MICROCHIMICA ACTA
·
2015
·Vol. 182
·期 15
·2419-2425
·
IF 3.741
Feng Zhongmin,Guo Tingting,Jiang Zhiwen,Sun Ting
We have investigated the possibility of sampling ammonium ion using the diffusive-gradients-in-thin-films technique (DGT) by introducing a novel binding agent that is based on micro-sized zeolite. The performance of zeolite-DGT was characterized by measurement of the following parameters: (1) the diffusion coefficient of ammonium ion in hydrogel; (2) the adsorption rate of ammonium ion by the zeolite binding gel; (3) the elution efficiency, and (4) the effects of pH, ionic strength and interfering ions on DGT. The method was validated by studying the uptake of ammonium ion from in freshwaters by zeolite gels which was found to be fast enough to meet the requirements of DGT. The concentrations determined via DGT agreed well with the concentrations determined in bulk solutions. Sampling of ammonium ion using zeolite-DGT was consistent over the pH 3 to 8 range and the 0.001 to 10 mM ionic strength range. The method also performs predictably in natural waters containing various metal ions. The technique is considered to be a viable passive tool for sampling ammonium from aqueous solutions.
Schematic representation of the principle of DGT and the determination of mass accumulated on the binding gel.
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高影响因子
COLLOID AND POLYMER SCIENCE
·
2015
·Vol. 293
·期 7
·2121-2128
·
IF 1.865
Gong Huameng,Xie Zhifei,Liu Mingxing,Sun Honghao,Zhu Hongda,Guo Huiling
In this paper, mesoporous silica nanoparticles (MSNs) functionalized with polyethylene glycol (PEG, Mw = 1000 and 5000 Da) via a disulfide bond linker (named as MSNs-SS-PEG 1000 and MSNs-SS-PEG 5000 , respectively) as the novel drug delivery carrier was successfully synthesized. The particle size, surface structural properties, and pore size of these materials were investigated by dynamic light scattering (DLS), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), nitrogen adsorption–desorption measurements, and X-ray diffraction (XRD). Both MSNs-SS-PEG 1000 and MSNs-SS-PEG 5000 exhibited the spherical particles with an average diameter of about 200 nm, typical micropore structures, and intact pore interconnection. Moreover, the releases of doxorubicin hydrochloride (DOX) from these materials in different concentrations of glutathione (GSH) were investigated. The release of DOX from MSNs-SS-PEG 1000 and MSNs-SS-PEG 5000 revealed the redox-responsive characteristic and the drug release content increased with the increase of GSH concentration. Therefore, MSNs-SS-PEG might be a promising carrier material in delivering anticancer drugs.
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高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2015
·Vol. 50
·期 14
·4914-4925
·
IF 2.371
Cheng Cui,Xia Dandan,Zhang Xiuli,Chen Li,Zhang Qiqing
The therapeutic concentration of cisplatin (CDDP) is usually associated with dose-limiting side effects. To avoid these harmful effects, a biocompatible hydrogel carrier which consisted of poly( N -isopropylacrylamide) and carboxymethyl chitosan was designed to deliver CDDP to the local environment of a solid tumor. The poly( N -isopropylacrylamide)-g-carboxymethyl chitosan hydrogels were synthesized by chemical crosslinking. Scanning electronic microscopy images showed that the hydrogels exhibited a cross-linked structure with the average pore size from 100 to 200 µm. Water contact angles and swelling studies suggested that the hydrogels had good hydrophilicity and the lower critical solution temperature lay in the vicinity of 32 °C. The MTT assays implied that the hydrogels were non-cytotoxic on NIH3T3 cells. In vitro release experiment demonstrated that the release of CDDP was controllable and sustained over a long period. Moreover, the released CDDP retained its anticancer activity on A549 cells. The hydrogels are promising carriers for sustained release of cisplatin.
