Crown ether microfunctionalized carbon nanotubes for dispersive micro-solid-phase extraction of sudan dyes and their metabolites

Ultrasound-assisted dispersive micro solid phase extraction of maneb in water and food samples with new hybrid block copolymer material prior to micro-spectrophotometric analysis

A simple and effective ultrasound-assisted dispersive micro solid-phase extraction (UA-dμSPE) method was developed for the spectrophotometric determination of traces maneb in food and water. In this study, a new hybrid block copolymer poly (vinyl benzyl chloride-b-dimethyl aminoethyl methacrylate) (Pvb-DMA) was synthesized and characterized using techniques such as FTIR, SEM-EDX. The synthesized Pvb-DMA was used as an adsorbent for the extraction of maneb for first time in this study. The effects of different experimental variables such as pH, adsorbent amount, sample volume, eluent type were optimized. The statistical toll factorial design was applied to estimate the individual and combined impact of parameters on the extraction of maneb. The applicability of different solvents such as acetone, methanol, ethanol, tetrahydrofuran, acetonitrile for maneb recovery from adsorbent was tested. The detection and quantification limits were found to be 3.3 ng mL-1 and 10.0 ng mL-1, respectively. In addition, the preconcentration factor and linear range was obtained 300 and 10-500 ng mL-1. The extraction recovery and relative standard deviation were found to be 95 % and 2.8 %, respectively.

Synthesis of Functionalized Pyridine Modified Magnetic Nanoparticles for Utilization in Magnetic Solid-Phase Extraction of Tebuconazole and Propiconazole Followed by Quantification via High-Performance Liquid Chromatography-Ultraviolet Detection

In the current study, a new magnetic sorbent (Fe3O4@2,6-diamino-4-(3,4-dihydroxyphenyl) pyridine-3,5-dicarbonitrile) was prepared as a new and efficient sorbent to be used in the magnetic solid-phase extraction method to extract tebuconazole and propiconazole as model compounds. In this regard, effective parameters such as pH of the sample solution, desorption volume, ionic strength, extraction time, desorption time, and amount of the magnetic sorbent were optimized using experimental design. In the optimal condition, the linear dynamic ranges for tebuconazole and propiconazole were between 0.5 and 200.0 µg/L. Also, the limits of detection, limits of quantification, and relative standard deviations were 0.21-0.14 µg/L, 0.49-0.45 µg/L, and 1.3%-4.6%, respectively. The estimated enrichment factors for tebuconazole and propiconazole were 22 and 28, respectively. The absolute recovery (AR%) values for tebuconazole and propiconazole were also 67% and 84%, respectively. Finally, the proposed method was used for determination of tebuconazole and propiconazole in cucumber, tomato, orange, and lemon fruits. The obtained result confirmed that the presented method is capable for the analysis of the selected analytes in complicated matrices. In addition, the ARs% were in the range of 67%-84%. The result proved that the presented method can be an alternative to the extraction process of various pesticides.

Paper-supported polystyrene membranes for micro-solid phase extraction of date-rape drugs from urine: A sustainable analytical approach

BACKGROUND

The rapid development of micro-solid phase extraction (μ-SPE) procedures with new sorption materials, in particular, based on using natural materials, is currently reported. The production of these sorbents and the entire extraction procedure should support the implementation of Green Analytical Chemistry (GAC) principles. Promising materials are sorbents based on paper, which can be relatively easily modified, among others: by covering it with a polymer membrane. In this work, the practical application of paper-supported polystyrene used in the analysis of urine samples containing selected date-rape drugs (DRD) substances, and evaluation of the entire procedure using GAC metrics is presented.

RESULTS

The paper-supported polystyrene membranes were successfully fabricated and characterized. The successful polystyrene coating on the paper was confirmed through ATR-FTIR measurements, ensuring even coverage. The μ-SPE procedure using this material facilitated extraction with a throughput of approximately 120 samples per hour in just a few steps. Throughout the research, a mixture of 100 mM acetic acid:methanol:acetonitrile (70:15:15, v/v/v) was selected as an optimal background electrolyte for capillary electrophoresis - mass spectrometry analysis. Validation results of this method demonstrated its suitability, exhibiting good linearity (R2 > 0.95), low limits of detection (3.1-15 ng mL-1), acceptable precision (<15 %), and recovery for all tested analytes. Furthermore, the greenness evaluation conducted with six different metrics: AGREEprep, AGREE, ComplexGAPI, SPMS, hexagonal metric, and WAC indicated the overall eco-friendliness and sustainability of the method, with minor concerns regarding energy consumption.

SIGNIFICANCE

The use of cellulose paper with polystyrene membranes for μ-SPE provides a versatile and eco-friendly extraction method for detecting DRDs in urine samples. The presented work is an example of the use of GAC metrics in the evaluation of the analytical procedure. The optimized PT-μ-SPE/CE-MS method allows for minimized reagent usage and waste production. Moreover, the method proves to be sustainable and efficient for forensic toxicology analysis.

Optimization of mechanically assisted coamorphous dispersion extraction of hydrophobic compounds from plant tea (Citri Reticulatae Pericarpium) using water

This study aimed to establish a novel mechanically assisted coamorphous dispersion extraction (MADE) method for the extraction of hydrophobic compounds (hesperidin, nobiletin and tangeretin) from Citri Reticulatae Pericarpium using water. The surface morphology, particle size distributions, phase states and functional groups of the coground product surface were characterized by Scanning Electron Microscopy, X-ray diffraction and Fourier transform infrared spectroscopy. The parameters affecting the efficiency of extraction method were optimized by single-factor experiments and response surface methodology. The method showed good linear relationships in the range of 1-500 μg/mL with correlation coefficients (R²) ≥ 0.9990, low limits of detection ranging from 3.0 to 28.3 ng/mL, and acceptable recoveries ranging from 87.0 to 91.0%. Therefore, the proposed MADE method is a promising, efficient and organic solvent-free method for the extraction of hydrophobic compounds from plant tea.

