MICROCHIMICA ACTA
·
2019
·Vol. 187
·期 1
·1-10
·
IF 5.479
Sun Yuanling,Dai Yuxue,Zhu Xiaodong,Han Rui,Wang Xueying,Luo Chuannan
A nanocomposite was prepared from a bifunctionalized ionic liquid, chitosan on magnetic nanoparticle-modified graphene oxide (IL/Chit@MGO). It was used in a chemiluminescencc (CL) assay for tetracycline. The materials were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, X-ray powder diffraction, nitrogen adsorption-desorption isotherm, vibrating sample magnetometry and zeta potentials. Subsequently, a tetracycline-binding aptamer (TC-Apt) acting as a recognition element, and G-quadruplex DNAzyme (G-DNAzyme) acting as a signal amplification component were modified on IL/Chit@MGO. So, the bifunctional G-DNAzyme/TC-Apt/IL/Chit@MGO was prepared. The IL/Chit@MGO is found to possess excellent loading capability for TC-Apt. This is attributed to the large specific surface and abundant charge on the surface of IL/Chit@MGO. The composite was used to construct a CL assay for tetracycline. Tetracycline binds to TC-Apt and causes the release of the G-DNAzyme. The latter catalyzes the CL of luminol-H 2 O 2 CL system at pH 7.4. Under optimized conditions, the blue CL at the emission wavelength of 425 nm increases linearly in the 0.16 pM to 2.0 nM concentration range, and the detection limit is 21 fM (at 3σ). The assay is selective, reproducible and stable. The assay was applied to tetracycline detection in practical samples. The apparent recoveries are 98.0% to 101.3% for the milk sample and 97.0% to 102.2% for the water sample.
G-quadruplex DNAzyme (G-DNAzyme) and tetracycline aptamer (TC-Apt) bifunctionalized ionic liquid/chitosan@magnetic graphene oxide (IL/Chit@MGO) was prepared. The nanocomposite was used to construct a chemiluminescence (CL) assay for tetracycline.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2019
·Vol. 26
·期 12
·1-12
·
IF 1.53
Li Ting,Liu Xiaojin,Li Luzhong,Wang Yang,Ma Piming,Chen Mingqing,Dong Weifu
Polydopamine-Functionalized graphene oxide (PDA-GO) was used to form Polyvinyl Alcohol/Chitosan/PDA-GO (PVA/CS/PDA-GO) hydrogels. FTIR, TGA and SEM investigation showed that PDA had been successfully loaded on graphene oxide nanosheets. Adsorption of metal ions onto the novel PVA/CS/PDA-GO hydrogel beads with variations in pH, contact time, initial metal concentration and temperature had been investigated. Adsorption data were well accurately described by Langmuir isotherm and pseudo-second-order kinetic model at the optimum pH 5.5. The maximum adsorption capacities of the PVA/CS/PDA-GO were 210.94 mg·g −1 , 236.20 mg·g −1 and 214.98 mg·g −1 for Cu(II), Pb(II) and Cd(II) ions with 40 C, respectively. Meanwhile, desorption efficiency and reusability of the adsorbents were assessed on basis of six consecutive adsorption-desorption cycles. This work provides a simple and environmentally friendly method to obtain the PVA/CS/PDA-GO hydrogel beads, which really would be a potential recyclable adsorbent for removal of hazardous metal ions in waste water.