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高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2015
·Vol. 17
·期 2
·1-11
·
IF 2.184
Zhang Yan,Lin Xia,Du Xuli,Geng Sicong,Li Hongren,Sun Hong,Tang Xing,Xiao Wei
In this work, we designed and developed a delivery system composed of enteric Eudragit L100-cysteine/reduced glutathione nanoparticles (Eul-cys/GSH NPs) for oral delivery of insulin. First, interactions between Eul-cys and mucin glycoproteins, which are believed to be the result of disulfide bonds, were confirmed using rheology experiments. Subsequently, the insulin-loaded Eul-cys/GSH NPs were prepared by the diffusion method using the rich gel network multipore structure at the surface of the Eul-cys when the pH was higher than the p K a of Eul-cys polymer. The Eul-cys/GSH NPs obtained were characterized by dynamic light scattering, transmission electron microscopy, and atomic force microscopy. The results obtained showed that the average particle size ranged from 240 to 280 nm, and the particles were almost spherical in shape. The in vitro drug release results showed that the Eul-cys/GSH NPs retained a large amount of insulin in simulated gastric fluid, while a significant insulin release was found in simulated intestinal fluid. The in situ release study suggested that NPs released a greater amount of FITC-insulin (49.2 %) into the intestinal mucus layer compared with that of FITC-insulin solution (16.4 %), which facilitating insulin delivery through the intestinal mucosa. Eul-cys/GSH NPs exhibited promising mucoadhesive properties demonstrated using an in vitro cell model. Consequently, NPs were introduced into the ileum loop of healthy rats, thus enhancing the intestinal absorption of insulin and providing a prolonged reduction in blood glucose levels. These results suggest that Eul-cys/GSH NPs may be a promising delivery system for the treatment of diabetes.
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高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2015
·Vol. 22
·期 13
·10107-10115
·
IF 2.828
Wang Guanghui,Wang Yin,Hu Suhang,Deng Nansheng,Wu Feng
It is necessary to find an effective soil remediation technology for the simultaneous removal of hydrophobic organic contaminants and heavy metals from contaminated soils. In this work, a novel cysteine-β-cyclodextrin (CCD) was synthesized by the reaction of β-cyclodextrin with cysteine, and the structure of CCD was confirmed by 1 H-NMR, 13 C-NMR, FT-IR spectroscopy and elemental analysis. Pot-culture experiments were conducted to investigate the effects of CCD on the phytoremediation of soil co-contaminated with phenanthrene and lead. The results showed that CCD can enhance the phytoremediation of soil co-contaminated with phenanthrene and lead. When CCD was added to the co-contaminated soil, the concentrations of phenanthrene and Pb in roots and shoots of ryegrass ( Lolium perenne L . ) significantly increased, the presence of CCD is beneficial to the accumulation of phenanthrene and Pb in ryegrass, and the residual concentrations of phenanthrene and Pb in soils significantly decreased. Under the co-contamination of 500 mg Pb kg −1 and 50 mg PHE kg −1 , the bioconcentration factor of phenanthrene and Pb in the presence of CCD was increased by 1.43-fold and 4.47-fold, respectively. After CCD was added to the contaminated soils, the residual concentration of phenanthrene and Pb in unplanted soil was decreased by 18 and 25 %, respectively. However, for the planted soil, the residual concentration of phenanthrene and Pb was decreased by 48 and 56 %, respectively. CCD may improve the bioavailability of phenanthrene and Pb in co-contaminated soil; CCD enhanced phytoremediation technology may be a good alternative for the removal of hydrophobic organic contaminants and heavy metals from contaminated soils.
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PubMed
高影响因子
IRANIAN POLYMER JOURNAL
·
2015
·Vol. 24
·期 3
·219-227
·
IF 1.806
Lü Ting,Liu Xingyuan,Qi Dongming,Zhao Hongting
Aqueous dispersion polymerization has been considered as a promising green technology for preparing water-soluble polymers such as cationic polyacrylamide (CPAM). Dispersion copolymerization of acrylamide and 2-methylacryloylxyethyl trimethyl ammonium chloride was generally carried out in aqueous ammonium sulfate solution with poly(2-methylacryloylxyethyl trimethyl ammonium chloride) as the stabilizer. In this study, we reported the potential influence of a small amount of hydrophobic monomer, methyl methacrylate (MMA), on the above-mentioned aqueous dispersion polymerization system. It was found that MMA could play an important role in the polymerization process by significantly affecting the particle formation and stabilization, as well as the viscosity evolution of the reaction mixture during polymerization. With the addition of a small amount of MMA, the particle formation was accelerated and the viscosity of the polymerization system decreased significantly. With the increase in MMA addition, the final copolymer particle size was reduced and its size distribution became narrower; meanwhile, the particle morphology tended to be spherical. Moreover, it was found that the addition of MMA could favor the production of CPAM with high charge density. The flocculation performance of the resulting CPAM dispersion was also examined in detail and it was found that the introduction of MMA unit into CPAM molecular chain could improve its flocculation efficiency.