Trace-level detection of sulfonamide antibiotics using quaternary ammonium polymeric ionic liquid-based effervescence-enhanced dispersive solid-phase extraction followed by LC-DAD analysis in environmental waters

Conventional ionic liquids possess several disadvantages, such as high viscosity, difficult sampling/retrieval, and great loss in aqueous solution, limiting their wide applications in the pretreatment field. To solve these drawbacks, we synthesized a quaternary ammonium polymeric ionic liquid (PIL) and pressed it into an effervescent tablet for developing an effervescence-enhanced dispersive solid-phase extraction method (QAP-EDSE). The pressed effervescent tablet was composed of PIL as an extractant, tartaric acid as an acidic source, NaHCO₃ as an alkaline source, and water-soluble starch as a filler, respectively. Under the CO₂-driven dispersion, the QAP-EDSE method integrated rapid enrichment, extraction, and dispersion into one synchronous step. Employing the one-factor-at-a-time approach, several important variables were optimized as follows: 200 mg of P[VBTHEA]Cl as sorbent, 400 μL of acetone as elution solvent, 5 min of elution, solution pH 9.0, and 1 : 1.25 molar ratio of alkaline to acidic sources. Combining LC-DAD analysis, this proposed approach offered the limits of detection as low as 0.11–0.31 μg L⁻¹ and satisfactory recoveries of 81.40–102.62% for five sulfonamides (SAs) in environmental waters. The lower relative standard deviations (1.9–6.7%) evidenced the higher intraday and interday experimental precision by this method. Overall, the newly developed method is environmentally benign, time-saving, and easy to operate with low detection limit and high recovery and thus shows excellent prospects in the trace-level detection of SAs in environmental waters.

An effervescent tablet-assisted dispersive solid-phase extraction based on the utilization of quaternary ammonium poly ionic liquids (PIL) was proposed for the concentration/extraction of sulfonamides (SAs) in river and lake water samples.

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.

Ultrasound-assisted hydrophobic deep eutectic solvent based solid-liquid microextraction of Sudan dyes in spice samples

An environmentally friendly, simple method was carried out with the help of an ultrasonic assisted solid-liquid microextraction technique using a new deep eutectic solvent (DES) for the extraction and determination of Sudan dyes (I-IV) in spice samples. In this method, parameters affecting the optimization were researched and optimized such as DES composition, DES volume, ultrasonic time, temperature and, centrifuge time. The analytical performance of the developed method was quite satisfactory, the R² values were higher than 0.9989, and the limits of quantification were <1.17 μg g^-1. Two different concentrations (10-50 μg g^-1) were spiked to Chili peppers, paprika, cumin and sumac spices for the applicability and accuracy of the developed microextraction method. Some of these spices were found to contain Sudan I and IV dyes. The recovery values for spiked samples were found to be between 85.55% and 99.29% and relative standard deviations were found to be <3.17% when using a 10 μg g^-1 Sudan dyes concentration. The results showed that the developed method can be successfully applied for extraction and determination of Sudan dyes in spice samples.

Development of magnetic porous carbon nano-fibers for application as adsorbents in the enrichment of trace Sudan dyes in foodstuffs

A novel kind of magnetic porous carbon nano-fibers (Fe₃O₄@P-CNFs) materials was successfully prepared and used as an adsorbent. Based on the above-mentioned adsorbent, a simple and effective magnetic disperse solid-phase extraction (MSPE) method was developed and first utilized to the enrichment and purification of five Sudan dyes (including Sudan I, Sudan II, Sudan III, Sudan IV, and Sudan Red 7B) in foodstuffs for the first time. High-performance liquid chromatography was used to determine the content of the Sudan dyes. The parameters affecting the extraction performance were studied and optimized, including the amount of the adsorbent and inorganic salt, type and the volume of the eluent, pH of the sample solution and extraction time. Under the optimized experimental conditions, the results show that the proposed method has a good linear relationship (r≥ 0.9993). The limits of detection range from 0.88 μg L^-1 to 1.27 μg L^-1. The recoveries range from 86.6% to 99.7% with the relative standard deviations ranging from 0.6% to 7.9% in the methodology validation. The above-mentioned results indicate that the proposed method is a sensitive and reliable procedure with good reproducibility for the detection of Sudan dyes residues in foodstuffs.

Dendrimer crown-ether tethered multi-wall carbon nanotubes support methyltrioxorhenium in the selective oxidation of olefins to epoxides

Benzo-15-crown-5 ether supported on multi-wall carbon nanotubes (MWCNTs) by tethered poly(amidoamine) (PAMAM) dendrimers efficiently coordinated methyltrioxorhenium in the selective oxidation of olefins to epoxides.

Dispersive micro-solid phase extraction based on Fe3O4@SiO2@Ti-MOF as a magnetic nanocomposite sorbent for the trace analysis of caffeic acid in the medical extracts of plants and water samples prior to HPLC-UV analysis

In this work, Fe₃O₄@SiO₂@Ti-MOF-NCs, as an efficient sorbent, have been synthesized in a laboratory and utilized for extracting CA in the medical extracts of plants and water samples before their analysis by HPLC.

Magnetic dispersive micro-solid phase extraction with the CuO/ZnO@Fe3O4-CNTs nanocomposite sorbent for the rapid pre-concentration of chlorogenic acid in the medical extract of plants, food, and water samples

CuO/ZnO@Fe₃O₄-CNTs-NC was synthesized and used as a sorbent in a MDMSPE method for the determination of chlorogenic acid in the medical extract of plants, food, and water samples.