MICROCHEMICAL JOURNAL
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2021
·
IF 4.821
Yueting Liao,Yaohai Zhang,Qiyang Zhao,Wei Xiang,Bining Jiao,Xuesu Su
Metal organic framework MIL-101(Cr) was successfully synthesized as a selective adsorbent by a facile self-assembly technique and combined with UPLC-MS/MS for enrichment and determination of neonicotinoids in fruit juices and tea beverages. Therein, MIL-101(Cr) was characterized by Fourier transform infrared spectrometry, scanning electron microscopy, X-ray diffraction, and N 2 adsorption–desorption isotherms. Box-Behnken design was applied to optimize the significant variables including the sorbent amount, pH of the matrix, eluant volume, extraction time and desorption time. The optimized conditions were sorbent amount of 20 mg, eluent volume of 1 mL, extraction time of 5 min and desorption time of 4 min. Under the optimized conditions, excellent sensitivity was achieved with the limit of detection of 0.0019–0.02 μg/L and limit of quantification of 0.0063–0.067 μg/L. Good linearity (R 2 ≥ 0.9988) was obtained within the range of 1–1000 μg/L, and the recovery was 71.04%-101.64% with relative standard deviations (RSDs) of 1.25%-8.82% in spiked samples. The inter- and intra-day RSDs were both<8.54%. The adsorption isotherms investigated for acetamiprid, thiacloprid, and imidacloprid pesticides better fitted with the Freundich adsorption isotherm with bimolecular adsorption capacity of 71.43, 68.49, and 50.38 mg/g, respectively. These results indicate that the nanocomposite is feasible for adsorption of the target analytes at trace amounts from fruit juices and tea beverages.
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高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2021
·
IF 6.165
Ting Huang,Huang-xian Zhang,Xiao-hua Zhang,Da-yong Peng,Xu-liang Nie,Jing Chen,Wan-ming Xiong
A kind of functionalized diallylimidazole ionic liquids (CnDAIMF) was synthesized and applied in the dehydration of D-fructose to produce 5-HMF under the microwave radiation. The results showed that X-ray, 1 H NMR and FT-IR confirmed the production. The target ILs existed in a highly centrally symmetric, and crystalline state at room temperature, with a good thermal stability up to 300 °C (HTD ≥ 340 °C). In the experiments of conversion D-fructose to 5-HMF, 5-HMF could be obtained via the catalysis of diallylimidazole IL whether in water or DMSO. The catalytic performance of these ILs was not much different from that of solid acid (like camphor sulfonic acid or solid carbon sulfonic acid), and which was higher than that of the monoimidazole hexafluorophosphate or imidazole class bromine salt, but there were no obvious changes can be found with the variation of carbon chain length between imidazole rings in diallylimidazole IL. The effects of temperature and solvent on the reaction were more significant. The optimized yield of 5-HMF was 52.59% at 185 °C in a water-C 2 DAIMF solvent (t = 10 min), while 73.71% at 195 °C in DMSO-C 2 DAIMF solvent. Furthermore, six CnDAIMF have a considerable effect on the conversion in water and 5-HMF yield of about 50% could be obtained, which is satisfactory compared with other similar processes, especially in the microwave system of aqueous solution. Therefore, this process may be benefit for many researches and applications related to functionalized ionic liquid research and biomass conversion applications.
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Polymers
·
2021
·Vol. 13
·期 23
·4074
·
IF 4.329
Duanwei Zhang,Fusheng Liu,Sheng Wang,Mengxi Yan,Xin Hu,Mengying Xu
This article proposes a method of increasing thermal conductivity (λ) by improving the λ value of a matrix and reducing the interfacial thermal resistance between such matrix and its thermally conductive fillers. D-GQDs (graphene quantum dots modified by polyetheramine D400) with a π–π-conjugated system in the center of their molecules, and polyether branched chains that are rich in amino groups at their edges, are designed and synthesized. AlN/DG-ER (AlN/D-GQDs-Epoxy resin) thermally conductive composites are obtained using AlN as a thermally conductive and insulating filler, using D-GQDs-modified epoxy resin as a matrix. All of the thermal conductivity, electrically insulating and physical–mechanical properties of AlN/DG-ER are investigated in detail. The results show that D-GQDs linked to an epoxy resin by chemical bonds can increase the value of λ of the epoxy–resin matrix and reduce the interfacial thermal resistance between AlN and DG-ER (D-GQDs–epoxy resin). The prepared AlN/DG-ER is shown to be a good thermally conductive and insulating packaging material.Keywords:thermal conductivity;graphene quantum dots;AlN;epoxy resin;thermally conductive composites
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CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2023
·Vol. 39
·期 6
·1092-1099
·
IF 3.1
Tian Lin,Cheng Cheng,Zhao Zhenwen,Liu Wei,Qi Li
T he construct of artificial nanocatalyts by simulating natural enzymes and thereby bringing new properties for practical applications is still a challenging task to date. In this study, chiral tetrapeptide ( L -phenylalanine- L -phenylalanine- L -cysteine- L -histidine)-engineered copper nanoparticles (FFCH@CuNPs) were fabricated as an artificial peroxidase (POD). More interestingly, the nano-catalysts exhibited chiral identification function. In comparison with other nanocatalysts like L -cysteine-, L -histidine-, chiral dipeptide ( L -cysteine- L -histidine)-, or chiral tripeptide phenylalanine- L -cysteine- L -histidine)-modified CuNPs, FFCH@CuNPs demonstrated a higher POD-mimetic catalytic activity in the 3,3′,5,5′-tetramethylbenzidine (TMB)-H 2 O 2 system and stronger enantioselectivity in the recognition of 3,4-dihydroxy- D , L -phenylalanine ( D , L -DOPA) enantiomers. Considering the strength difference between the intermolecular hydrogen bonding and the π - π interactions, the principle behind the chiral discrimination of D , L -DOPA was explored. Furthermore, contents levels of surface Cu 2+ ions and hydroxyl radicals were found in the FFCH@CuNPs-D-DOPA-TMB-H 2 O 2 system than in the FFCH@CuNPs-L-DOPA-TMB-H 2 O 2 system. Based on these results, a protocol for distinguishing between D , L -DOPA enantiomers through colorimetric recognition was established. This study provides a new insight into design and fabrication of oligopeptides@CuNPs-based chiral nanozymes with improved catalytic performance and features additional to those of natural enzymes.
