NPG Asia Materials
·
2018
·Vol. 10
·期 4
·177-189
·
IF 7.208
Gao Zhong Feng,Sann Ei Ei,Lou Xiaoding,Liu Renyi,Dai Jun,Zuo Xiaolei,Xia Fan,Jiang Lei
Herein, we demonstrate a contact angle (CA)-based naked-eye point-of-care testing platform with rapid pH-responsive superwettability that can switch between superhydrophilic and superhydrophobic properties for quantitative biosensing. The CA of the droplet on the pH-responsive surface approached ~0° at pH 1 and conversely reached 161.4° ± 6.2° at pH 13. We realized the sensitive detection of the pH, urea, and glucose by monitoring the changes in the CA. The traditional invasive diagnosis of diabetes causes pain and brings the risk of infections, such as acquired immune deficiency syndrome (AIDS), hepatitis B, hepatitis C, and syphilis, to the user. To address this issue, we implemented a method for the non-invasive diagnosis of diabetes in human saliva and urine, which avoided the significant drawbacks mentioned above. The accuracy of this method was demonstrated by comparing the results with those from commercial glucometers and theoretical calculations. Interestingly, we successfully monitored glucose levels in sweat before, during, and after cycling. The sensing performance was barely influenced by the temperature, elevation, and droplet color, illustrating promise for expansion to hundreds of millions of potential customers, especially those with color blindness or color weakness. Given its low cost, lack of instruments, and rapid response (within 1 s), this strategy might overcome the limitations of the mechanical stability and durability of superwettable materials and thus might extend the industrial-scale application of bioinspired superwettable systems.
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 1
·1-10
·
IF 5.479
Wen Shao-Hua,Liang Ru-Ping,Zeng Hui-Hui,Zhang Li,Qiu Jian-Ding
A ratiometric fluorometric method is described for the determination of arsenate via its inhibitory effect on the activity of the enzyme acid phosphatase. A nanoprobe was designed that consists of CdSe/ZnS quantum dots (QDs) coated with the terbium(III) complex of guanosine monophosphate (Tb-GMP). The nanoprobe was synthesized from carboxylated QDs, Tb(III) and GMP via binding of Tb(III) by both the carboxy and the phosphate groups. The nanoprobe, under single-wavelength excitation (at 280 nm), displays dual (red and green) emission, with peaks at around 652 nm from the QDs, and at 547 nm from the Tb-GMP coordination polymers. It is shown to be a viable nanoprobe for fluorometric determination of As(V) detection through it inhibitory action on the activity of acid phosphatase (ACP). The enzyme destroys the Tb-GMP structure via hydrolysis of GMP, and hence the fluorescence of the Tb-GMP complex is quenched. In contrast, the fluorescence of the CdSe/ZnS QDs remains inert to ACP. It therefore can serve as an internal reference signal. In the presence of arsenate (an analog of phosphate), the activity of ACP is inhibited due to competitive binding. Thus, hydrolysis of GMP is prevented. These findings were used to design a ratiometric fluorometric method for the quantification of As(V). The ratio of fluorescences at 547 and 652 nm increases linearly in the 0.5 to 200 ppb As(V) concentation range, and the limit of detection is 0.39 ppb. Under a UV lamp, the probe shows distinguishable color from green to red on increasing the concentration of As(V).
Schematic illustration of CdSe/ZnS quantum dot coated with carboxy-PEG and modified with the terbium(III)-GMP complex as a fluorescent nanoprobe for ratiometric determination of arsenate via its inhibition of ACP activity.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Current Medical Science
·
2018
·Vol. 38
·期 5
·853-860
·
IF 0
Zhou Dan-ni,Li Sai-jiao,Ding Jin-li,Yin Tai-lang,Yang Jing,Ye Hong
The polycystic ovary syndrome (PCOS) model was established in rats and correlation between the expression of macrophage migration inhibitory factor (MIF) and cytokinesis with the MAPK signalling pathway in the rat ovary was measured. The PCOS model in rats was established by dehydroepiandrosterone (DHEA). Thirty sexually immature female Sprague-Dawley rats were randomly and equally assigned to three groups: control group, PCOS group, and PCOS with high-fat diet (HFD) group. Serum hormones were assayed by radioimmunoassay (RIA). The ovaries were immunohistochemically stained with MIF, and the expression of MIF, p-JNK and p-p38 was detected by Western blotting in ovaries. The serum testosterone level, LH concentration, LH/FSH ratio, fasting insulin level and HOMA IR index in the PCOS group (6.077±0.478, 13.809±1.701, 1.820±0.404, 10.83±1.123 and 1.8692±0.1096) and PCOS with HFD group (6.075±0.439, 14.075±1.927, 1.779±0.277, 10.20±1.377 and 1.7736±0.6851) were significantly higher than those in the control group (4.949±0.337, 2.458±0.509, 1.239±0.038, 9.53±0.548 and 1.5329±0.7363), but there was no significant difference between the PCOS group and PCOS with HFD group. The expression levels of MIF, p-JNK, and p-p38 in the PCOS group (0.4048±0.013, 0.6233±0.093 and 0.7987±0.061) and PCOS with HFD group (0.1929±0.012, 0.3346±0.103 and 0.3468±0.031) were obviously higher than those in control group (0.2492±0.013, 0.3271±0.093 and 0.3393±0.061), but no significant difference was observed between PCOS group and PCOS with HFD group. It was suggested that MIF may participate in the pathogenesis of PCOS through the MAPK signalling pathway in PCOS rats induced by DHEA.