✓ 已验证
产品关联
DOI
高影响因子
Hepatology International
·
2019
·Vol. 14
·期 1
·145-160
·
IF 5.49
Zhao Jing,Han Ming,Zhou Li,Liang Pu,Wang Yun,Feng Shenghu,Lu Hongping,Yuan Xiaoxue,Han Kai,Chen Xiaofan,Liu Shunai,Cheng Jun
Background This study aimed to investigate the roles and mechanisms of tenofovir alafenamide fumarate (TAF)/tenofovir disoproxil fumarate (TDF) in treating liver fibrosis. Methods The effects of TAF/TDF on carbon tetrachloride (CCl 4 )-induced liver fibrosis in C57BL/6 wild-type or nonstructural protein 5A transactivated protein 9 (NS5ATP9) knockout mice were studied. The differentiation, activation, and proliferation of LX-2 cells after TAF/TDF treatment were tested in vitro. The expression of NS5ATP9 and activities of transforming growth factor-β1 (TGFβ1)/Sekelsky mothers against decapentaplegic homolog 3 (Smad3) and NF-κB/NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome signaling pathways were detected in TAF/TDF-treated mice and LX-2 cells. The genes related to extracellular matrix accumulation were detected in vivo and in vitro after NS5ATP9 silencing or knockout. Results TAF/TDF significantly inhibited CCl 4 -induced liver fibrosis in mice, and regulated the differentiation, activation, and proliferation of hepatic stellate cells (HSCs). Furthermore, TAF/TDF suppressed the activities of TGFβ1/Smad3 and NF-κB/NLRP3 inflammasome signaling pathways in vivo and in vitro. NS5ATP9 inhibited liver fibrosis through TGFβ1/Smad3 and NF-κB signaling pathways. TAF/TDF upregulated the expression of NS5ATP9 in vivo and in vitro. Finally, TAF/TDF could only show marginal therapeutic effects when NS5ATP9 was silenced and knocked out in vivo and in vitro. Conclusions TAF/TDF prevented progression and promoted reversion of liver fibrosis through assembling TGFβ1/Smad3 and NF-κB/NLRP3 inflammasome signaling pathways via upregulating the expression of NS5ATP9. TAF/TDF also regulated the differentiation, activation, and proliferation of HSCs. The findings provided strong evidence for the role of TAF/TDF as a new promising therapeutic strategy in liver fibrosis.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2019
·Vol. 411
·期 30
·8103-8111
·
IF 3.286
Deng Tao,Hu Shiyou,Zhao Liang,Wu Shengjun,Liu Wei,Chen Tongkai,Fu Tingdan,Wang He,Shi Huifang,Huang Xin-an,Liu Fang
A novel sensitive and selective probe for the important antibiotic vancomycin (Van) has been synthesized by integrating a coumarin and a fluorescein as dual fluorescence reporters and a Van binding peptide d -Ala- d -Ala. Only weak green fluorescence was initially observed, which was mostly attributed to fluorescence self-quenching induced by fluorophore stacking. Upon the binding of Van with the d -Ala- d -Ala peptide, the fluorescence turned on, probably due the disaggregation of fluorophores. The intensity ratio of the dual emission bands I 519 / I 446 exhibited an excellent linear relationship with the concentration of Van increasing from 0–20 μM in synthetic urine. The lowest detection limit was calculated to be 92.8 nM in urine, which made the probe applicable in clinically relevant concentration ranges. The synthetic probe has also shown the potential for Van detection in human serum. More interestingly, this probe has been successfully applied for in vivo imaging of Van in zebrafish.
Graphical Abstract
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICAL AND BIOANALYTICAL CHEMISTRY
·
2020
·Vol. 412
·期 5
·1235-1242
·
IF 3.637
Liu Jinshui,Wu Fangfei,Xie Ao,Liu Chenfu,Bao Huijuan
Water-soluble nonconjugated fluorescent polymer nanoparticles (NFPNs) were prepared from branched polyethylenimine (PEI) and citric acid through an amide condensation reaction in the aqueous phase. The NFPNs were characterized using a transmission electron microscope, Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectra (XPS). The NFPN fluorescence (with excitation/emission peaks at 360/450 nm) was quenched by 2,4,6-trinitrophenol (TNP) at trace concentrations through the inner filter effect and the formation of self-assembled non-fluorescent Meisenheimer complexes of TNP on the NFPN surfaces through acid–base interactions. The complexes effectively enriched TNP from the bulk solution on the NFPN surfaces through acid–base interactions, and the strong overlap between NFPN excitation and TNP absorption peaks contributed to NFPNs having good sensitivity and selectivity for TNP. The method was selective for TNP and was not sensitive to other interfering species. The calibration plot of log( F 0 / F ) versus TNP concentration shows a linear relationship ( R 2 = 0.999) for TNP concentration in the range of 0.5–150 μM. The detection limit for TNP was 0.7 μM. The assay was successfully used to determine TNP in spiked lake water samples, and the recoveries were 96.6–102.7%.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF INCLUSION PHENOMENA AND MACROCYCLIC CHEMISTRY
