EUROPEAN FOOD RESEARCH AND TECHNOLOGY
·
2014
·Vol. 238
·期 5
·889-894
·
IF 1.387
Zhu Jinghui,Li Chunyan,Liu Shaopu,Liu Zhongfang,Yang Jidong,Tian Jing,Hu Xiaoli
A non-diazotization-coupling reaction-based colorimetric method was developed and validated for the determination of nitrite in tap water and milk samples. Under acidic condition, nitrite could selectively react with pyrrole, resulting in the emerging of a new absorption peak at 509 nm and a distinct color change from clear to red, with which the concentration of nitrite can be determined indirectly. Excellent linear range was achieved from 0.72 to 40.0 μmol L −1 with a detection limit of 0.22 μmol L −1 . The detection limit was lower than or comparable to most of the recently published methods. The experimental conditions were optimized, and effects of coexisting substances were evaluated, and the results showed excellent priority since a certain amount of other anions, including SO 3
− , SeO 3
− and other acid radicals, would not interfere with the measurement. We highlighted the simplicity and efficiency of this method as no diazotization-coupling procedure and toxic aniline were involved. Determination of nitrite in tap water and milk samples was performed.
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CHINESE JOURNAL OF POLYMER SCIENCE
·
2014
·Vol. 32
·期 5
·540-550
·
IF 1.42
Guo Hua,Yang Cheng-ling,Wang Wei,Wu Yu-kun,Lai Quan-yong,Yuan Zhi
A series of drug delivery systems based on a sodium alginate derivative were prepared by mixing glycyrrhetinic acid (GA) and doxorubicin (DOX) conjugates at different ratios. GA (a liver-targeting ligand) and DOX (an antitumor drug) were both conjugated to oligomeric glycol monomethyl ether-modified sodium alginate (ALG-mOEG) for prolonged duration of action. These NP-based delivery systems exhibited active cell uptake and cytotoxicity in vitro and liver-targeted distribution and anti-tumor activity in vivo . In addition, nanoparticles with a 1:1 ( W : W ) ratio of GA-ALG-mOEG and DOXALG-mOEG (NPs-3) showed the highest cellular uptake and cytotoxicity in vitro and liver-targeted distribution and antitumor activity in vivo . Specifically, when mixed nanoparticles defined as NPs-3 were injected in mice, liver DOX concentration reached 61.9 μg/g 3 h after injection, and AUC 0-∞ and t
1/2 of DOX in liver reached 4744.9 μg·h/g and 49.5 h, respectively. In addition, mice receiving a single injection of NPs-3 exhibited much slower tumor growth (88.37% reduction in tumor weight) 16 days after injection compared with placebo. These results indicate that effective cancer treatment may be developed using mixed NP delivery systems with appropriate ratio of targeted ligand and drug.
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JOURNAL OF SOLUTION CHEMISTRY
·
2013
·Vol. 42
·期 10
·1879-1887
·
IF 1.128
Guo Song,Yang Wenge,Hu Yonghong,Wang Kai,Luan Yuanyuan
The solubility of N -acetylglycine was measured in methanol, ethanol, propanol, isopropanol, n -butanol and ethyl formate in the temperature range between 278.15 and 319.15 K under atmospheric pressure by a gravimetric method. The solubility of N -acetylglycine in those selected solvents increases with increasing temperature. The solubility data were correlated with the van’t Hoff equation, the modified Apelblat equation and the λh equation to obtain the corresponding model parameters. The experimental results could be useful for optimizing the industrial process of purification of N -acetylglycine.
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PHARMACEUTICAL RESEARCH
·
2013
·Vol. 31
·期 2
·291-304
·
IF 4.742
Yang Xiao-Li,Luo Yan-Ling,Xu Feng,Chen Ya-Shao
Purpose Block copolymer micelles are extensively used as drug controlled release carriers, showing promising application prospects. The comb or brush copolymers are especially of great interest, whose densely-grafted side chains may be important for tuning the physicochemical properties and conformation in selective solvents, even in vitro drug release. The purpose of this work was to synthesize novel block copolymer combs via atom transfer radical polymerization, to evaluate its physicochemical features in solution, to improve drug release behavior and to enhance the bioavailablity, and to decrease cytotoxicity. Methods The physicochemical properties of the copolymer micelles were examined by modulating the composition and the molecular weights of the building blocks. A dialysis method was used to load hydrophobic camptothecin (CPT), and the CPT release and stability were detected by UV–vis spectroscopy and high-performance liquid chromatography, and the cytotoxicity was evaluated by MTT assays. Results The copolymers could self-assemble into well-defined spherical core-shell micelle aggregates in aqueous solution, and showed thermo-induced micellization behavior, and the critical micelle concentration was 2.96–27.64 mg L −1 . The micelles were narrow-size-distribution, with hydrodynamic diameters about 128–193 nm, depending on the chain length of methoxy polyethylene glycol (mPEG) blocks and poly(N-isopropylacrylamide) (PNIPAM) graft chains or/and compositional ratios of mPEG to PNIPAM. The copolymer micelles could stably and effectively load CPT but avoid toxicity and side-effects, and exhibited thermo-dependent controlled and targeted drug release behavior. Conclusions The copolymer micelles were safe, stable and effective, and could potentially be employed as CPT controlled release carriers.
