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[Display omitted] • DFT calculations and experiments are combined to tunne cation types of LDHs. • CaAl-LDH has highest Cl- adsorption capacity, aligned with lowest binding energy. • CaAl-NO 3 -LDH transforms into Friedel's salt after reacted with Cl- • ZnAl-LDH retains the most Cl- after addition of SO 4 2- with crystallinity improved. • Divalent cations dominate LDHs' interlayer spacing and binding energy in some cases. Layered double hydroxides (LDHs) are new concrete additives that improve Cl- sorption capacity by varying their chemical composition. In this work, first-principles calculations were used to design the chemical compositions of LDHs with various cations. Accordingly, four cation types of LDHs (CaAl, MgAl, MgFe and ZnAl) were selected to be synthesized, their Cl- sorption kinetics were further measured. The objective was to establish a high-throughput screening approach to identifying the most promising cations for enhancing the sorption capacity of LDHs towards Cl-. Results revealed that the absolute value of Cl- binding energy increased as the interplanar spacing of different LDHs decreased from first-principles calculations. Particularly, CaAl exhibited the highest adsorption capacity for Cl- (3.25 mmol/g) from experiments, validating the simulation results that it has the highest absolute value of Cl- binding energy. MgFe-Cl-LDH has the smallest absolute value of Cl- binding energy with the lowest adsorption capacity for Cl- as well as the crystallinity. Moreover, multiple factors influencing the Cl- sorption ability of LDHs, such as chemical composition, crystallinity, microstructures and their synergistic effects, are discussed thoroughly based on the experimental results. This study established a connection between the simulation and experimental approaches in understanding the mechanism of Cl- adsorption. [ABSTRACT FROM AUTHOR]

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]

To develop ion exchangers of high protein adsorption capacity, we have herein introduced atom transfer radical polymerization (ATRP) method to graft glycidyl methacrylate (GMA) onto Sepharose FF gel. GMA-grafted Sepharose FF resins of four grafting densities and different grafting chain lengths were obtained by adjusting reaction conditions. The epoxy groups on the grafted chains were functionalized by modification with diethylamine (DEA), leading to the fabrication of Sepharose-based anion exchangers of 14 different grafting densities and/or grafting chain lengths. The resins were first characterized for the effects of grafting density, chain length and ionic strength on pore sizes by inverse size exclusion chromatography. Then, the resins were evaluated by adsorption equilibria of bovine serum albumin (BSA) as a function of ionic capacity (IC) (chain length) at individual grafting densities. It was observed that at each grafting density there was a specific IC value (chain length) that offered the maximum equilibrium capacity. Of the resins with maximum values at individual grafting densities, the resin of the second grafting density with an IC value of 330 mmol/L (denoted as FF-Br2-pG-D330) showed the highest capacity, 264 mg/mL, about two times higher than that of the traditional ungrafted resin Q Sepharose FF (137 mg/mL). This resin also showed the most favorable uptake kinetics among the resins of similar IC values but different grafting densities, or of the same grafting density but different IC values. Effects of ionic strength showed that the capacities of FF-Br2-pG-D330 were much higher than Q Sepharose FF at a wide range of NaCl concentrations (0–200 mmol/L), and the uptake rates of the two resins were similar in the ionic strength range. Therefore, the dynamic binding capacity values of BSA on FF-Br2-pG-D330 were much higher than Q Sepharose FF as demonstrated at different residence times and ionic strengths. Taken together, the research has proved the success in the fabrication of high-capacity protein anion exchangers by grafting GMA onto Sepharose gel. [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]

Water pollution caused by bisphenol A (BPA) has become the world problem. Designing and preparing cost-effective and biodegradable sorbents for the effectively adsorptive removal of bisphenol A from wastewater is of immense significance. Herein, a natural polysaccharide (chitin) was used as raw materials to be grafted with styrene (GS), then crosslinked with α,α'-dichloro-p-xylene (DCX) to form the hyper-crosslinked polymer (labeled as CGS@DCX). The CGS@DCX showed high adsorptive affinity for bisphenol A, with adsorption capacity of 441 mg g−1. Various studies gave an insight into the adsorption process, demonstrating that the highly efficient adsorption of BPA by the CGS@DCX is mainly based on the π-π stacking, hydrogen-bond interaction, polar interaction and pore adsorption. Moreover, the CGS@DCX had high chemical stability, good reusability (9 cycles) and fast adsorption kinetics (10 min) for adsorption of BPA. This work provides a promising strategy for the design and synthesis of novel yet eco-friendly sorbents to solve environmental problems. • A bio-sorbent, CGS@DCX, is prepared using natural chitin as raw material. • CGS@DCX displays large adsorption capacity and fast adsorption rate towards BPA. • Multiple interaction forces promote the BPA adsorption on the CGS@DCX bio-sorbent. • The CGS@DCX exhibited good application prospect for removal of other pollutants. [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]