·
2019
·Vol. 96
·期 1
·69-79
·
IF 1.429
Duan Nannan,Ye Lin,Zhang Ai-ying,Feng Zeng-guo
Abstract A series of PPR-based multiblock copolymers were prepared by using a PPR self-assembled from a distal 2-bromoisobutyryl end-capped ferrocenyl containing derivative Br-TEG-Fc-TEG-Br with 4 β-CDs as initiator to initiate the in situ ATRP of NIPAAm in aqueous solution at room temperature. After the ATRP, about 2 β-CDs were resided on the polymeric backbone through a 7 day dialysing purification, but those β-CDs were all slipped off the polymeric chain through a further 7 day dialysing treatment. It suggested that the resulting multiblock copolymers are really the PPR-based instead of the PR-based ones showing an impeded dethreading behavior of β-CDs and the PNIPAAm blocks attached are not bulky enough as polymeric stoppers to end-cap the β-CD-TEG-Fc-TEG PPRs into the PR-based multiblock copolymers. Graphic abstract A series of PPR-based multiblock copolymers were prepared by using a PPR self-assembled from Br-TEG-Fc-TEG-Br with 4 β-CDs as initiator to initiate the aqueous ATRP of NIPAAm. After the polymerization there are about 2 β-CDs still entrapped on the polymeric chain through a 7 day dialyzing purification. Those threaded β-CDs are all slipped off the polymeric backbone through a further 7 day dialyzing treatment.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2019
·Vol. 30
·期 21
·19598-19608
·
IF 2.195
Li Pengfei,Zhang Hong,Gao Caiyun,Jiang Guoxiang,Li Zhicheng
N egative temperature coefficient (NTC) ceramics based on simple ZnO were prepared and investigated in present work, where slight amount of Al- and La- ions were added as semiconductor dopants, and Cu-ions were selected as the sintering agent and property modificator. All the prepared ZnO-based ceramics have a wurtzite structure and show typical NTC characteristic. For various contents of Al-, La- and Cu- ions in ZnO-based ceramics, ρ 25 can be adjusted from 0.65 kΩ cm to 3.28 MΩ cm, and B values were obtained in range of 2500 K to 5850 K. The ageing treatment at 125 °C for 600 h in air revealed that the ZnO-based ceramics have high thermal stability with the resistance shift < 2%. The complex impedance spectra were applied to analyze the electrical performance.
✓ 已验证
产品关联
DOI
高影响因子
IONICS
·
2019
·Vol. 25
·期 12
·6043-6050
·
IF 2.289
Diao Quan,Zhang Xiaomei,Li Jie,Yin Yuna,Jiao Mingli,Cao Jian,Su Chaohua,Yang Kai
The phenol-formaldehyde (PF) resin microspheres were firstly used as the template in the sensing electrode (SE) preparation process of sensors based on Y 2 O 3 stabilized ZrO 2 (YSZ). The PF resin microspheres were synthesized by a facile hydrothermal method. The high char yield and the few morphological changes of PF resin microspheres before and after sintering at 900 °C indicated the perfect thermal stability at high temperature. The sensors using MnCr 2 O 4 admixed with various contents PF microspheres (0 wt%, 5 wt%, 10 wt%, and 20 wt%) were fabricated and their sensing performances on NO 2 gas were also investigated. The sensor with sensing electrode prepared by MnCr 2 O 4 with 10 wt% PF showed the best NO 2 sensing performance with a response of 110.8 mV to 100 ppm NO 2 as well as the higher sensitivity (87.4 mV/decade) with the NO 2 concentration ranging from 10 to 500 ppm at 550 °C. According to the mixed-potential mechanism, the porous electrode is good for gas penetration, so the gas can easily reach the MnCr 2 O 4 /YSZ/gas triple phase boundary (TPB) to participate in the electrochemical reactions. Additionally, the sensor exhibited excellent selectivity and repeatability, which indicated its potential application in the NO 2 detection.
✓ 已验证
产品关联
DOI
高影响因子
POLYMER BULLETIN
·
2019
·Vol. 77
·期 6
·3223-3235
·
IF 1.858
Jiang Jingzhe,Wei Anqi,Li Jianping,Ji Yue,Qiang Huijun,Jiang Yan,Zhang Hongwen,Liu Hongbo
In this paper, hydroxyl terminated polysiloxane was first prepared by ring-opening polymerization of octamethylcyclotetrasiloxane (D 4 ), which was then modified with acryloyl chloride to obtain acryloyloxy polysiloxane. A light-scattering material was synthesized by copolymerization of acryloyloxy polysiloxane and methyl methacrylate (MMA). The results showed that the transmittance of the material was 88% and the haze was 93% when the ratio of MMA to light-scattering agent was 100:1, the amount of initiator was 0.3%, and the post-polymerization temperature was 50 °C. The TGA data indicated that the material had excellent heat resistance. Therefore, it has a wide range of applications in the field of light-emitting diodes.
