ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
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2019
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IF 4.527
Yi Chen Lu,Meng Han Guo,Jia Hao Mao,Xiao Hui Xiong,Yuan Jian Liu,Yi Li
A novel magnetic MIPs (DUMIPs) was prepared by surface molecular imprinting method using superparamagnetic core-shell nanoparticle (Fe 3 O 4 @SiO 2 ) as the sacrificial support matrix, herbicide diuron as template, α-methacrylic acid as the functional monomer , trimethylolpropane trimethacrylate as the crosslinker, azobisisobutyronitrile as the initiator, and acetonitrile as the porogen. Highly cross-linked porous surface and excellent magnetic property were characterized by Fourier-transform infrared spectroscopy, transmission electron microscopy , and vibrating sample magnetometer, respectively. The adsorption capacity of DUMIPs was 8.1 mg g −1 , 2.6-fold over its corresponding non-imprinted polymers (DUNIPs). The adsorption in DUMIPs was considered as multilayer adsorption and posed high affinity to diuron , due to the better fitting to Freundilich isotherm. Competitive recognition study demonstrated DUMIPs had highly selective binding diuron. DUMIPs, as an influential sorbent has been used for selective extraction of diuron from environmental samples (paddy field water, paddy soil and grain seedlings) and the elution was determined by high efficiency liquid chromatography (HPLC). In this analytical method, various factors affecting the extraction efficiency such as pH, sorbent dosage, utilization efficiency and volumes of eluent were simultaneously investigated. Under the optimal conditions, the linearity of the method obtained is in the range of 0.02–10.0 mg L −1 . The limit of detection is 0.012 mg L −1 . In four spiked levels (0.04, 0.2, 1.0, and 4.0 mg kg −1 ), the recoveries of diuron in real samples are in the range of 83.56%–116.10% with relative standard deviations in the range of 1.21–6.81%. Importantly, compared to C 18 -SPE column, the MMIPs exhibited convenient separation by external magnetic field, strong clean-up capacity, and selective enrichment for diuron. Thus, the DUMIPs-based method is great potential for efficient sample preparation in the determination of trace amounts of diuron residues in complex matrices.
研究领域:
分析化学
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环境科学
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DOI
PubMed
高影响因子
CHINESE CHEMICAL LETTERS
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2017
·
IF 1.932
Muhammad Ammar,Yan Cao,Peng He,Li-Guo Wang,Jia-Qiang Chen,Hui-Quan Li
A set of mono- and bimetallic (Zn-Co) supported ZSM-5 catalysts was first prepared by PEG-additive method. The physicochemical properties of the catalysts were investigated by FTIR, XPS, XRD, N 2 adsorption-desorption measurements, SEM, EDS and NH 3 -TPD techniques. The physicochemical properties showed that the ZnCo 2 O 4 spinel oxide was formed on the ZSM-5 support and provided effectual synergetic effect between Zn and Co species for the bimetallic catalyst. Furthermore, bimetallic supported ZSM-5 catalyst exhibited weak, moderate and strong acidic sites, while the monometallic supported ZSM-5 catalyst showed only weak and moderate or strong acidic sites. Their catalytic performances for thermal decomposition of hexamethylene–1,6–dicarbamate (HDC) to hexamethylene–1,6–diisocyanate (HDI) were then studied. It was found that the bimetallic supported ZSM-5 catalysts, especially Zn-2Co/ZSM-5 catalyst showed excellent catalytic performance due to the good synergetic effect between Co and Zn species, which provided a suitable contribution of acidic sites. HDC conversion of 100% with HDI selectivity of 91.2% and by-products selectivity of 1.3% could be achieved within short reaction time of 2.5 h over Zn-2Co/ZSM-5 catalyst.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2016
·
IF 5.31
Qihang Yi,Lingjun Bu,Zhou Shi,Shiqing Zhou
In this paper, epigallocatechin-3-gallate/Fe 3 O 4 , a novel heterogeneous catalyst to activate peroxymonosulfate for diuron degradation, was synthesized and its structure was well characterized by transmission electron microscopy, X-ray diffraction, Fourier transform infrared, and X-ray photoelectron spectroscopy. It was found that the hybrid catalyst showed a better catalytic efficiency than both Fe 3 O 4 and epigallocatechin-3-gallate. This was resulted from the high reduction ability of epigallocatechin-3-gallate, which promoted the cycle of Fe(III)/Fe(II) on the surface of catalyst. Besides, batch experimental results showed that the degradation of diuron depended upon the dosage of catalyst and oxidant, initial pH, and co-existed humic acid. Results demonstrated that high catalyst and oxidant dosages, low initial pH and humic acid were favorable for diuron removal. Furthermore, by adding different dosages of methanol and tertiary butanol, two kinds of radicals were detected to be responsible for diuron degradation in this study and sulfate radical made the predominant contribution. At last, mineralization and degradation pathway were also evaluated in this study. Anyway, it was confirmed that the as-prepared catalyst has the potential superiority for contaminants removal from aqueous solution.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
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2025
·
IF 4
Jing Lin,Dan Li,Peiyuan Luo,Laisheng Li
