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White pollution caused by the massive discharges of waste expanded polystyrene (WEPS) has become a critical global issue, so the effective conversion of WEPS is of great significance to reduce white pollution. Herein, adopting WEPS as raw material, three high-value-added hyper-crosslinked polymers (WEPS-HCPs) with high surface areas and abundant micro/mesoporous structures were synthesized via Friedel-Crafts alkylation reaction using dimethoxymethane, dichloroxylene and 4,4′-bis(chloromethyl)-1,1′-biphenyl (BCB) as cross-linker, respectively. The WEPS-HCPs were used as sorbent to extract aflatoxins (AFs) and all the HCPs exhibited high adsorption capacity. For the fast separation and recovery of the sorbent, WEPS-BCB was chosen as a model HCP to be magnetically functionalized to obtain a magnetic HCP (mWEPS-BCB) for the first time. Based on magnetic solid phase extraction with the mWEPS-BCB as sorbent, a fast and sensitive method was developed to determine trace level of AFs in grain food. Under the optimal conditions, the proposed method presented wide linear range (0.008–10.0 ng g−1), low detection limit (0.002–0.015 ng g−1) and satisfactory precision (relative standard deviation < 7%). Converting WEPS into a high-value-added sorbent not only provided a facile strategy for effective recycling of WEPS, but also developed a sensitive method for accurate determination of AFs in grain food, achieving significant economic and environmental benefits. [ABSTRACT FROM AUTHOR]

• Magnetic POF was prepared using tetraphenylethylene as building unit. • The M-POF showed excellent adsorption capability for nitromidazoles. • A sensitive method was established for extracting nitromidazoles in chicken meat. • The M-POF can serve as a promising adsorbent for other adsorption applications. A magnetic porous organic framework (M-POF) was rationally designed and served as a sorbent for magnetic solid-phase extraction of six nitroimidazoles from chicken meat prior to their assay by high-performance liquid chromatography with diode array detection. The M-POF exhibited good magnetic responsiveness and outstanding affinity to nitroimidazoles with large adsorption capacity up to 36 mg g−1. Under optimal conditions, the developed method offered good linearity (r greater than 0.992) in the range of 1.5–100.0 ng g−1, low limits of detection (S/N = 3) of 0.5–0.8 ng g−1, low limits of quantification of 1.5–2.5 ng g−1 and high enrichment factors of 80–175 for the nitroimidazoles. The method was successfully applied to analyze nitroimidazoles in chicken meat. The recoveries were 80.2–118% with relative standard deviations lower than 12%. The adsorption mechanism was further explored and the results showed that the M-POF exhibited adsorption potential for compounds with strong polar interactions. [ABSTRACT FROM AUTHOR]

Endocrine disrupting chemicals (EDCs) can interfere with the normal function of endocrine system, posing serious risk to human health. The monitoring of EDCs in foods is of great importance to ensure food security. Herein, a cyano and ionic dual-functionalized hypercrosslinked porous polymer (CN-iHCP) was designed and prepared for the first time through hyper-crosslink of 1-(4-cyanophenyl)imidazole and 1,4-bis(chloromethyl)benzene. The adsorption mechanism mainly involves electrostatic interaction, hydrogen bonding and π-π stacking interaction. A sensitive analytical method for simultaneous detection of the four phenolic EDCs was established by coupled CN-iHCP based solid-phase extraction with high performance liquid chromatography. Under optimal conditions, the target EDCs exhibited good linearity with coefficient r > 0.993 and high enrichment factors of 164–243. The detection limits (S/N = 3) of EDCs were 0.20–0.50 ng mL−1 for milk sample. The extraction recoveries for the spiked milk samples were in the range of 85.5%− 116.0%. This work not only highlights the CN-iHCP as a promising adsorbent to efficiently enrich EDCs and other pollutants, but also provides a new strategy for the functionalization of HCP for wide applications. [Display omitted] • Cyano and ionic dual-functional porous polymer (CN-iHCP) was synthesized. • CN-iHCP gave a large adsorption capacity and fast adsorption kinetics for EDCs. • Adsorption mechanism involved electrostatic force, hydrogen bond and π-π stacking. • A CN-iHCP based HPLC method was developed for sensitive detection of EDCs in milk. [ABSTRACT FROM AUTHOR]

