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Ionic liquid (IL)-modified UiO-66-NH2 composite was prepared and used as sorbent of dispersed solid-phase extraction (dSPE) for extracting trace benzoylurea insecticides (BUs) from complex environmental matrices. The IL in framework endowed the prepared material had electropositive characteristics, which can produce interaction with electron rich guest molecules, such as BUs. The high thermal and chemical stability of UiO-66-NH2/IL enabled it to be reused for 16 times without significant reduction in adsorption performance. Due to the multiple forces including π-π, hydrogen bonding, and fluorine-fluorine interaction, UiO-66-NH2/IL showed good adsorption performance, short adsorption time (20 s) and rapid desorption ability (60 s) for BUs. Under the optimal conditions, the method exhibited wide linear range (0.02–500 ng mL-1) with correlation coefficient (R2) not worse than 0.9928, high enrichment factor (252–300), and low detection limit (0.005–0.4 ng mL-1). The dispersed solid phase extraction coupling with high-performance liquid chromatography-diode array detector (dSPE-HPLC-DAD) was successfully used to detection of BUs in real environmental samples and satisfactory recoveries were obtained (80.5%±2.4–118%±3.2). The results indicated that UiO-66-NH2/IL composite can be a potential sorbent for the preconcentration of trace insecticides in environmental samples. [ABSTRACT FROM AUTHOR]

[Display omitted] • A magnetic multivariate MOF was synthesized by one-pot mixing ligand strategy. • 95.7 %BTB/MOF-525@Fe 3 O 4 was used as sorbent for adsorption and removal of bisphenols. • Maximum adsorption capacities ranging from 233.6 to 302.1 mg·g−1 for bisphenols. • The HPLC coupling with MSPE possesses low LODs with magnetic MTV-MOF as sorbent. • Sorbent exhibits excellent reusability with above 80% recovery after 21 times reuse. Herein, a magnetic multivariate metal–organic framework (MTV-MOF) named as 95.7 %BTB/MOF-525@Fe 3 O 4 was synthesized by one-pot mixing ligand strategy. The magnetic MTV-MOF exhibited large specific surface area (320 m2·g−1) and high porosity. The 95.7 %BTB/MOF-525@Fe 3 O 4 was used as sorbent for extraction and enrichment of bisphenol pollutants (BPs). The experimental results demonstrated that adsorption kinetics and isotherms conform to pseudo-second-order model and Langmuir model. The maximum adsorption capacities for bisphenol F, bisphenol A, bisphenol B, bisphenol AF were 275.1, 233.6, 302.1 and 277.2 mg·g−1, respectively. With 95.7 %BTB/MOF-525@Fe 3 O 4 as sorbent, the magnetic solid phase extraction coupling HPLC was used to detect trace BPs in environmental water. The limits of detection were determined as between 0.067 and 0.167 ng·mL−1. The enrichment factors were in the range of 242–295. The recoveries were ranged from 79.4 to 103 % with relative standard deviations not higher than 8.85 %. In addition, the recovery rate of sorbent remained above 80 % after 21 times of reuse. The work provides an effective material for extraction and removal of BPs in the environment. [ABSTRACT FROM AUTHOR]

Abstract Mesoporous silica nanoparticles (MSNs) have been widely studied as drug carriers to get sustained release behaviors, however, their application in sustained release of metoprolol tartrate (MPT) is limited. The possible reason is due to MPT molecule being bulky, while normal type MSNs like MCM-41 and SBA-15 have pore sizes of only 3–6 nm. In this study, two MCF-26 type MSNs were prepared with pore size of 11 or 15 nm, and used to conduct MPT release in comparison with MCM-41 and SBA-15. Both molecular simulation and MPT release experiments were performed to identify the pore size effect on adsorption and diffusion (release) of MPT in these MSNs. Finally, a kind of pH-sensitive MPT drug delivery system was obtained by coating the chosen MCF-26@MPT with an enteric polymer, which might find promising application in treating morning hypertension attack by orally administrating the drug delivery system before bedtime. Highlights • The adsorption and release of bulky metoprolol tartrate depend significantly on pore size of mesoporous silica. • Molecular simulation is helpful to determine the proper pore size for sustained release of metoprolol tartrate. • pH-Sensitive release of metoprolol tartrate from mesoporous silica is obtained via an enteric polyacrylic resin coating. