BIOLOGICAL TRACE ELEMENT RESEARCH
·
2013
·Vol. 154
·期 1
·156-166
·
IF 1.307
Chen Shizhu,Hou Yingjian,Cheng Gong,Zhang Cuimiao,Wang Shuxiang,Zhang Jinchao
Oxidative stress is well documented to cause injury to endothelial cells (ECs), which in turn trigger cardiovascular diseases. Previous studies revealed that cerium oxide nanoparticles (nanoceria) had antioxidant property, but the protective effect of nanoceria on ROS injury to ECs and cardiovascular diseases has not been reported. In the current study, we investigated the protective effect and underlying mechanisms of nanoceria on oxidative injury to ECs. The cell viability, lactate dehydrogenase release, cellular uptake, intracellular localization and reactive oxygen species (ROS) levels, endocytosis mechanism, cell apoptosis, and mitochondrial membrane potential were performed. The results indicated that nanoceria had no cytotoxicity on ECs but had the ability to prevent injury by H 2 O 2 . Nanoceria could be uptaken into ECs through caveolae- and clathrin-mediated endocytosis and distributed throughout the cytoplasma. The internalized nanoceria effectively attenuated ROS overproduction induced by H 2 O 2 . Apoptosis was also alleviated greatly by nanoceria pretreatment. These results may be helpful for more rational application of nanoceria in biomedical fields in the future.
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PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2013
·Vol. 405
·期 17
·5843-5852
·
IF 3.659
Wen Yingying,Li Jinhua,Liu Junshen,Lu Wenhui,Ma Jiping,Chen Lingxin
A dual cloud point extraction (dCPE) off-line enrichment procedure coupled with a hydrodynamic–electrokinetic two-step injection online enrichment technique was successfully developed for simultaneous preconcentration of trace phenolic estrogens (hexestrol, dienestrol, and diethylstilbestrol) in water samples followed by micellar electrokinetic chromatography (MEKC) analysis. Several parameters affecting the extraction and online injection conditions were optimized. Under optimal dCPE–two-step injection–MEKC conditions, detection limits of 7.9–8.9 ng/mL and good linearity in the range from 0.05 to 5 μg/mL with correlation coefficients R
2 ≥ 0.9990 were achieved. Satisfactory recoveries ranging from 83 to 108 % were obtained with lake and tap water spiked at 0.1 and 0.5 μg/mL, respectively, with relative standard deviations ( n = 6) of 1.3–3.1 %. This method was demonstrated to be convenient, rapid, cost-effective, and environmentally benign, and could be used as an alternative to existing methods for analyzing trace residues of phenolic estrogens in water samples.
A dual cloud point extraction (dCPE) off-line enrichment procedure coupled with a hydrodynamic–electrokinetic two-step injection online enrichment technique was successfully developed for simultaneous preconcentration of trace phenolic estrogens in water samples followed by MEKC analysis.
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PubMed
高影响因子
Journal of Coatings Technology and Research
·
2013
·Vol. 10
·期 5
·621-629
·
IF 1.094
Xiong Jinsu,Jin Yunquan,Shentu Baoqing,Weng Zhixue
Poly[1,2-propylene glycol-3-(2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptoxy)]phthalate (PDFP) was prepared by the reaction of phthalic anhydride, epichlorohydrin, and 2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl glycidyl ether (DFGE). The structure of PDFP was characterized with 1 H-NMR, 19 F-NMR, FTIR and the wettability of water and oil on cured PDFP coatings was investigated by contact angle meter. The results showed that the contact angle of water and diiodomethane on cured coatings increased with the increase of the fluorine content and could maximally attain 108° and 69°, respectively. At a fluorine content of 0.75%, the surface energy was 21.1 mJ/m 2 . X-ray photoelectron spectroscopic (XPS) analysis showed that the surface F/C atomic ratio was much higher than the overall F/C molar ratio, indicating that the fluoroalkyl groups in PDFP had enriched on the coating surface. It was also found that the fluorinated polyester with longer fluoroalkyl groups had the higher tendency to enrich on the coating surface.
