Acta Geochimica
·
2017
·Vol. 36
·期 3
·421-425
·
IF 0
Wu Guangliang,Zhu Jian-Ming,Tan Decan,Han Guilin,Zhang Lixing,Ren Kun
Lead (Pb) isotopes have been extensively employed in tracing sources of Pb and its transport pathways through the environment. However, Pb isotopic ratios in related geochemical reference materials are scarce. Here, we report high-precision Pb isotopic ratios measured by Nu Plasma II MC-ICP-MS using calibrated 205 Tl/ 203 Tl = 2.38865 (NIST SRM 997) for mass discrimination correction. The long-term external precision (2SD) for NIST SRM 981 of Pb, BCR-2, and BHVO-2 are 0.31‰ (n = 105), 0.42‰ (n = 11), and 0.25‰ (n = 5) for 208 Pb/ 206 Pb and 0.16‰, 0.53‰, and 0.07‰ for 206 Pb/ 207 Pb, both respectively, and their Pb isotopic ratios are in excellent agreement with the recommended values. Using this method, we report for the first time Pb isotopic compositions in shale SGR-1b (USGS); coal CLB-1 (USGS); stream sediments GSD-17, -21, and -23 (IGGE); soils GSS-12, -13, -14, -15, and -16 (IGGE); plants GSV-1, -2, and -3 (IGGE); and human hair GSH-1(IGGE).
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ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2017
·Vol. 409
·期 17
·4139-4147
·
IF 3.431
Luo Yiheng,Dou Wenchao,Zhao Guangying
In this article, a facile and sensitive electrochemical method for quantification of Salmonella Pullorum and Salmonella Gallinarum ( S. Pullorum and S. Gallinarum) was established by monitoring glucose consumption with a personal glucose meter (PGM). Antibody-functionalized magnetic nanoparticles (IgG-MNPs) were used to capture and enrich S. Pullorum and S. Gallinarum, and IgG-MNPs- S. Pullorum and IgG-MNPs- S. Gallinarum complexes were magnetically separated from a sample using a permanent magnet. The trace tag was prepared by loading polyclonal antibodies and high-content glucose oxidase on amino-functionalized silica nanoparticles (IgG-SiNPs-GOx). With a sandwich-type immunoassay format, IgG-SiNPs-GOx were added into the above mixture solution and conjugated to the complexes, forming sandwich composites IgG-MNPs/ S. Pullorum and S. Gallinarum/IgG-SiNPs-GOx. The above sandwich composites were dispersed in glucose solution. Before and after the hydrolysis of glucose, the concentration of glucose was measured using PGM. Under optimal conditions, a linear relationship between the decrease of glucose concentration and the logarithm of S. Pullorum and S. Gallinarum concentration was obtained in the concentration range from 1.27 × 10 2 to 1.27 × 10 5 CFU mL −1 , with a detection limit of 7.2 × 10 1 CFU mL −1 (S/ N = 3). This study provides a portable, low-cost, and quantitative analytical method for bacteria detection; thus, it has a great potential in the prevention of disease caused by S. Pullorum and S. Gallinarum in poultry.
A schematic illustration of the fabrication process of IgG-SiNPs-GOD nanomaterials ( A ) and IgG-MNPs ( B ) and experimental procedure of detection of S. Pullorum and S. Gallinarum using GOD-functionalized silica nanospheres as trace tags based on PGM ( C ).
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PubMed
高影响因子
JOURNAL OF POROUS MATERIALS
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2017
·Vol. 25
·期 1
·55-62
·
IF 1.624
Ren Hongbo,Zhu Jiayi,Bi Yutie,Xu Yewei,Zhang Lin
Humidity-resistant antireflective (AR) porous films with ultralow refractive indices were prepared via an one-step sol–gel process by assembly of methylated hollow silica nanospheres (HSNs). The hydrophobicity and refractive indices of silica-based AR porous films could be varied between 66.0° and 115.0°, and between 1.08 and 1.14, respectively, by tuning the MTES/TEOS molar ratios. A possible assembly mechanism was proposed according to the microstructure of methylated HSNs and porous films. The various properties of silica-based AR porous films were investigated and the AR porous film could demonstrate a good AR capability of 97.6% and excellent humidity resistance.