Bisphenol A (BPA) as an endocrine-disrupting chemical has been widely detected in the aquatic environment, including Taihu Lake, China. Adsorption and bacterial removal in sediments play important roles in the fate of BPA in the aquatic environment, which might be influenced by the properties of the sediment. In this study, two types of sediments from Gonghu Bay and Meiliang Bay in the northern Taihu Lake were collected to investigate the fate of BPA in the sediments. Both sediments showed different adsorption properties to BPA. Due to the higher proportion of sand and total organic carbon (TOC) content in the Meiliang Bay sediment, its adsorption capacity was stronger than that in the Gonghu Bay sediment. Bacteria in both sediments could completely degrade BPA within 3–5 days. Based on the correlation analysis, Firmicutes and Cyanobacteria might be involved in BPA removal at the phyla level. At the genus level, Novosphingobium , Massilia, and Methylophilus were found to be related to the BPA removal in the Gonghu Bay sediment, and Acinetobacter , Bacillus and Pseudomonas were found in the Meiliang Bay sediment. The different bacterial communities might be important reasons for the different removal capacity of BPA in both sediments. The above results provide basic information for the assessment and management of BPA in the Taihu Lake, and improve the understanding of BPA removal in sediments. • BPA adsorption in Meiliang Bay sediment was faster than Gonghu Bay sediment. • Bacteria in both sediments effectively degraded BPA within 3–5 days. • Bacteria that were high correlation with BPA degradation were identified. • Community structure of bacteria influenced the degradation process of BPA. [ABSTRACT FROM AUTHOR]

In the present work, a nanoscale porous surface was gradually prepared on Ti surface by two-step method of acid corrosion and NaOH–H 2 O 2 mixing treatment. This led to the formation of a TiO2 coating at the surface of the underlying Ti substrate. Then, silver nanowires were deposited on the nanostructured surface by spin-coating technology. The nanowires were found to be evenly introduced into the nanostructured TiO2 coating. The modified Ti surface showed good wettability and protein adsorption capacity. More importantly, in-vitro cellular and bacterial assays indicated that the modified Ti surface possessed not only the excellent adhesion and differentiation abilities for osteoblasts but also relatively strong antimicrobial capacities for both S. aureus and E. coli. The results suggest that such modified Ti surfaces greatly prefer the initial adhesion of osteoblast-like cells over the initial adhesion of bacteria. The surface modification that we made to Ti substrate can promisingly meet clinical requirements. [ABSTRACT FROM AUTHOR]

• A novel phosphate-functionalized magnetic POP were synthesized for the first time. • M-DBP-POP showed fast adsorption rate and high adsorption capacity to neonicotinoids. • A M-DBP-POP based MSPE-HPLC method was developed to determine four neonicotinoids. • Hydrogen bond, π-π and hydrophobic interactions were the main adsorption forces. • M-DBP-POP holds great application potential in the adsorption/separation field. There is an urgent need to prepare advanced functional materials for extraction and enrichment of trace organic pollutants from different samples. In this work, two novel phosphate-functionalized porous organic polymers (DBP-POP and DPP-POP) were synthesized for the first time. Compared with phosphate-free counterpart, both phosphate-functionalized POPs showed excellent adsorption performance for the neonicotinoids due to the hydrogen bonding, π-π interaction and hydrophobic interaction. For ease of separating the sorbent from solution, magnetic DBP-POP (M-DBP-POP) was further prepared as sorbent to extract neonicotinoids from environmental water and lemon juice samples prior to their determination by high performance liquid chromatography-ultraviolet detection. Under optimal conditions, the detection limits (S/ N = 3) of the method were 0.01–0.08 ng mL−1 for water and 0.03–0.10 ng mL−1 for lemon juice. The recoveries were in the range of 80.0% to 113.0% with relative standard deviation less than 10.6%. This work demonstrated the feasibility of phosphate-functionalized POPs for adsorption applications. [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]