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高影响因子
MICROCHIMICA ACTA
·
2014
·Vol. 182
·期 1
·201-208
·
IF 3.719
Luo Jinmei,Zhang Jiahui,Lin Jianxing,Wang Jinhui,Yang Peihui
We report on a simple and rapid method for the enrichment of polyphenolic compounds (pPhCs) by means of gold nanorods whose surface was functionalized with a monolayer of β-cyclodextrin (β-CD-AuNRs) via thiol chemistry. Enrichment is based on the formation of inclusion complexes between pPhCs and β-cyclodextrin through hydrophobic interactions and hydrogen bonding. Fourier transform infrared spectroscopy, mass spectrometry, and transmission electron microscopy were applied to confirm the inclusion of the pPhCs. Moreover, binding leads to a quenching of the red fluorescence of the AuNRs. This effect can be applied to quantify the polyphenols mangiferin, chrysin, and daphnetin with detection limits at 5 nM, 15 nM, and 20 nM concentrations, respectively. Water samples were spiked with pPhCs, and their extraction by using β-CD-AuNRs gave recoveries ranging from 97.6 to 110.2 %.
Gold nanorods were functionalized with β-cyclodextrin via thiol chemistry. Based on the formation of inclusion complexes between polyphenolic compounds (pPhCs) and β-cyclodextrin through hydrophobic interactions and hydrogen bonding, β-cyclodextrin functionalized gold nanorods as fluorescent probe to simple, rapid and quantitative detect polyphenolic compounds
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高影响因子
FIBERS AND POLYMERS
·
2014
·Vol. 15
·期 7
·1364-1368
·
IF 1.113
Chen Zaina,Feng Xiaoxiao,Han Danmin,Wang Liting,Cao Weipen,Shao Linjun
Porous polyacrylonitrile (PAN) fiber mat was prepared by electrospinning PAN in N,N -dimethylformide solution with poly(methyl methacrylate) (PMMA) as pore-forming agent. Then, the porous PAN fiber mat was chemical modified by the tetraethylenepentamine to acquire aminated porous polyacrylonitrile (APPAN) fiber mat. Common aminated PAN fiber mat was also prepared for comparison. The surface morphologies of the APPAN and PAN fiber mat were characterized by scanning electron microscopy (SEM) and the corresponding specific surface areas were also measured. FT-IR/ATR spectra of the APPAN and PAN fiber mat were recorded for analysis of the surface chemical structures. The Cr(VI) absorption results demonstrated that the porous structure in the fiber could obviously increase the absorption capacity of the fiber mat.