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MICROCHIMICA ACTA
·
2017
·Vol. 184
·期 6
·1711-1719
·
IF 4.58
Fu Xiquan,Chu Yanxin,Zhao Kang,Li Jianguo,Deng Anping
The β-adrenergic agonist brombuterol (BB) is illicitly used as an additive in animal feed to enhance the lean meat-to-fat ratio. The authors describe an ultrasensitive lateral flow immunochromatographic assay (LFIA) based on the use of surface enhanced Raman scattering (SERS) for the determination of brombuterol in swine meat and urine samples. Flower-like gold-silver core-shell bimetallic nanoparticles (referred to as AuNF@Ag) displaying strong SERS enhancement were synthesized, characterized and used as the substrate for the preparation of the LFIA. Polyclonal antibody against brombuterol was immobilized on the surface of the AuNF@Ag particles carrying the Raman reporter 4-mercaptobenzoic acid (MBA). After performing an LFIA, the Raman scattering intensity of MBA on the test line was measured and used for quantitation of brombuterol. Figures of merit of this assay procedure include (a) duration of LFIA process of 15 min; (b) an IC 50 value (e.g. the concentration of brombuterol producing 50% of signal inhibition in standard curve) of 380 pg mL-1; and (c) a limit of detection as low as 0.5 pg mL-1. The LFIA is selective over the molecules salbutamol, ractopamine, phenylethanolamine A, isoproterenol and phenylephrine, but shows a 8.5% cross-reactivity to clenbuterol, probably due to the high structural similarity. Swine meat and urine samples spiked with different amounts of brombuterol were analyzed by this method and gave recoveries between 95.8 and 108.0%, and relative standard deviations between 2.0 and 6.3% (for n = 3).
Schematic presentation of the lateral flow immunochromatographic assay (LFIA) based on surface enhanced Raman scattering (SERS) using flower-like gold-silver core-shell nanoparticles. It is capable of detecting brombuterol in swine meat and urine samples with high sensitivity and specificity.
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高影响因子
Food Analytical Methods
·
2017
·Vol. 10
·期 9
·2964-2973
·
IF 2.038
Tang Yiwei,Li Min,Gao Ziyuan,Liu Xiuying,Gao Xue,Ma Tao,Lu Xiaonan,Li Jianrong
A novel fluorescence probe was designed and synthesized to quantify ractopamine in foods using molecularly imprinted polymer (MIP) as a specific recognition element and YF 3 :Yb 3+ , Er 3+ upconversion nanoparticles (UCNPs) as a fluorescence signaling component. The developed UCNP@MIP probe was characterized using X-ray powder diffraction, scanning electron microscopy, and thermogravimetric analysis. The fluorescence of UCNP@MIP probe was quenched specifically by ractopamine, and good linear regression ranging from 1.66 × 10 −8 to 3.3 × 10 −7 mol/L was obtained with the limit of detection of 8.6 × 10 −10 mol/L. This method was further applied to determine ractopamine in water and pork samples. Recoveries between 76.61 and 88.97% were obtained with relative standard deviation ranging from 1.15 to 2.67% ( n = 3). This UCNP@MIP probe combined high selectivity of MIP and high sensitivity of upconversion fluorophore and showed potential to determine various food chemical hazards.
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CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2017
·Vol. 33
·期 1
·70-73
·
IF 1.024
Li Bochao,Lin Xinrui,Zhang Yumin,Zhang Dawei,Xiao Yang,Lin Feng
A new series of 1-substituted phenyl-2-(1 H -1,2,4-triazol-1-yl)ethanone derivatives 3 a― 3 f was synthe-sized and their structures were characterized by IR, 1 H NMR, 13 C NMR and HRMS spectral analysis. Antimicrobial activities of the derivatives were measured against both bacteria and fungi. In vitro antifungal evaluation showed that five compounds( 3 b― 3 f) had growth inhibitory effects on the tested fungus, and three of them( 3 b, 3 c and 3 e) showed special efficacy against Gram negative bacteria.
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CHINESE JOURNAL OF POLYMER SCIENCE
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2016
·Vol. 34
·期 8
·1039-1046
·
IF 1.811
Gong Xian-jing,Shi De-an,Yang Ying-kui,Jiang Tao,Meng Yan-feng,Li Robert K. Y.,Jiang Shi-chun
Cross-linked PEG-based copolymers were obtained via synthesis of polyethylene glycol (PEG) and methoxy polyethylene glycol (MPEG) by the bridging and/or cross-linking agent of 2,4-tolylene diisocyanate (TDI) and/or hexamethylene-1,6-diisocyanate homopolymer (HDI trimer). The effects on the crystallization behaviors of the samples could be found with the changes in molecular weight of MC-PEG and molecular weight of SC-PEG in certain cross-linked density. It is revealed that the samples appear not to crystallize when the molecular weight of MC-PEG and SC-PEG are 1000 g/mol or less than that. The samples begin to crystallize when the molecular weight of either MC-PEG or SC-PEG reaches 2000 g/mol. The crystallinity of crystallized MC-PEG decreases with the increasing molecular weight of uncrystallized SC-PEG and the crystallinity of crystallized SC-PEG declines with the rise of molecular weight of uncrystallizable MC-PEG. The chains of SC-PEG ( M
n = 2000 g/mol) can fold and align easilier than those of MC-PEG ( M
n = 2000 g/mol), when the content of PEG is the same.