✓ 已验证
产品关联
DOI
高影响因子
TRANSITION METAL CHEMISTRY
·
2019
·Vol. 44
·期 7
·655-662
·
IF 1.016
Cui Yanshuai,Liang Bo,Zhang Jin,Wang Ran,Sun Haotian,Wang Longgang,Gao Dawei
Abstract Palladium nanoparticles (Pd NPs) have been drawing great interest as catalysts for water treatment. Herein, high molecular weight polyethyleneimine (PEI) (molecular weight: 70 kDa) was used as template to stabilize Pd NPs. PEI was incubated with disodium tetrachloropalladate, followed by reduction with sodium borohydride. Pd NPs had narrow size distribution with diameter from 3.64 to 6.20 nm. The PEI-stabilized palladium nanoparticles (Pd n -PEI NPs) showed excellent long-term stability and positive zeta potential in phosphate saline buffers with different pH values. In addition, Pd n -PEI NPs exhibited high efficiency for catalysis of 4-nitrophenol (4-NP) in aqueous solution. The catalytic reduction of 4-NP followed the pseudo-first-order behavior, which had the highest catalytic ability ( k nor = 229). The enhanced properties can be attributed to the high stability and smaller size of Pd n -PEI NPs in aqueous solution, resulting from the application of PEI template. This method can be used to prepare highly stable metal nanoparticles with potential applications in catalysis of polluted water in the future. Graphical abstract
✓ 已验证
产品关联
DOI
高影响因子
CELLULOSE
·
2019
·Vol. 26
·期 9
·5455-5466
·
IF 3.917
Dang Baokang,Chen Yipeng,Shen Xiaoping,Jin Chunde,Sun Qingfeng,Li Xiurong
An Fe 3 O 4 -modified lignocellulose (FeLC) composite was fabricated via a sol–gel-assisted hot-pressing process and used for microwave-absorbing and structural materials. The Fe 3 O 4 nanoparticles could be formed in situ at the interface of the lignocellulose (LC) during sol–gel and hot-pressing processing. The obtained FeLC composites exhibited good mechanical and microwave absorption properties. The maximum reflection loss values of the FeLC composite reached − 10.97 dB at 17.04 GHz, and the effective electromagnetic wave absorption reached 90%. Compared with the modulus of rupture (MOR) and modulus of elasticity (MOE) of the LC composite, the maximum MOR and MOE values of the FeLC composite were 26.50 ± 1.16 MPa and 3.015 ± 0.25 GPa, respectively, increasing by 30.2% and 62.1%, respectively. Therefore, the properties of the FeLC could be enhanced via sol–gel assisted hot-pressing.
✓ 已验证
产品关联
DOI
高影响因子
Nature Energy
·
2019
·Vol. 4
·期 5
·408-415
·
IF 54
Li Nengxu,Tao Shuxia,Chen Yihua,Niu Xiuxiu,Onwudinanti Chidozie K.,Hu Chen,Qiu Zhiwen,Xu Ziqi,Zheng Guanhaojie,Wang Ligang,Zhang Yu,Li Liang,Liu Huifen,Lun Yingzhuo,Hong Jiawang,Wang Xueyun,Liu Yuquan,Xie Haipeng,Gao Yongli,Bai Yang,Yang Shihe,Brocks Geert,Chen Qi,Zhou Huanping
Defects play an important role in the degradation processes of hybrid halide perovskite absorbers, impeding their application for solar cells. Among all defects, halide anion and organic cation vacancies are ubiquitous, promoting ion diffusion and leading to thin-film decomposition at surfaces and grain boundaries. Here, we employ fluoride to simultaneously passivate both anion and cation vacancies, by taking advantage of the extremely high electronegativity of fluoride. We obtain a power conversion efficiency of 21.46% (and a certified 21.3%-efficient cell) in a device based on the caesium, methylammonium (MA) and formamidinium (FA) triple-cation perovskite (Cs 0.05 FA 0.54 MA 0.41 )Pb(I 0.98 Br 0.02 ) 3 treated with sodium fluoride. The device retains 90% of its original power conversion efficiency after 1,000 h of operation at the maximum power point. With the help of first-principles density functional theory calculations, we argue that the fluoride ions suppress the formation of halide anion and organic cation vacancies, through a unique strengthening of the chemical bonds with the surrounding lead and organic cations.
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）