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高影响因子
COLLOID AND POLYMER SCIENCE
·
2015
·Vol. 294
·期 2
·441-453
·
IF 1.865
Shi Zhen-Qiang,Ji Hai-Feng,Yu Hai-Chao,Huang Xue-Lian,Zhao Wei-Feng,Sun Shu-Dong,Zhao Chang-Sheng
Hollow fiber membranes with satisfied blood compatibility and antibacterial property are desired in blood purification. Herein, a series of heparin-like copolymers of poly(methyl methacrylate-vinyl pyrrolidone -sodium styrene sulfonate-sodium acrylate) (poly(MMA-VP-SSNa-SA)) were synthesized by free radical solution polymerization. The mixture was directly blended with polyethersulfone (PES) solution to prepare hollow fiber membranes. The membranes were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Blood compatibility of the hollow fiber membranes was evaluated via protein adsorption, platelet adhesion, clotting time, and hemolysis assay. Besides, Ag nanoparticles were immobilized onto the hollow fiber membranes efficiently by a simple and green method, and the antibacterial property and blood compatibility of the Ag-loaded membranes were then investigated. The results indicated that the approach towards blood compatible and antibacterial hollow fiber membrane is efficient and flexible for the modification for membrane materials.
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高影响因子
MICROCHIMICA ACTA
·
2015
·Vol. 183
·期 2
·589-596
·
IF 3.741
Tang Yiwei,Li Min,Gao Xue,Liu Xiuying,Ma Yong,Li Yi,Xu Yongxia,Li Jianrong
Hollow molecularly imprinted polymers (h-MIPs) consisting of K 2 Ti 4 O 9 as a sacrifice matrix were synthesized for selective recognition of enrofloxacin (ENR). The h-MIPs possess a characteristic nanostructure and were characterized by Fourier transform infrared spectroscopy, X-ray powder diffraction and transmission electron microscopy. The h-MIPs have a fast adsorption kinetic (~10 min), high adsorption capacity and a good selectivity factor (2.4) for ENR. Following adsorption of ENR, it was eluted from the sorbent with methanol-acetic acid (8:2) and quantified by HPLC. The calibration plot extends from 0.5 to 16.0 ng mL‾ 1 of ENR with a correlation coefficient of 0.9912, and the limit of detection is 0.24 ng mL‾ 1 (at an S/N ratio of 3). The method was applied to the determination of ENR in spiked fish samples, and recoveries ranged from 68.88 to 100.29 % with relative standard deviations (for n = 3) between 1.6 and 4.4 %.
Hollow molecularly imprinted polymers (h-MIPs) were synthesized using K 2 Ti 4 O 9 as sacrifice matrix for selective recognition of enrofloxacin (ENR). These MIPs served as an SPE adsorbent for purification and enrichment of ENR prior to quantitation by HPLC
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高影响因子
JOURNAL OF POLYMER RESEARCH
·
2015
·Vol. 22
·期 11
·1-8
·
IF 1.92
Wei Wan-Chu,Feng Shuo,Zheng Cai-Xia,Liang Guo-Dong,Gao Hai-Yang,Wu Qing,Zhu Fang-Ming
Amphiphilic fluorescent diblock copolymers containing a pyrene-labelled polystyrene (PyPS) block, PyPS-block-poly(acrylic acid) (PyPS- b -PAA) and PyPS-block-poly(ethylene oxide) (PyPS- b -PEO) were synthesized by atom transfer radical polymerization (ATRP). All resultant diblock copolymers and intermediates were characterized by nuclear magnetic resonance (NMR) spectroscopy and gel permeation chromatography (GPC). PyPS- b -PAA in water and PyPS- b -PEO in water or ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)-imide ([EMIM][TFSI]) can self-assemble into spherical nanomicelles with diameters less than 100 nm. Glass transition and fluorescent quantum yield of the core-forming PyPS block confined in the self-assembled spherical nanomicelles were investigated by fluorescence spectroscopy. A dramatic reduction of glass transition temperature ( T
g
) of the PyPS block within PyPS- b -PEO nanomicelles was observed relative to PS or PyPS bulk. However, in aqueous dispersions, the PyPS block within PyPS- b -PAA nanomicelles exhibited an analogous T
g near to PS or PyPS bulk. Moreover, the fluorescent quantum yield of the PyPS block within the self-assembled nanomicelles in aqueous dispersions is much higher than that of PyPS- b -PEO in toluene solution as well as its bulk.