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高影响因子
JOURNAL OF MATERIALS SCIENCE
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2017
·Vol. 52
·期 22
·13203-13211
·
IF 2.599
Zhang Li-Ying,Zhang Yong,Guan Wei-Bao,Wang Ke-Fan,Cheng Zhen-Xiang,Wang Yuan-Xu
Perovskite solar cells single-doped with Br − or Cs + ions have been proved to be an effective approach to improve their efficiency and stability. In our work, we took advantage of co-doping with Br − and Cs + . At our studied doping levels from CH 3 NH 3 I:PbI 2 :CsBr = 1:1:0 ( x = 0) to 0.85:1:0.15 ( x = 0.15), CsBr doping does not introduce any detectable impurity, and the crystal grains grow larger with increasing CsBr doping level. Furthermore, when the CsBr doping level is less than x = 0.1, it can progressively enhance the optical absorption of the perovskite film, although the absorption begins to decrease when the doping level rises above x = 0.1. X-ray photoelectron spectroscopy measurements show that Br − has successfully replaced I − and bonds with Pb 2+ after CsBr doping. At the optimized doping level of x = 0.1, the incorporation of CsBr in the reaction system can improve the morphology of perovskite films and greatly enhance the efficiency from 9.8% for undoped sample to 13.6%, better than single Br − or Cs + doping. Our result shows that CsBr doping is an effective method to enhance the efficiency of perovskite solar cells.
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IONICS
·
2017
·Vol. 24
·期 3
·787-795
·
IF 2.062
Wang Ping,Zhang Di,Zhou Yiyang,Li Yu,Fang Huagao,Wei Haibing,Ding Yunsheng
A novel biodegradable 1,2,3-triazolium-functionalized PEG- b -PCL copolymer (TAPEC) was synthesized by the “click” coupling of methoxypolyethylene glycol azide and α-propargyl-ω-hydroxyl-poly(ε-caprolactone), followed by the quaternization of the 1,2,3-triazole moiety with iodomethane. All the intermediates and TAPEC were characterized by 1 H NMR, FT-IR, and gel permeation chromatography (GPC). Taking advantage of the characteristics of ionic liquid and block copolymer, this ion-containing diblock copolymer is expected to be used as a novel compatibilizer in mixed biopolyester for regulating the interface and crystallization behaviors. Hence, the TAPEC was evaluated as a compatibilizer and an interface emulsifier in the blends of polylactic acid (PLA) and poly(ε-caprolactone) (PCL). Non-isothermal crystallization experimental results showed that the TAPEC with the higher amount of ε-caprolactone units induces a plasticization and nucleate effect that increased the crystallization ability of the PLA phase; meanwhile, in the PCL phase, the agminated ionic cluster acting as a nucleating agent significantly increased the crystalline of PCL.
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MICROCHIMICA ACTA
·
2017
·Vol. 184
·期 4
·1085-1092
·
IF 4.58
You Hongjie,Hua Xiude,Feng Lu,Sun Nana,Rui Qi,Wang Limin,Wang Minghua
The authors describe a sensitive and rapid upconversion fluorescence based immunoassay for the neonicotinoid insecticide imidaclothiz (IMI). Upconversion nanoparticles (UCNPs) consisting of hexagonal phase NaYF 4 :Yb,Er were functionalized with amino groups and coupled to antibody against IMI. Gold nanoparticles (AuNPs) were used to label the antigen (analyte). Competitive binding of IMI and AuNPs-labeled IMI to the UCNPs-labeled antibody results in a change in the fluorescence of the UCNPs at excitation/emission wavelengths of 980/544 nm. Under optimal conditions, the concentration of IMI producing a 50% saturation of the signal (SC 50 ) is 18.9 ng mL −1 , and the limit of detection is 2.1 ng mL −1 . The method was applied to the determination of IMI in (spiked) paddy water, soil, pear, rice, apple, tomato, pakchoi and cabbage. Average recoveries range from 67.4% to 104.6%, and relative standard deviations from 1.9% to 10.3%. The results correlate well with those obtained by HPLC, the relative correlation coefficient (R 2 ) being 0.9811.