Herein, two novel amino-functionalized triazine-based hyper-crosslinked porous polymer (NH 2 -HCPs) (named as DPT-BB, DPT-DX) were designed and synthesized by direct crosslinking of 2,4-diamino-6-phenyl-1,3,5-triazine (DPT) with 4,4′-bis(chloromethyl)-1,1′-biphenyl (BB) or α, α′-dichloro-p-xylene (DX). Thanks to the amino functional group and hyper-crosslinked porous structure, NH 2 -HCPs displayed remarkable adsorption ability for phenolic EDCs. The adsorption mechanism mainly involved hydrogen bond, π-π interaction, hydrophobic interaction and pore filling. Thus DPT-BB was applied as solid phase extraction sorbent to extract phenolic EDCs from water and orange juice samples prior to quantitative analysis by high performance liquid chromatography. Under the optimal conditions, detection limit as low as 0.07–0.2 ng mL−1 for water and 0.1–0.27 ng mL−1 for orange juice was achieved. Good recoveries spanned the range of 83.5%–114% were obtained for spiked samples, with relative standard deviations below 8.9%. The results demonstrated that the developed method displayed excellent practicability for sensitive analysis of EDCs. [Display omitted] • A novel amino-functionalized triazine-based HCP (DPT-BB) was successfully fabricated. • DPT-BB contains amino-functional groups and a highly cross-linked porous structure. • DPT-BB showed significant adsorption capacity to EDCs. • DPT-BB was applied to sensitive determination of EDCs in water and juice samples. • Hydrogen bond and π-π interaction played an important role in the extraction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multi-functionalized hypercrosslinked polymer (FBPA-PMDA) was prepared. • FBPA-PMDA showed excellent adsorption capacity to phenylurea herbicides. • FBPA-PMDA was used as solid phase extraction sorbent for phenylurea herbicides. • A sensitive analytical method was developed to determine four phenylurea herbicides. • The adsorption of phenylurea herbicides by FBPA-PMDA was driven by multiple forces. Wide use of phenylurea herbicide has caused serious residue problem and threaten human health. It is important to develop viable method for their sensitive determination. Herein, a multi-functionalized porous polymer was prepared by crosslinking hexafluorobisphenol A with pyromellitic dianhydride. Using the multi-functionalized porous polymer as solid phase extraction sorbent, combined with high performance liquid chromatography, a sensitive method was established for determining phenylurea herbicides in beverages and celtuces. High sensitivity was achieved, with method detection limit (S/N = 3) of 0.01–––0.025 ng mL−1 for beverages, 1.70 ng g−1 for celtuce, and quantitation limits of 0.03–––0.10 ng mL−1 for beverages, 5.00 ng g−1 for celtuce. The method recoveries were 80.5–––120.0 % with relative standard deviations lower than 6.1%. Adsorption mechanism mainly involved F-π, F-O, π-π, polar interactions and hydrogen-bonding interactions. This study offers a simple protocol to develop multi-functional sorbents for extraction of organic pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] In this work, a novel magnetic hyper-crosslinked polymers (EA-MHCP1) was facilely synthesized by using biogenic ellagic acid (natural polyphenol) as monomer for the first time. The EA-MHCP-1 showed high extraction capacity toward neonicotinoid pesticides. Thus, it was applied as efficient sorbent to simultaneously extract four of the most frequently used neonicotinoids from environmental water and lettuces, followed by high performance liquid chromatography-diode array detection. This work provided a fast, reliable and sensitive tool for neonicotinoids detection. • A novel magnetic HCP (EA-MHCP) was facilely synthesized using biogenic ellagic acid. • EA-MHCP showed large adsorption capacity and fast adsorption rate to neonicotinoids. • H-bond and Lewis acid-base interaction may be the main adsorption mechanism. • EA-MHCP was applied as MSPE sorbent to detect neonicotinoids in water and lettuce. • EA-MHCP exhibited good application prospect for organic compounds with big polarity. Three hydroxyl-functionalized magnetic hyper-crosslinked polymers (EA-MHCPs) were facilely synthesized using biogenic ellagic acid (EA) as monomer for the first time. The EA-MHCP1 possessed large surface area, good magnetism and excellent extraction capability toward neonicotinoids. Thus, an EA-MHCP1 based magnetic solid phase extraction method coupled with HPLC was developed for simultaneous analysis of four neonicotinoids in water and lettuce samples. At optimized conditions, excellent linear response (R2 ≥ 0.9990) was observed in the range of 0.06–100 ng mL−1 for water and 2.5–250 ng g−1 for lettuce. Low detection limits (S/N = 3) were obtained over the range of 0.02–0.03 ng mL−1 for environmental water and 0.8–3.2 ng g−1 for lettuce samples. Good method recoveries ranging from 80.0 % to 116 % were obtained, with relative standard deviations below 7.1 %. This work provided a robust analysis method for sensitively determining neonicotinoid residues in real samples. [ABSTRACT FROM AUTHOR]

• A novel hydroxyl-functionalized magnetic HCP was facilely synthesized. • M-HCP-HQ showed large extraction ability and fast adsorption rate to chlorophenols. • M-HCP-HQ was applied as MSPE sorbent to detect chlorophenols in water and honey. • A sensitive method was developed for simultaneously detecting four chlorophenols. • M-HCP-HQ showed good application prospect for organic compound with H-bond ability. Three hydroxyl-functionalized hypercrosslinked polymers (HCP-POL, HCP-HQ and HCP-PG) were synthesized by Friedel-Crafts reaction. The HCP-HQ displayed the largest surface area and highest adsorption capacity for chlorophenols (CPs). Thus, the HCP-HQ was further modified with magnetism to obtain M-HCP-HQ. An efficient magnetic solid-phase extraction method with M-HCP-HQ as adsorbent was developed for the first time to simultaneously extract four CPs from water and honey samples before analysis by high performance liquid chromatography-diode array detection. Under optimized conditions, the low detection limits (S/N = 3) were obtained to be 0.06–0.10 ng mL−1 for water and 0.80–1.75 ng g−1 for honey. The method recovery was 80.7%–119%, with relative standard deviations below 9.5%. The enrichment factors of the CPs were in the range of 57–220. The extraction mechanism could be attributed to the strong polar interaction, hydrogen bonding and π-π interactions between the M-HCP-HQ and CPs. The M-HCP-HQ based method can be served as a reliable and sensitive tool for detection CPs in water and honey samples. [ABSTRACT FROM AUTHOR]