✓ 已验证
产品关联
DOI
PubMed
MACROMOLECULAR RESEARCH
·
2018
·Vol. 27
·期 1
·10-13
·
IF 1.767
Chen Jie,Dong You-Jia,Jin Fan-Long,Park Soo-Jin
In this study, epoxy-based composites were prepared using diglycidyl ether of bisphenol A (DGEBA) as the matrix, carbon fiber cloth (CFC) as the reinforcing agent, and metallic powder as the conductive filler. The mechanical and electrical properties of DGEBA/CFC and DGEBA/CFC/metallic powder composites were investigated using several techniques. The morphology of the fracture surface was investigated using field-emission scanning electron microscopy. The flexural strength of the DGEBA/CFC composites was found to significantly increase with the addition of CFC. The electrical conductivity of the DGEBA/CFC composites significantly increased with the increasing amount of CFC and further increased after the addition of metallic powders. The electrical conductivity of the DGEBA/CFC composites significantly improved with the addition of a small amount of graphene.
✓ 已验证
DOI
高影响因子
Nanoscale Research Letters
·
2018
·Vol. 13
·期 1
·1-12
·
IF 3.125
Zhao Xiaoyu,Zhang Yingbing,Zhang Jin,Xue Peijie,Wang Yanfei,Liu Rui,Cao Ruge,Zhu Liang,Li Gang,Sha Zuoliang
The highly dispersed silver nanoparticle-loaded poly(styrene-co-acrylic acid) nanocomposites (nAg@PSA) were prepared and characterized by transmission electron microscopy and thermogravimetry. The amount and distribution of colloidal silver per particle were related to the dissociation ratio of carboxyl groups in the PSA sphere. The amount of carboxyl groups was evaluated by a conductivity titration curve. However, the dissociation of carboxyl groups on PSA is difficult to determine accurately via existing methods because the dissociation ratio will increase with increasing impurity ions during titration. We developed a technique to determine the dissociation ratio of PSA without impurity ions. This employs a novel distance-variable parallel electrode system. Thus, the relationship between nano silver distribution and natural dissociation of carboxyl groups on the surface of the PSA spheres was investigated for the first time. Accurately measuring and controlling the dissociation facilitated the production of PSA spheres containing highly dispersed silver nanoparticles. The catalytic performance of as-prepared nAg@PSA catalysts was studied by reduction of 4-nitrophenol. By controlling the amount of natural dissociation ratio of carboxyl group on PSA sphere, dispersion of silver nanoparticles can be designed and attained controllably. They offer easy synthesis, high catalytic performance, and good recyclability.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 16
·11253-11264
·
IF 2.993
Chen Xiaodan,Chen Yufang,Jin Tao,He Li,Zeng Yu,Ma Qian,Li Na
To fabricate a superhydrophobic and durable coating, non-fluorine siloxane solution for the coating was successfully synthesized via a facile one-pot method. The wetting properties and morphology of coatings with different concentration and adding time of additives were studied. Under condition of low water content, the coatings’ superhydrophobicity was improved with the increasing amount of ammonia content, water content, and low-surface-energy material (HTMS) content. However, too more ammonia or water or HTMS would sacrifice the coating’s integrality and lead to the cracking of it. The obtained coatings showed good superhydrophobicity and anti-UV property on plain and even curved substrates, including glass, metal, and polymer. Contact angle and sliding angle of the coating could reach 158° and 1.8°, respectively. What is more, coating on PET filter could be used for oil/water separation with an efficiency of 80%.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2018
·Vol. 29
·期 14
·12144-12151
·
IF 2.324
Liu Yao,Fan Guohua,Qu Yunpeng,Xie Peitao,Wang Zhongyang,Zhang Zidong,Fan Runhua,Yin Xiaowei