Based on inner filter effect (IFE), a novel immunoassay for imidaclothiz (IMI) was developed by using upconversion nanoparticles (UCNPs) and gold nanoparticles (AuNPs) as labels. Competitive binding of IMI and AuNPs-labeled IMI to the UCNPs-labeled antibody results in a change in the fluorescence of the UCNPs at excitation/emission wavelengths of 980/544 nm.
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高影响因子
JOURNAL OF SOLID STATE ELECTROCHEMISTRY
·
2017
·Vol. 21
·期 6
·1545-1557
·
IF 2.316
Qu Fengjin,Ma Xiaoyan,Hui Yuchen,Chen Fang,Gao Yan,Chen Ying
As enzyme-immobilization and electron-transfer are the key factors for fabricating an enzymatic bioelectrode and its devices, we investigated a strategy to simultaneously improve the two aspects by assistance of the cationic surfactant, stearyltrimethylammonium bromide (STAB). By electrodeposition method, we obtained a multifunctional STAB-modified nanomaterial on electrode surface to improve enzyme-immobilization and electron-transfer. On the one hand, STAB could firmly adsorb a substantial number of enzymes via electrostatic interaction in a favorable orientation on the conductive nanomaterial surface for electron-transfer. On the other hand, STAB acts as a dispersant and stabilizer for traditionally conductive nanomaterials (reduced graphene oxide, carbon nanotubes, and gold nanoparticles) to guarantee their unique properties and form a well-conductive network. Electrochemical measurements demonstrated that enzymatic electrodes based on the nanohybrid possessed fast electron-transfer rate, a large quantity of immobilized enzymes, and good activity toward glucose oxidation or oxygen reduction. The glucose biosensor performed linear response range of 0.01–11.71 mM, detection limit of 3.84 × 10 −3 mM, and sensitivity of 10.42 μA mM −1 cm −2 , while the glucose/O 2 biofuel cell exhibited maximum power density of 121.87 μW cm −2 and open-circuit voltage of 0.663 V. Both of the devices showed better performances than those of devices without STAB or conductive nanomaterials in this work.
Fabrication of surfactant-modified enzymatic electrode and its electrochemical performance
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高影响因子
ACTA PHYSIOLOGIAE PLANTARUM
·
2016
·Vol. 39
·期 1
·1-14
·
IF 1.563
Wang Yang,Ren Tao,Lu Jianwei,Cong Rihuan,Hou Wenfeng,Liu Tao,Hussain Saddam,Li Xiaokun
Inferior tillers typically provide a minimal contribution to the grain yields of rice; however, with the proper regulation of light and nutrients, their yields may be significantly enhanced. The exogenous introduction of gibberellic acid (GA 3 ) may assist with extending the culm lengths of inferior tillers, the sequestration of additional sunlight, and the accumulation of further nutrients. In an attempt to verify our assumption while enhancing the grain yield of inferior tillers, GA 3 was applied to inferior tillers under different nitrogen (N) levels. Morphological alterations, photosynthetic parameters, endogenous GA content, N accumulation, and soluble sugars within the leaves of inferior tillers were assessed, as was the activity of sucrose synthase (SuSase) in the cleavage direction. Our results revealed that the belated emergence and low concentration of endogenous GA 1+3 translated to the stunted growth of inferior tillers, which ultimately had a reduced capacity to harvest sunlight. Furthermore, insufficient sunlight due to asymmetric competition might be the source of the reduction of inferior tiller source and sink activities. Foliar GA 3 spray enhanced the intercepted photosynthetically active radiation (IPAR) and SuSase activity in inferior tillers considerably; however, dry matter and N accumulation provided adequate resources to grains only when the tillers obtained sufficient N. The alterations in soluble sugars indicated that inferior tillers did not respond well to the application of GA 3 under an insufficient N supply. In contrast, when sufficient N was made available, GA 3 -treated inferior tillers received high-intensity light, and additional energy was allocated to the photochemical reactions of photosystem II (PSII). The high quantum efficiency of PSII contributed to the transportation of C- and N-assimilates from the source organ to the sink under adequate N conditions, and eventually increased the grain yields of the inferior tillers.
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