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[Display omitted] • Synergistic effects of 1-octanol and COF@Tp-NDA improved bisphenols extraction. • Consumption of COF@Tp-NDA and organic solvents was less than existing methods. • HF porous structure avoided pollution of the extractant. • Method was successfully applied to the detection of BPs in three beverages samples. Bisphenols (BPs) can migrate from packaging materials into foods, resulting in potentially harmful residues. For example, accumulation of BPs is associated with endocrine disorders. Owing to matrix effects, development of an effective and eco-friendly sample pretreatment would be helpful for BPs detection in beverages packed in plastic containers. In this work, an extraction bar, composed of hollow fiber (HF) functionalized with covalent organic frameworks (COF@Tp-NDA) and 1-ocanol, was prepared for extraction of five BPs simultaneously. The synergistic effect of COF@Tp-NDA and 1-octanol improved the extraction efficiency of BPs from milk-based beverage, juice, and tea beverage. Under optimal conditions, limits of detection ranged from 0.10 to 2.00 ng mL−1 (R2 ≥ 0.9974) and recoveries ranged from 70.1 % to 106.8 %. This method has the potential to enrich BPs, supporting their accurate determination in complex beverages. [ABSTRACT FROM AUTHOR]

[Display omitted] • The composite beads (CACPs) were prepared facilely at room temperature. • CACPs can be completely separated within 1 min without centrifugation. • A convenient and sensitive method was developed for detecting neonicotinoids. • The developed method was successfully validated in fruit and vegetable samples. Neonicotinoids, the fastest-growing class of insecticides, have posed a multi-media residue problem with adverse effects on environment, biodiversity and human health. Herein, covalent organic framework-sodium alginate-Ca2+-polyacrylic acid composite beads (CACPs), facilely prepared at room temperature, were used in convenient dispersive solid-phase extraction (dSPE) and combined with high-performance liquid chromatography (HPLC) for the detection of five neonicotinoid insecticides (thiamethoxam, acetamiprid, dinotefuran, clothianidin, imidacloprid). CACPs can be completely separated within 1 min without centrifugation. After seven adsorption/desorption cycles, it maintained high extraction efficiencies (>90%). The developed method exhibited a wide linear range (0.01 ∼ 10 μg mL−1), low limits of detection (LODs, 0.0028 ∼ 0.0031 mg kg−1), and good repeatability (RSD ≤ 8.11%, n = 3). Moreover, it was applied to the determination of five neonicotinoids in fruit and vegetables (peach, pear, lettuce, cucumber, tomato), and recoveries ranged from 73.6% to 116.2%. [ABSTRACT FROM AUTHOR]

• Membrane-protected magnetic adsorbent was used for efficient extraction of estrogens. • The extraction efficiency was still above 90% after repeated use 10 times. • This developed method is simple, highly efficient and eco-friendly. The presence of estrogens residues in dairy products is a growing concern due to their potential health risk. Herein, in this study, we have developed a membrane–protected magnetic solid–phase extraction (MP–MSPE) method that utilized a magnetic adsorbent (Fe 3 O 4 @COF–LZU1) with in–situ growth for the efficient extraction of estrone (E1), 17β–estradiol (E2), and estriol (E3). When combined with HPLC–FLD, this method allows for the efficient detection of estrogens in dairy products. The stability of the MP–MSPE was improved by the presence of a dialysis membrane, which remained a high extraction efficiency (90 %) even after ten reuse cycles. The hydrogen bonding, π–π interactions and pore size effect contribute to the excellent adsorption of three estrogens onto Fe 3 O 4 @COF–LZU1. Under optimal conditions, the method exhibits a low detection limit (0.01–0.15 μg L−1), wide linear range (0.1–800 μg L−1), and favorable recoveries (77.3 %–109.4 %) at three concentration levels (10, 50 and 100 μg L−1). This proposed method is characterized by its simplicity, high efficiency and eco–friendliness, making it a promising approach for extracting estrogens from dairy products. [ABSTRACT FROM AUTHOR]

• Covalent organic framework TpBD grows on titanium wire via TiO 2 nanotube arrays. • TpBD-TiO 2 fiber has good thermal stability and long lifetime. • HS-SPME on the fiber exhibits excellent extraction efficiency for trace PAEs. • Coupled with GC-MS/MS, it presents a sensitive methodology for PAEs determination. Vegetables are easily contaminated by phthalate esters (PAEs) from the environment, agricultural films and fertilizers, affecting human health. In this paper, titanium dioxide (TiO 2) nanotube arrays were prepared by electrochemical anodic oxidation on the surface of titanium wire. Covalent organic framework of TpBD was in situ bonded to the titanium wire via TiO 2 nanotube arrays using monomers of 1,3,5-trimethylphloroglucinol (Tp) and benzidine (BD). The fabricated TpBD-TiO 2 coated titanium wire was used as the solid-phase microextraction fiber to extract 11 PAEs in vegetable samples. Coupled with gas chromatography-tandem mass spectrometry (GC–MS/MS), the limits of detection for PAEs were from 0.001 (di- n -butyl phthalate) to 0.430 (butyl benzyl phthalate) μ g/L (S/N = 3) and enrichment factors were between 226 (dimethyl phthalate) and 2154 (di- n -butyl phthalate). Our fabricated TpBD-TiO 2 fiber can be used at least 150 times without significant loss of extraction efficiency (<4.8%). Quantitative determination of PAEs in vegetable samples (tomato, lettuce, cucumber) was achieved by standard addition. [ABSTRACT FROM AUTHOR]