dispersive micro-solid phase extraction format was re-usable, and the pre-concentration procedure was found to be simple, rapid and highly selective and sensitive to identify/quantify AFs in fish.

Critical review of micro-extraction techniques used in the determination of polycyclic aromatic hydrocarbons in biological, environmental and food samples

Polycyclic Aromatic Hydrocarbons (PAHs) are ubiquitous environmental contaminants and their accurate determination is very important to human health and environment safety. In this review, sorptive-based micro-extraction techniques [such as Solid-Phase Micro-extraction (SPME), Stir Bar Sorptive Extraction (SBSE), Micro-extraction in Packed Sorbent (MEPS)] and solvent-based micro-extraction [Membrane-Mediated Liquid-Phase Micro-extraction (MM-LPME), Dispersive Liquid-Liquid Micro-extraction (DLLME), and Single Drop Micro-extraction (SDME)] developed for quantification of PAHs in environmental, biological and food samples are reviewed. Moreover, recent micro-extraction techniques that have been coupled with other sample extraction strategies are also briefly discussed. The main objectives of these micro-extraction techniques are to perform extraction, pre-concentration and clean up together as one step, and the reduction of the analysis time, cost and solvent following the green chemistry guidelines.

Microwave-Based Technique for Fast and Reliable Extraction of Organic Contaminants from Food, with a Special Focus on Hydrocarbon Contaminants

Due to food complexity and the low amount at which contaminants are usually present in food, their analytical determination can be particularly challenging. Conventional sample preparation methods making use of large solvent volumes and involving intensive sample manipulation can lead to sample contamination or losses of analytes. To overcome the disadvantages of conventional sample preparation, many researchers put their efforts toward the development of rapid and environmental-friendly methods, minimizing solvent consumption. In this context, microwave-assisted-extraction (MAE) has obtained, over the last years, increasing attention from analytical chemists and it has been successfully utilized for the extraction of various contaminants from different foods. In the first part of this review, an updated overview of the microwave-based extraction technique used for rapid and efficient extraction of organic contaminants from food is given. The principle of the technique, a description of available instrumentation, optimization of parameters affecting the extraction yield, as well as integrated techniques for further purification/enrichment prior to the analytical determination, are illustrated. In the second part of the review, the latest applications concerning the use of microwave energy for the determination of hydrocarbon contaminants-namely polycyclic aromatic hydrocarbons (PAHs) and mineral oil hydrocarbons (MOH)-are reported and critically overviewed and future trends are delineated.