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PubMed
高影响因子
Science China-Chemistry
·
2013
·Vol. 56
·期 11
·1641-1650
·
IF 1.327
Qing XiangDong,Wu HaiLong,Nie ChongChong,Li Yong,Yan XiuFang,Zhang XiHua,Yin XiaoLi,Yu RuQin
This work presents a novel application of second-order calibration based on self-weighted alternating trilinear decomposition (SWATLD) algorithm for analyzing the HPLC-DAD data. The proposed method makes it possible to simultaneously determine teflubenzuron, hexaflumuron, flufenoxuron, chlorfluazuron, diflubenzuron and benzoylurea in different fruit samples, i.e. pear, apple and banana, in the selected time region of chromatogram. The concentration, elution time and spectral information of these benzoylurea insecticides are selectively extracted from complex matrices even in the presence of unknown interferences. The root-mean-square error of prediction (RMSEP) and figures of merit, including sensitivity (SEN), selectivity (SEL) and limit of detection (LOD) are employed to access the performance of the method. The LODs obtained for these insecticides are within the range 0.017–0.26 ppm in pears, 0.039–0.33 ppm in apples, 0.041–0.44 ppm in bananas, respectively. Such a chemometrics-based protocol holds great potential to be extended as a promising alternative for more practical applications in food safety and quality monitoring.
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CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2015
·Vol. 31
·期 5
·730-735
·
IF 0.875
Xu Panpan,Wang Chunfeng,Sun Dong,Chen Yujuan,Zhuo Kelei
A facile approach was reported for the synthesis of nitrogen- and sulfur-co-doped carbon dots(N/S-CDs) by the sulfuric acid carbonization of 1-butyl-3-methylimidazolium 2-amino-3-mercaptopropionic acid( L -cysteine) salt([C 4 mim][Cys]) ionic liquid. The as-prepared N/S-CDs exhibited a good solubility, excitation-dependent emission behavior, and high resistance to photobleaching. Furthermore, the N/S-CDs were employed as a fluorescent probe for detecting Cu 2+ in real water samples with satisfactory recovery.
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MICROCHIMICA ACTA
·
2015
·Vol. 182
·期 13
·2313-2320
·
IF 3.741
Xu Yan,Jin Jingjie,Li Xianliang,Han Yide,Meng Hao,Song Chaosheng,Zhang Xia
We describe a facile method for the preparation of magnetic microparticles consisting of a metal-organic framework (MOF) of Cu(II)-BTC (BTC = 1,3,5-benzenetricarboxylate) for rapid magnetic solid-phase extraction (MSPE) of the dye Congo Red (CR) from aqueous solution. Magnetization of the MOF and solid-phase extraction of CR was simultaneously accomplished by mixing, under ultrasonication, the MOF and silica-coated magnetite microparticles in the solution to be extracted. Under optimized conditions, the magnetic MOF hybrid exhibits a fast adsorption rate and a high removal efficiency (>97 %) toward CR even over 15-fold reuse, which also features high adsorption capacity of 97.7 and 92.5 % for cationinc Methylene Blue (MB) and Crystal Violet (CV), respectively. The desorption of CR from the magnetic MOF was realized by washing it with ethanol and water. The material is considered to be a promising new adsorbent for use in wastewater treatment and in analytical preconcentration.
We report on a method for magnetization of a Cu-BTC metal-organic framework for use in rapid magnetic solid phase extraction of Congo Red from aqueous solutions. The material maintains its high removal efficiency (of >97 %) over 15 recyclable experiments.
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APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2015
·Vol. 120
·期 4
·1291-1297
·
IF 1.704
Wang Xinyu,Ying Yulong,Hu Pan,Lei Jiahuan,Peng Xinsheng
CdS nanowires (NWs) are obtained by the sulfurization of Cd(OH) 2 nanowires at room temperature using H 2 S. The CdS NWs with diameter of 2–5 nm exhibit high photocatalytic performance due to the ultrafine size. To further improve the performance, Au nanoparticles (NPs) with different sizes, i.e., 5, 20, 40 and 100 nm, that decorated the CdS NWs are synthesized through a simple self-assembly and solid sulfuration process. The synthesized Au NPs–CdS NWs hybrids show higher photocatalytic efficiency than that of pure CdS NWs. Furthermore, 20 nm Au NPs–CdS NWs hybrids with an optimal Au loading of 3.2 wt% exhibit the highest photocatalytic efficiency. Both the enhanced separation of photoinduced hole–electron pairs and the absorption of visible light by incorporating Au NPs significantly improve the photocatalytic performance.
