Preparation of cationic microporous organic network for efficient solid-phase extraction of nonsteroidal anti-inflammatory drugs from environmental water and milk samples

The overuse of nonsteroidal anti-inflammatory drugs (NSAIDs) poses many serious environmental and food safety concerns. Development of effective and sensitive sample pretreatment method for monitoring trace NSAIDs from complex samples is of great significance. Depending on the ionic and aromatic structures of NSAIDs, a cationic microporous organic network (MON) named TEPM-BBDC with large specific surface area, good solvent and thermal stabilities, and numerous interaction sites was designed and prepared for efficient solid-phase extraction (SPE) of four typical NSAIDs (flurbiprofen, ketoprofen, naproxen, and diclofenac sodium) from environmental water and milk samples. By anchoring the ionic groups in the conjugated MON frameworks, the prepared TEPM-BBDC offered good extraction for NSAIDs based on the π-π, hydrophobic, ion exchange, and electrostatic interactions. Under the optimal extraction conditions (initial concentration of each NSAID: 200 g L-1; sample volume: 50 mL; desorption solvent: 1.5 mL of MeOH + 1 % NH3·H2O; sample loading rate: 5 mL min-1; NaCl concentration: 0 mmol L-1; pH = 5), the proposed TEPM-BBDC-SPE-HPLC-UV method owned wide linear range (0.50-1000 g L-1), low limits of detection (0.10-0.40 g L-1), large enrichment factors (92.2-99.2), good precisions (intra-day and inter-day, RSD% = 1.3-7.8 %, n = 6) and reproducibility (column-to-column, RSD% = 8.0 %, n = 3). The developed method also exhibited good recoveries (83.6-113.4 %) for the determination of NSAIDs in river water, lake water and milk samples. This work not only revealed the potential of TEPM-BBDC for SPE of ionic NSAIDs in complex samples, but also highlighted the prospect of ionic MONs in sample pretreatment.

Facile and efficient preparation of amino bearing metal-organic frameworks-coated cotton fibers for solid-phase extraction of non-steroidal anti-inflammatory drugs in human plasma

The determination of blood concentration of non-steroidal anti-inflammatory drugs (NSAIDs) is highly desired in clinical practice. In this work, three amino bearing metal-organic frameworks (amino-MOFs) coated cotton fibers were prepared using a facile cysteine-triggered in situ growth strategy and proposed as in-tip solid-phase microextraction (in-SPME) adsorbents for efficient extraction of non-steroidal anti-inflammatory drugs from human plasma. The self-made adsorbents exhibited satisfactory extraction performance toward three NSAIDs including diclofenac sodium, ketoprofen and flurbiprofen. Under the optimized conditions, the established method exhibited satisfactory enrichment performance, low limits of detection and excellent extraction efficiency. Good reproducibility, wide linear range, excellent linearity and satisfactory sensitivity were obtained in the experiment. The method was also used for the enrichment and determination of NSAIDs in human plasma samples. Good recoveries were obtained, ranging from 66.5% to 98.9% with relative standard deviations less than 6.62%. The good performance of amino-MOFs was due to the synergistic effects arising from grafted charged amino groups within ordered pores of suitable size, leading to strong affinity towards guest molecules. Electrostatic interaction, hydrogen bond and π-π interaction played a vital role in the extraction of NSAIDs. This report indicated the potential of amino-MOFs as efficient adsorbents for the determination of NSAIDs from human plasma.