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高影响因子
Journal of Central South University
·
2014
·Vol. 21
·期 7
·2645-2651
·
IF 0.464
Zhao Jin-yao,Li Li,Jiao Fei-peng,Ren Feng-lian
The human plasma protein binding of water soluble flavonoids in the peels of five spices of citrus fruits was studied by ultrafiltration combined with HPLC. The flavonoids were extracted separately by hot and cold water, and higher total flavonoid contents were detected in the former extracts than the latter ones. All the extracts show significant scavenging abilities to both ABTS and DPPH free radicals, which indicates the health benefits of the water extracts of citrus fruits peels. For DPPH radical, the IC 50 values of hot extract follow as Navel orange (NO)≈Mandarin orange (MO)< Lemon (LE)< Lo tangerine (LO)< Pomelo (PO), while the rank is NO< PO
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高影响因子
Food Analytical Methods
·
2014
·Vol. 8
·期 2
·428-437
·
IF 1.802
Zeng Fang,Ou Jun,Huang Yufen,Li Qian,Xu Guizhi,Liu Zhongzhen,Yang Shaohai
The present paper reports the application of an optimized pre-column derivatization procedure with aminoquinolyl- N -hydroxysuccinimidyl carbamate (AQC) to the determination of 21 free amino acids in fruit juices. The method permitted the optimal separation of 21 amino acids and ammonium in 30 min. Excellent response linearity was obtained from 2 to 1,000 μM for all amino acids, except tryptophan, for which the linearity was 5–1,000 μM. The fluorescence detection limits ranged from 0.08 pmol (phenylalanine) to 0.69 pmol (cysteine), except for tryptophan (7.89 pmol), for a signal-to-noise ratio of 3. The relative standard deviations of peak areas ranged from 0.1 to 0.4 % for intraday analysis and from 2.1 to 5.0 % for interday analysis. The method was applied to analyze the free amino acids in six fruit juices, and the recoveries of the proposed method were 90.4 to 103.3 %. The total free amino acid content ranged from 56.97 mg L −1 (apple) to 469.45 mg L −1 (longan) in six fruit juices. Aspartic acid (Asp), glutamic acid (Glu), asparagine (Asn), serine (Ser), and glutamine (Gln) were present in higher levels in most samples, whereas cysteine (Cys) was below the detection limit in the selected samples. Notable advantages of this method include its speed, ease, low cost, good repeatability, high sensitivity, excellent precision and accuracy, and anti-interference in high-sugar matrices.
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高影响因子
MICROCHIMICA ACTA
·
2014
·Vol. 181
·期 13
·1591-1599
·
IF 3.719
Ban Rui,Zhu Jun-jie,Zhang Jianrong
We present a sensitive and selective method for the determination of organophosphorus pesticides (OPs) based on the inhibition of the enzyme acetylcholinesterase (AChE). It is making use of quantum dots QDs of the type Mn: ZnS that display long-lived phosphorescence emission and act as optical probes for hydrogen peroxide (H 2 O 2 ). In this assay, acetylcholine (ACh) is first hydrolyzed by AChE, and the enzyme choline oxidase (ChOx) further oxidizes choline under the formation of H 2 O 2 which quenches the phosphorescence of the QDs. If, however, OPs are added to the solution, the rate of enzymatic hydrolysis by AChE is retarded. This reduces the rate of production of H 2 O 2 and results in a reduced quenching efficiency. The slow decay time of the phosphorescence of the QDs also allows time-resolved luminescence intensity to be measured. This can eliminate background fluorescence from the sample and therefore improves analytical accuracy and the signal-to-noise ratio. Under optimized conditions, there is a linear relationship between luminescence intensity and the concentration of paraoxon in the 1 pM to 1 μM range, with an ~0.1 pM limit of detection which is much lower than that of most existing methods. The phosphorescent probe was applied to determine OPs in spiked real samples.
We present a sensitive and selective method for the determination of organophosphorus pesticides (OPs) based on the inhibition of the enzyme acetylcholinesterase (AChE). It is making use of quantum dots QDs of the type Mn-doped ZnS that display long-lived phosphorescence emission and act as optical probes for hydrogen peroxide (H 2 O 2 ).
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高影响因子
BIOLOGY AND FERTILITY OF SOILS
·
2015
·Vol. 52
·期 1
·65-76
·
IF 3.398
Zhao Hai-Ming,Du Huan,Feng Nai-Xian,Xiang Lei,Li Yan-Wen,Li Hui,Cai Quan-Ying,Mo Ce-Hui
A novel 2D strain that could effectively degrade di- n -butylphthalate (DBP) and its major metabolite, phthalic acid (PA), was isolated from compost and identified as Providencia sp . 2D. A complete degradation of DBP (200 mg L −1 ) was observed within 3 days under optimal conditions obtained by response surface methodology. This strain 2D could utilize various phthalic acid esters (PAEs) as substrates for growth, and could co-metabolize DBP in the presence of extra C sources. A novel combination of two common pathways in PA degradation was proposed for DBP degradation pathway, representing the first report of two ring cleavage pathways of the intermediate PA in a microbial species. Strain 2D efficiently enhanced the removal rate of DBP in contaminated soil with a sharp decrease of the DBP half-life compared to non-bioaugmentation treatments. Moreover, the addition of compost improved the degradation rate of DBP in soil by stimulating microbial activity. The results support the feasibility of remediating DBP-contaminated soils inoculated with strain 2D and treated with compost.