we reported a new phenylcarbamoylethylenediureido-β-cyclodextrin CSP (PUCDP) for HPLC, which was conveniently prepared by immobilizing the addition product of diethylenetriamino-β-CD with 3,5-dichlorophenyl isocyanate onto silica gel. After structural characterization, the chromatographic performance of PUCDP was preliminarily evaluated by using common 11 triazole pesticides as probes. The results showed that PUCDP had strong chiral separation abilities for all triazoles ( R s=1.44–3.70). Especially, it could first completely separate triazoles with two chiral centers such as cyproconazole, triadimenol, metconazole, paclobutrazol and bitertanol, into four peaks, respectively. Some effects on the separation and detection were investigated, including the composition of mobile phase, pH value, column temperature, and absorption wavelength. Based on comprehensive optimization of chromatographic conditions and a homemade PUCDP column, we established a new method for the simultaneous separation and determination of twelve triazole pesticide enantiomeric residues (flutriafol, cyproconazole, tebuconazole, and metconazole) in nine kinds of fruits and vegetables (apple, banana, orange, pear, cucumber, green pepper, tomato, wax gourd, cabbage). After simple QuEChERS pretreatment, samples were analyzed under the optimized conditions of a gradient elution program with acetonitrile-water (ACN H 2 O) containing 0.5 % triethylammonium acetate (TEAA) buffer (pH=6.30) as the mobile phase at a flow rate of 0.5 mL min -1 , a photo-diode array (PDA) detector at 220 nm, column temperature at 20 °C and an injection volume of 20 μL. The method exhibited good linear relationship ( R 2 =0.9941–0.9999) in the range of 0.5–60 mg l -1 for all triazole enantiomers. The limits of detection (LODs) and limits of quantification (LOQs) ranged from 0.05 to 0.10 mg kg -1 and 0.15 to 0.30 mg kg -1 , respectively. The average recoveries of all enantiomers were 81.60 %-104.08 % with intra -day and inter -day relative standard deviations (RSDs) of 1.91 %-3.50 % ( n = 5) and 2.05 %-4.49 % ( n = 15), respectively. The determination of 54 actual samples indicated the practicality of the method. This simultaneous determination method could save analysis time, and reduce solvent consumption with high analysis efficiency. The excellent performance of PUCDP was mainly related to the rich hydrogen bonds (donors and acceptors), the large π-π stacking and the extended cavity derived from the diphenylurea groups, which was consistent with the results of AutoDock molecular docking.
研究领域:
分析化学
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色谱技术
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农药残留分析
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食品安全
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手性分离技术
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DOI
PubMed
高影响因子
Materials Science & Engineering C-Materials for Biological Applications
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2019
·
IF 4.959
Xiaolong Liu,Bing Yang,Zhaosheng Hou,Na Zhang,Yuanyuan Gao
The aim of this work is to provide a new kind of polyurethane with improved surface blood compatibility for long-term blood-contacting biomaterials. In the study, an aliphatic poly(ester-urethane) (H-PEU) with uniform-size hard segments was synthesized by one-step chain extension of poly(ε-caprolactone) (PCL) with diurethane diisocyanate (HBH), and biomimetic phosphorylcholine (PC) groups were immobilized onto the film surface with high grafting efficiency by three-step chemical treatments under mild reaction conditions. The H-PEU film was firstly treated with 1,6-hexanediisocyanate (HDI) to introduce -NCO groups on the surface (H-PEU-NCO) through an allophanate reaction; the -NCO groups were then coupled via a condensation reaction with one of -NH 2 groups of tris(2-aminoethyl)amine (TAEA) to immobilize -NH 2 on the surface (H-PEU-NH 2 ); finally, the double bond of 2-methacryloyloxyethyl phosphorylcholine (MPC) reacted with -NH 2 by Michael addition reaction to obtain MPC-grafted H-PEU (H-PEU-MPC). The modified surfaces were characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The results verified that MPC was successfully grafted onto H-PEU surface with high grafting density. The blank and modified films showed similar crystallization behaviors, thermal stabilities and mechanical properties, indicating that the chemical treatments had minimum influence on the physicochemical properties of the substrate. The H-PEU-MPC displaying a much lower water contact angle (~15.2°) than H-PEU (80.3°) meant that the hydrophilic PC functional groups improved the surface hydrophilicity significantly. The surface blood compatibility was examined by bovine serum albumin adsorption and platelet adhesion tests, and the results revealed that H-PEU-MPC had improved resistance to protein adsorption and platelet adhesion capacity. The MPC-grafted H-PEU film possessed outstanding mechanical properties (ultimate stress: 36.1 MPa; strain at break: 883%), low protein adsorption quantity (1.33 μg/cm 2 ) and good anti-platelet adhesion capacity (582 ± 16 per mm 2 ), implying its high potential to be applied as biomaterials for vascular grafts, subcutaneously implanted devices or other blood-contacting devices.
研究领域:
生物材料
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表面化学
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生物医学工程
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材料科学
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PubMed
高影响因子
Analytical Methods
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2021
·Vol. 13
·期 17
·2005-2010
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IF 2.896
Tianlin Wang,Yaqing Liu
Organophosphorus pesticides (OPs) residues have caused great concern as they cause great harm to public health. Herein, a ratiometric fluorescent sensing system was developed for the OPs detection with the merits of enzyme-free, simple operation, short-time and sensitivity. The change in the fluorescence signal in the sensing system was provided by guanine-rich DNA (G-DNA) and silver nanoparticles (AgNPs) with terbium ion (Tb3+) and dured. Tb3+ coordinated with the G-DNA to form a DNA–Tb complex to emit green fluorescence, which can be significantly enhanced by AgNPs based on the mechanism of metal enhanced fluorescence. Dured embedded into the G-DNA emits red fluorescence as the built-in fluorescence signal. After adding OPs into the DNA–Tb–dured–AgNPs sensing system, the fluorescence of Tb3+ quenched, while the fluorescence of dured remained unchanged. The OPs detection is implemented enzyme-free or label-free and has the advantage of high sensitivity and reliability. The limit of detection reaches as low as 0.034 μg L−1, and good recoveries are obtained for the OPs detection in tap water and apple. Moreover, the developed sensing system is simple in preparation and low cost, exhibiting an efficient platform to meet the requirement for in situ application in food safety and environmental monitoring.
研究领域:
分析化学
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环境科学
·
食品安全
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）