Hydrophilic carboxyl supported immobilization of UiO-66 for novel bar sorptive extraction of non-steroidal anti-inflammatory drugs in food samples

Herein, the preparation of UiO-66 on frosted glass rod (FGR) was proposed through the coordination interaction of Zr-OH groups and carboxyl sites on FGR. The relative standard deviations (RSDs) of intra-batch and inter-batch were below 8.0% (n = 7). UiO-66-modified FGR (UiO-66@FGR) was applied to the extraction and monitoring of five non-steroidal anti-inflammatory drugs (NSAIDs) by coupling to novel bar sorptive extraction (BSE) with ultra-high performance liquid chromatography (UPLC). Sample volume, stirring rate, extraction time, sample pH value, desorption solvent, and desorption time were investigated. NSAIDs (ketoprofen, flurbiprofen, ibuprofen, naproxen, and diclofenac sodium) were determined at a low limit of detection (0.92 ng/mL) over a wide linear range (10-1500 ng/mL). The developed method was used to analyze NSAIDs in sheep muscle, chicken wing, and milk with recoveries of 80.8%-117.2%, RSDs < 6.5%. Fabricated UiO-66@FGR exhibited excellent reproducibility, stability, and good adsorption property towards NSAIDs in food samples.

3D flower-liked Fe3O4/C for highly sensitive magnetic dispersive solid-phase extraction of four trace non-steroidal anti-inflammatory drugs

A low cost-effective and simple synthesis method was adopted to acquire three-dimensional flower-like structure Fe₃O₄/C that has large specific area, suitable pore structure and sufficient saturation magnetism. The obtained Fe₃O₄/C exhibits outstanding preconcentration ability and was applied to extracting non-steroidal anti-inflammatory drugs from complex environmental and biological samples. The parameters of magnetic solid-phase extraction were optimized by univariate and multivariate methods (Box-Behnken design). The high degree of linearity from 2.5 to 1000.0 ng mL^-1 (R² ≥ 0.9976), the limits of detection from 0.25 to 0.5 ng mL^{- 1} (S/N = 3), and the limits of quantitation from 1.0 to 2.0 ng mL^{- 1} (S/N = 10) were yielded by adopting this novel method after the optimization. Moreover, the recoveries of non-steroidal anti-inflammatory drugs from 89.6 to 107.0% were acquired in spiked plasma, urine and lake samples. In addition, the adsorption of non-steroidal anti-inflammatory drugs on Fe₃O₄/C was explored by adsorption isotherms and kinetic studies. Furthermore, the adsorption mechanism for non-steroidal anti-inflammatory drugs by Fe₃O₄/C was proposed, which was hydrogen bonding and π-π interaction between non-steroidal anti-inflammatory drugs and Fe₃O₄/C. Graphical abstract.

A fast and simple air-assisted liquid-liquid microextraction procedure for the simultaneous determination of bisphenols, parabens, benzophenones, triclosan, and triclocarban in human urine by liquid chromatography-tandem mass spectrometry

The increasing awareness and public concern with hazard exposure to endocrine-disrupting chemicals calls for methods capable to handle numerous samples in short analysis time. In this present study, a novel method combining air-assisted liquid-liquid microextraction and liquid chromatography coupled to mass spectrometry was developed and validated for the extraction, preconcentration, and determination of 7 bisphenols (bisphenol A, bisphenol S, bisphenol AP, bisphenol P, bisphenol F, bisphenol AF, bisphenol Z), 7 parabens (methyl-, ethyl-, propyl-, butyl-, benzyl-paraben, methyl-protocatechuic acid, and ethyl-protocatechuic acid), 5 benzophenones (benzophenone-1, benzophenone-2, benzophenone-3, benzophenone-8, and 4-hydroxybenzophenone), and two antimicrobials (triclosan and triclocarban) in human urine samples. Type and volume of solvent, extraction time (cycles), pH sample, ionic strength, agitation, and needle dimensions were evaluated. The matrix-matched calibration curves of all analytes were linear with correlation coefficients higher than 0.99 in the range level of 1.0-20.0 ng mL^-1. The relative standard deviation, precision, at three concentrations (1.0, 10.0 and 20.0 ng mL^-1) was lower than 15% with accuracy ranging from 90% to 114%. The biomonitoring capability of the new proposed method was confirmed with the analysis of 50 human urine samples randomly collected from Brazilian children. High urinary concentrations of several EDCs associated with usage of personal care products were found.