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高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2014
·Vol. 16
·期 11
·1-13
·
IF 2.278
Liu Wenjuan,Yao Jun,Cai Minmin,Chai Hankuai,Zhang Chi,Sun Jingjing,Chandankere Radhika,Masakorala Kanaji
A new nanopesticide, carboxymethyl-β-cyclodextrin-Fe 3 O 4 magnetic nanoparticles-Diuron (CM-β-CD-MNPs-Diuron), was synthesized from an inclusion complex of CM-β-CD-MNPs as host and diuron as guest molecules. The transmission electron microscopy revealed it had an average diameter of 25 nm which is more or less the same as that of MNPs (average diameter ~23 nm). The CM-β-CD grafting was confirmed by infrared spectroscopy, and the amount of CM-β-CD grafted on the surface of MNPs was determined to be 144.1 mg/g by thermogravimetry. The feasibility of using CM-β-CD-MNPs as a nanocarrier for loading diuron was verified by investigating the formation of inclusion complex. The complexation of CM-β-CD-MNPs with diuron followed the Langmuir adsorption isotherm. In this work, the potential toxic effect of CM-β-CD-MNPs-Diuron on soil microbial was evaluated by microcalorimetry, urease enzyme and real-time quantitative PCR (qPCR). The thermokinetic parameters were observed to decrease with increase in the loading of CM-β-CD-MNPs-Diuron in soil. The urease activity data showed that there was a significant effect ( p < 0.05) of CM-β-CD-MNPs-Diuron on the enzyme activity. The microcalorimetric analysis was in agreement with qPCR, confirming the toxic effect of this nanopesticide on microorganism in soil.
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高影响因子
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
·
2014
·Vol. 29
·期 5
·1090-1097
·
IF 0.422
Tang Yimei,Hu Xiaoling,Guan Ping,Li Xiaoqian,Tian Tian
Several 1-vinyl-3-alkylimidazolium halogens [VRIM]X, which are functional materials with ethylenic bonds, were synthesized using the microwave-assisted synthesis method. Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy were carried out to analyze the resultant structures. The electrochemical properties and solubility of [VRIM]Br were investigated and discussed in detail. The temperature dependence of pure [VRIM]Br over a wide temperature range of 298.15–323.15 K fitted the Arrhenius equation well. At certain low concentrations, the electrical conductivity of the [VRIM]Br solution significantly increased with increasing solution concentration. The electrical conductivities of the [VRIM]Br observed in water, methanol, and ethanol showed the trend σ
water > σ
methanol > σ
ethanol . Conductometry showed that the critical micelle concentrations of the bromines in water, methanol, and ethanol were 6.8–6.9 × 10 −6 , 1.4–1.5 × 10 −5 , and 1.9–2.0×10 −5 mol·L −1 , respectively; these results indicate that [VRIM]Br is an excellent surfactant. The solubility of [VRIM]X in common solvents was determined at 293.15 K, and results indicated that a decrease in solubility could be observed with decreasing dielectric constant of the solvent, elongation of the alkyl chain of the cation, and increasing anion size. Solubility parameters were also determined according to the Hildebrand-Scoff equation.
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高影响因子
MICROCHIMICA ACTA
·
2014
·Vol. 182
·期 3
·687-693
·
IF 3.719
Tian Li,Wang Binbin,Chen Ruizhan,Gao Ye,Chen Yanling,Li Tianjiao
A glassy carbon electrode (GCE) was modified with a film containing titanium dioxide and a Pt(II)-porphyrin complex, and its response to quercetin was investigated employing cyclic voltammetry and chronoamperometry. The oxidation current caused by quercetin is largely enhanced under UV illumination. The effects of pH value, mass of TiO 2 in the film, UV illumination time and applied potential were studied. Under optimized conditions, the peak current at a typically applied voltage of +0.4 V depends linearly on the concentration of quercetin in the 0.002 to 50 mg L −1 range. The detection limit (at an SNR of 3) is 0.8 μg L −1 . The method was successfully applied to the determination of quercetin in (spiked) samples of tea and apple juice.
Figure Cyclic voltammograms of the TiO 2 /PtP/GCE in the absence and presence of various concentrations of quercetin in 0.1 M NaOH. a-e: 0, 0.1, 0.2, 0.3 and 0.4 mg L -1 .
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高影响因子
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