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JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2015
·Vol. 76
·期 3
·651-657
·
IF 1.532
Guo Xingzhong,Hao Guisong,Xie Yuan,Cai Weiwei,Yang Hui
Abstract Porous zirconia (ZrO 2 ) microspheres with incontinuous multicavities were prepared via emulsion method combined with phase separation in the presence of polyvinylpyrrolidone (PVP). The morphology of the microspheres is derived from the spherical oil droplets by high-speed shearing and the sol–gel reaction on the droplets, while the PVP acts as a phase separation inducer to form incontinuous multicavities inside the microspheres. The addition of PVP does not change the particle size distribution and smooth surface morphology of the microspheres, while the size of cavities inside microspheres increases gradually with the increase in PVP amount. The particle characteristics, phase transformation and cavity formation mechanism of porous ZrO 2 microspheres are analyzed in detail. Graphical Abstract Porous ZrO 2 microspheres with incontinuous multicavities were prepared via emulsion method combined with phase separation in the presence of polyvinylpyrrolidone (PVP). The morphology of the microspheres is derived from the spherical oil droplets by high-speed shearing and the sol–gel reaction on the droplets, while the PVP acts as a phase separation inducer to form incontinuous multicavities inside the microspheres. A schematic illustration of the formation mechanism of ZrO 2 microspheres with PVP and without PVP
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IRANIAN POLYMER JOURNAL
·
2015
·Vol. 24
·期 9
·747-758
·
IF 1.806
Gao Xin,Chen Keli,Zhang Heng,Yan Xuejing
A rapid microwave-assisted cationic synthesis of cellulosic polymer by grafting glycidyl trimethyl ammonium chloride (GTMAC) onto parenchyma cellulose (PC) from bagasse pith under low-power condition is reported. The effects of the microwave power, exposure time, GTMAC charge, water content, and aqueous-organic solvents by volume ratio were evaluated by determining cationization parameters such as yield, degree of substitution (DS), zeta potential, and charge density. The experimental results showed that the water-soluble and -insoluble fractions of cationic parenchyma cellulose (CPC) were obtained and their optimal DS were determined to be 0.72 and 0.63 at the microwave power of 100 W for 20 min, respectively. Surface cationization of PC resulted in an increase in zeta potential and charge density over the unmodified cellulose. In comparison with the original PC, the intrinsic viscosity of the cationic products decreased significantly. The presence of GTMAC on the surface of PC was confirmed by Fourier transform infrared spectroscopy. The crystallinity and surface structure of original cellulose and CPCs were also analyzed through X-ray diffraction and scanning electron microscopy, respectively. This work provided an efficient and economical feasibility to produce a cationic biopolymer from cellulose.
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JOURNAL OF MATERIALS SCIENCE
·
2015
·Vol. 50
·期 12
·4405-4411
·
IF 2.371
Yang Jinyu,Jia Xiaohui,Zeng Xiaodao,Zhu Liping,Chen Zhuo
Pure phase of LaP 3 O 9 Eu 3+ phosphors with orthorhombic structure was successfully synthesized by a polyacrylamide gel process. The crystal structure, thermal behavior, and optical properties of the as-synthesized samples were investigated by XRD, TG-DTA, FT-IR, and PL. The effects of some synthesis conditions on the structure and properties of samples were also discussed. The results reveal that the annealing temperature and the ratio of (La+Eu) to P in precursor solutions play a key role in determining the structure and luminescence properties of products. The single-phase orthorhombic structure LaP 3 O 9 :Eu 3+ phosphors can be obtained by annealing at 750–850 °C. The LaP 3 O 9 :Eu 3+ phosphors emit a dominating and intense line at 618 nm, and exhibit improved photoluminescence properties compared with the samples of LaPO 4 :Eu 3+ crystals. The concentration quenching effect can be observed with increasing Eu 3+ concentration over 40 at.%.
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WATER AIR AND SOIL POLLUTION
·
2013
·Vol. 224
·期 7
·1-10
·
IF 1.748
Liu Fahui,Wang Chuanhua,Liu Xiaoyan,Liang Xia,Wang Qian
This research evaluated the effects of alkyl polyglucoside (APG), an environment-friendly surfactant, on the removal of anthracene (ANT), phenanthrene (PHE), and pyrene (PYR) from the soil cultivated with Scirpus triqueter , an aquatic native pioneer plant in the Yangtze estuarine wetland, China. Soils spiked with about 200 mg kg −1 of ANT, PHE, and PYR were individually irrigated with 0, 10, 20, 30, 40, 50, 100, and 150 mg L −1 of APG. Plant biomass yields, polycyclic aromatic hydrocarbons (PAHs) removal rates, soil microbial, and soil enzyme activities were quantified after 90 days’ cultivation of Scirpus triqueter . Experiments demonstrated that APG has an ability to facilitate PAHs degradation at appropriate concentrations. The highest removal rate of the PAHs was observed in 40 mg L −1 APG treatment, and the removal rates increased 23, 54, and 52 %, respectively, compared to the non-amended control pots. However, the PAHs removal rate decreased to a certain extent when high concentrations of APG were added. The effect on PAHs removal in the soil could be explained by the changed levels of plant biomass, soil microbial populations, and soil enzymatic activity affected by the APG. The results suggested that the use of Scirpus triqueter combined with APG was an effective means for the phytoremediation of the PAH-contaminated soil. At the same time, APG’s optimal concentration should be determined before the application in the PAH-contaminated wetlands.
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