Random composites with negative permittivity or negative permeability have developed rapidly while few were accomplished using ceramic materials as the functional fillers. In this work, titanium nitride/polyphenylene sulfide (TiN/PPS) composites with different TiN content were prepared by hot-pressing method. The electrical percolation threshold phenomenon occurred and the conductive mechanism transferred from hopping conduction to metal-like conduction when TiN’s content increased. Negative permittivity in composite with high TiN content was derived from low frequency plasmonic state of free electrons and the plasm-like negative permittivity spectra was analyzed by Drude model. Besides, it’s indicated that the dielectric loss was dominated by conduction loss and polarization loss in composites with high TiN content. Equivalent circuit model was utilized to investigate the impedance properties and suggested that parallel inductances played critical role in achieving negative permittivity.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2018
·Vol. 29
·期 13
·10689-10701
·
IF 2.324
Wang Chenlong,Sun Ting,Zhang Xugang,Chu Mingna,Lv Shixian,Xiang Junyu,Wang JinShuang,Ma Yongjun,Qin Chuanli
It is highly desired to simultaneously introduce active heteroatoms and abundant hierarchical pore structures for enhanced electrochemical performances on carbon materials. Herein, trehalose as a pore-forming agent was added into polyvinylpyrrolidone/melamine formaldedyde resin mixture with high concentrations of nitrogen and oxygen. Then a simple one-step carbonization/activation process was adopted and heteroatom-enriched carbon with hierarchical pores (HPC) was fabricated successfully. HPC/HPC symmetric supercapacitors were assembled using KOH electrolyte. It is clearly demonstrated that due to the pore-forming action of trehalose HPC shows the porous honeycomb, interconnected and worm-like pore structure, which is favorable to enhance the double-layer capacitance. It is confirmed that in our system the three active species of pyridinic nitrogen (N-6), pyrrolic nitrogen (N-5) and quinone type oxygen (O-I) are responsible for the pseudocapacitive behavior. Based on XPS, nitrogen adsorption/desorption isotherms and electrochemical impedance spectroscopy, it is deduced that the ratio-optimized HPC-T30 exhibits high concentration of three active species (8.17 at.%), increased specific area (351.26 m 2 g −1 ) and tuned hierarchical pore structures with substantial micropores (micropore area of 321.68 m 2 g −1 ) and a small amount of mesopores and macropores, which lead to decrease of charge transfer resistance, increase of transfer rate of electrolyte ions in the pores and excellent electrochemical performances. In cyclic voltammetry tests of three-electrode system and galvanostatic charge/discharge tests of two-electrode system, HPC-T30 displays high specific capacitance, 46% and 1.2-time enhancement compared to untreated HPC-T0, respectively. The optimized HPC-T30/HPC-T30 supercapacitor delivers the energy density of 6.69 W h kg −1 in 6 M KOH electrolyte. Furthermore, the supercapacitor shows a capacitance retention of 91.16% up to 6000 cycles and the coulombic efficiency reaches nearly 100% for each charged/discharge cycle, demonstrating its good cyclic stability.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF BIOENERGETICS AND BIOMEMBRANES
·
2018
·Vol. 50
·期 4
·297-305
·
IF 2.914
Ma Long,Dong Jia-Xin,Fu Wen-Rong,Li Xue-Yi,Chen Jing,Liu Yi
In this work, the effects of two non-ionic, non-hydroxyl organic solvents, dimethyl sulfoxide (DMSO) and dimethyl formamide (DMF) on the morphology and function of isolated rat hepatic mitochondria were investigated and compared. Mitochondrial ultrastructures impaired by DMSO and DMF were clearly observed by transmission electron microscopy. Spectroscopic and polarographic results demonstrated that organic solvents induced mitochondrial swelling, enhanced the permeation to H + /K + , collapsed the potential inner mitochondrial membrane (IMM), and increased the IMM fluidity. Moreover, with organic solvents addition, the outer mitochondrial membrane (OMM) was broken, accompanied with the release of Cytochrome c , which could activate cell apoptosis signaling pathway. The role of DMSO and DMF in enhancing permeation or transient water pore formation in the mitochondrial phospholipid bilayer might be the main reason for the mitochondrial morphology and function impaired. Mitochondrial dysfunctions induced by the two organic solvents were dose-dependent, but the extents varied. Ethanol (EtOH) showed the highest potential damage on the mitochondrial morphology and functions, followed by DMF and DMSO.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2018
·Vol. 25
·期 21
·21058-21069
·
IF 2.8
Wang Ziyang,Wang Yan,Yu Cong,Zhao Yanxia,Fan Meixia,Gao Baoyu