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hierarchically porous Zr-based MOFs were prepared via modulator-induced strategy. • HP-NU-902-80 was used as sorbent to remove and enrich sulfonamide antibiotics (SAs) • The SAs can be completely removed within 10 min with HP-NU-902-80 as sorbent. • LODs and recoveries of the method were achieved at 0.08–0.25 ng/mL and 70.34–103.4 % • The maximum adsorption capacities of HP-NU-902-80 were 279.9–467.7 mg/g for SAs. Due to serious risk to human health and eco-environmental security, antibiotics in water and foods received considerable concern. Herein, a series of stable hierarchically porous zirconium-based metal–organic frameworks (MOFs) namely HP-NU-902-X were prepared via modulator-induced defect-guided formation strategy for the first time and functioned as sorbents to removal and preconcentration of sulfonamide antibiotics (SAs). The pore size and specific surface area of HP-NU-902-X were systematically adjusted by changing concentration of monocarboxylic acid modulator. The adsorption performance of HP-NU-902-X were greatly improved by forming defects. Experiments demonstrated that HP-NU-902-80 possessed the highest adsorption efficiency to SAs. The limits of detection (S/N = 3) were achieved ranging 0.08 to 0.25 ng/mL. The spiked recoveries of water and milk samples were obtained in the range of 70.34–103.4 % and 73.83–100.5 %. Enrichment factors were calculated between 203 and 358. The SAs can be completely removed within 10 min, and adsorption kinetic data was best consistent with pseudo-second-order model. Using Langmuir isotherm model, maximum adsorption capacities for sulfadiazine, sulfapyridine, sulfametoxydiazine, sulfachloropyridazine, sulfabenzamide and sulfamethazine were calculated as 279.9, 467.7, 414.4, 433.1, 415.5 and 336.6 mg/g, respectively. The improved adsorption capacity was mainly owing to high surface area and extra defect sites. This synthetic strategy provides a way to prepare stable defective MOFs and enhance their potential applications in removal and extraction of environmental pollutants. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flower-like Co 3 O 4 /C 3 N 5 nanocomposite was synthesized by one-pot solvothermal method. • The Co 3 O 4 /C 3 N 5 composite was used as fiber coating of solid-phase microextraction. • The Co 3 O 4 /C 3 N 5 as fiber coating exhibited high thermal stability (more than 400 ℃) • Good adsorption performance and high enrichment factors (3010–6180) were achieved. Sensitive detection of environmental pollutants that are harmful to organisms is of great significance for prevention of related diseases. In this work, a flower-like Co 3 O 4 /C 3 N 5 composite as solid-phase microextraction fiber coating was developed for extraction of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). The Co 3 O 4 /C 3 N 5 composite was derived from the multilayer stacked flower shaped Co(OH) 2 /C 3 N 5 that synthesized by one-pot solvothermal method. Compared with pure monomer materials, the unique structure was maintained and the surface adsorption sites were fully exposed, thereby the adsorption performances of Co 3 O 4 /C 3 N 5 were significantly improved. As a result, the enrichment factors were 3010–5012 for PAHs, and 4499–6180 for PCBs. Under the optimized conditions, the developed method showed wide linear range (0.0005–20 ng mL−1) with good linearity (R2 greater than 0.9912), low detection limits (0.00017–0.061 ng mL−1, S/N = 3) and quantification limits (0.0005–0.2 ng mL−1, S/N = 10) for three PAHs and five PCBs. The RSDs (n = 5) of intraday and interday were 2.28–8.35% and 3.49–9.59%, respectively. The reproducibility between fibers (n = 3) was in the range of 7.84–11.96%. The developed method was successfully applied to real water sample with satisfactory recoveries of 81.07–109.1%. As a simple and robust technique, the proposed method will be an alternative way to the analysis of PAHs and PCBs in real samples. [ABSTRACT FROM AUTHOR]