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高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
·
2015
·Vol. 20
·期 1
·1-8
·
IF 2.446
Zhong Haoxiang,Sun Minghao,Li Yong,He Jiarong,Yang Jianwen,Zhang Lingzhi
The polyacrylic latex (LA132) was firstly reported as a water-soluble binder for LiNi 1/3 Co 1/3 Mn 1/3 O 2 (NCM) cathode in Li-ion battery. The electrochemical performances of NCM cathode with LA132 binder were investigated and compared with the conventional water-soluble sodium carboxymethyl cellulose (CMC) and commercial non-aqueous polyvinylidene difluoride (PVDF). NCM cathode with LA132 binder exhibited a much higher specific capacity of 146 mAh g −1 and capacity retention of 96.4 % after 100 cycles as compared with 122 mAh g −1 /88 % and 121 mAh g −1 /75% for the NCM electrode with CMC and PVDF, respectively. In addition, NCM cathode with LA132 binder exhibited better rate capability than that of CMC and PVDF, e.g., retaining 34.3 % capacity of C/5 at 5 C rate as compared with 28.5 and 10.9 % for CMC and PVDF, respectively.
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高影响因子
MICROCHIMICA ACTA
·
2014
·Vol. 182
·期 3
·737-744
·
IF 3.719
Yang Jing,Si Ling,Cui Shihai,Bi Wentao
We have developed a facile in-situ growth method for the deposition of magnetite (Fe 3 O 4 ) particles on the surface of a graphitic carbon nitride (g-C 3 N 4 ) nanosheet. The material was characterized by X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The high affinity of g-C 3 N 4 for phenolic acids in combination with the magnetism of Fe 3 O 4 provides an efficient means for magnetic solid phase extraction. The adsorption, desorption and recoveries were examined. Under optimized conditions, the method has limits of detection in the range from 17.5–42.6 ng mL −1 (at an S/N of 3), and precisions from 2.8–3.8 % (for n = 5). The method was successfully applied to the determination of protocatechuic, caffeic, and ferulic acids in Salicornia herbacea L . plant extracts. Recoveries ranged from 92.4–99.5 %.
The high affinity of g-C 3 N 4 toward the phenolic acids as well as the magnetic behavior of Fe 3 O 4 were combined in this nanocomposite material to provide an efficient and simple magnetic solid phase extraction (MSPE) approach.
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高影响因子
MICROCHIMICA ACTA
·
2014
·Vol. 182
·期 3
·679-685
·
IF 3.719
Xu Guiyun,Wang Wenting,Li Beibei,Luo Zhonglin,Luo Xiliang
An electrochemical dopamine sensor was developed by electrochemical modification of a carbon paste electrode with a biocomposite made from poly(3,4-ethylenedioxythiophene) (PEDOT) that was doped with double stranded or single stranded DNA. The resulting conducting biocomposite displays excellent electrocatalytic activity towards the oxidation of dopamine (DA) which is attributed to the presence of the DNA dopant. Under optimum conditions and at a working potential of 300 mV, the modified electrode is capable of detecting DA in the 0.25 to 66 μM concentration range. The detection limit is 74 nM. The sensor is not interfered by uric acid and ascorbic acid.
PEDOT biocomposites doped with dsDNA (left) and ssDNA (right) can be electrochemically prepared and used for the sensitive and selective detection of dopamine owing to their excellent catalytic activity towards dopamine oxidation.
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高影响因子
危险品化学品经营许可证（带存储）