In this study, a modified sodium alginate (MSA) composited with TiCl 4 was used to treat the synthetic Ag nanoparticles (AgNPs) water in coagulation-ultrafiltration process. The floc properties and membrane fouling of TiCl 4 and MSA composite coagulants (TiCl 4 + MSA) were investigated by a laser diffraction instrument and ultrafiltration fouling model. The recycle of the AgNP-containing flocs was evaluated by XRD and photocatalytic experiments. The results showed that TiCl 4 + MSA could achieve better coagulation performance than TiCl 4 alone with AgNP and DOC removal up to 97 and 59% at the optimum condition (pH = 5 and dosage = 12 mg TiCl 4 /L). TiCl 4 + MSA produced larger and looser flocs than TiCl 4 and TiCl 4 + SA composite coagulant (TiCl 4 + SA), which was benefit for the inhibition of subsequence membrane fouling. The strongly attached external fouling resistance ( R ef-s ) and the reversible internal fouling resistance ( R if-r) of TiCl 4 + MSA were only 43 and 39.2% of those achieved by TiCl 4 at the optimal coagulation condition. Besides, the adopted AgCl-TiO 2 could be recycled from AgNP-containing flocs. And MSA could promote the form of TiO 2 anatase. It gives us a possible way for silver nanoparticle recycle.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIOPROCESS AND BIOSYSTEMS ENGINEERING
·
2018
·Vol. 41
·期 9
·1271-1281
·
IF 2.139
Cao Weifeng,Wang Yujue,Luo Jianquan,Yin Junxiang,Wan Yinhua
α,ω -Dicarboxylic acids (DC) are versatile chemical intermediates with different chain length. For biosynthesis of DC, to obtain the highly pure product via crystallization, it is required to remove pigments and proteins in fermentation broth. However, a trade-off between decolorization/deproteinization ratio and DC recovery during the purification process was found, which impeded DC production by fermentation. When ultrafiltration (UF) was applied to treat α,ω -dodecanedioic acid (DC 12 ) broth, 93.4% of DC 12 recovery, 80.5% of decolorization ratio and 61.7% of deproteinization ratio were achieved by a PES 3 membrane. However, the membrane technology could not effectively retain the pigments or proteins with low molecular weight when a high DC 12 permeation was required. Meanwhile, the selected activated charcoal or macroporous resins were not good adsorbents for the present system. Furthermore, an integrated process for decolorization and deproteinization was developed. After filtration with PES3 membrane, an activated charcoal was used to remove the small proteins and pigments in the UF permeate. As a result, 91.4% of DC 12 recovery, 94.7% of decolorization ratio and 84.8% of deproteinization ratio were obtained by such two-stage strategy. These results would serve as a valuable guide for process design and practical operation in subsequent industrial application.
✓ 已验证
DOI
PubMed
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2018
·Vol. 102
·期 14
·6047-6056
·
IF 3.34
Zhang Zhi-Jun,Cai Rui-Feng,Xu Jian-He
A nitrilase from Hoeflea phototrophica DFL-43 (HpN) demonstrating excellent catalytic activity towards benzoylacetonitrile was identified from a nitrilase tool-box, which was developed previously in our laboratory for ( R )- o -chloromandelic acid synthesis from o -chloromandelonitrile. The HpN was overexpressed in Escherichia coli BL21 (DE3), purified to homogeneity by nickel column affinity chromatography, and its biochemical properties were studied. The HpN was very stable at 30–40 °C, and highly active over a wide range of pH values (pH 6.0–10.0). In addition, the HpN could tolerate against several hydrophilic organic solvents. Steady-state kinetics indicated that HpN was highly active towards benzoylacetonitrile, giving a K M of 4.2 mM and a k cat of 170 s −1 , the latter of which is ca. fivefold higher than the highest record reported so far. A cascade reaction for the synthesis of optically pure ( S )-β-phenylalanine from benzoylacetonitrile was developed by coupling HpN with an ω-transaminase from Polaromonas sp. JS666 in toluene-water biphasic reaction system using β-alanine as an amino donor. Various ( S )-β-amino acids could be produced from benzoylacetonitrile derivatives with moderate to high conversions (73–99%) and excellent enantioselectivity (> 99% ee ). These results are significantly advantageous over previous studies, indicating a great potential of this cascade reaction for the practical synthesis of ( S )-β-phenylalanine in the future.
✓ 已验证
产品关联
DOI
PubMed
高影响因子