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APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
He Chen,Chunhong Qi,Luyan Shen,Qiang Fu,Zhiqiang Wang,Zhiyuan Xiong,Youyi Sun,Yaqing Liu
The reduced graphene oxide (rGO) nanosheets were modified by using polymeric nanospheres to adjust the d-spacings between dry rGO nanosheets. The experimental and computational studies show that the incorporation of polymeric nanospheres can effectively increase the d-spacing between dry rGO nanosheets, and meanwhile provide good compatibility of rGO with organic solvents. Specifically, when the d-spacing between nanosheets is greater than 14.0 nm, the dried rGO nanosheets can be well redispersed and stabilized in various organic solvents. This study thus provides a new technology that can produce dry rGO nanosheets with good re-dispersibility and stability in various organic solvents on a large-scale in a more environmental friendly manner.
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ELECTROCHIMICA ACTA
·
2020
·
IF 6.215
You Zhou,Zhengyong Huang,Jian Li,Huijun Liao,Hanxiang Wang,Yu Wang,Guanglei Wu
A compound electrode of carbonaceous materials and NiCo 2 O 4 is extensively studied because of higher capacitance and better rate capability compared to those of pure NiCo 2 O 4 . However, the tedious preparation process, harsh synthesis condition, high consumption, and especially limited electrochemical property by using modifiers hinder its practical application. Herein, modifier-free electrodes (C/NiCo 2 O 4 ) with various morphologies based on D-ribose are successfully synthesized via a one-step hydrothermal-calcination method. D-ribose concurrently acts as carbon source and structure-directing agent. The structure of NiCo 2 O 4 changes from the nanosheets into nanowires after adding D-ribose. Each element is evenly distributed throughout C/NiCo 2 O 4 , significantly improving the electrical conductivity. Furthermore, there is a strong interaction between carbon and NiCo 2 O 4 , which keeps the structure stable. Benefiting from the structural characteristics, the C/NiCo 2 O 4 composites display the improved electrochemical performance. Remarkably, the maximum specific capacitance of C/NiCo 2 O 4 -2 is 1583.9 F g −1 at 2 A g −1 in 3 M KOH aqueous solution, and it exhibits remarkable rate capability of 1354.8 F g −1 even at 20 A g −1 . After 20,000 charge-discharge cycles at 20 A g −1 , a high capacity retention of 90.6% can be achieved. The C/NiCo 2 O 4 -2 is a promising electrode material for supercapacitor. In addition, a dynamic growth mechanism of C/NiCo 2 O 4 under the coordinate bond of metal ions with D-ribose is discussed in the paper.
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高影响因子
INORGANICA CHIMICA ACTA
·
2020
·
IF 2.304
Yan-Long Lan,Xiao-Zeng Li,Tian-Sheng He,Li-Na Zhu
Three coordination polymers (CPs) {[CuL 2 Br]Br·6H 2 O} ∞ (1), {[CuL 2 Cl 2 ]·2.5CH 3 OH·3.5H 2 O} ∞ (2) and {[NiL 2 (NO 3 ) 2 ]·CH 3 CN·3CH 3 OH·H 2 O} ∞ (3) were prepared using a new d -ribose derivative ligand L ( L = 1,2,3,4-tetrakisisoniacyl- β - l -ribopyranose). X-ray single crystal analysis revealed that 1 – 3 all crystallized in the triclinic P 1 space group, all the CPs have 1-D metallomacrocycle strand structures, all the L ligands in the CPs show the same chiral type, and there are four pyridyls bonding with each metal centre arranged into a Δ-propeller configuration in all the three CPs. The same chiral type of the space group and the same chiral type of the propellers should be determined by the same chiral type of the L ligands. In addition, the slightly soluble powders of 1 and 2 displayed probe functions of detecting cysteine, glutathione and N -acetyl cysteine in UV–Vis spectrophotometric analysis of suspensions, which extended the application of UV–Vis spectrophotometry into suspension systems of micron particles.
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ACS Applied Bio Materials
·
2020
·
IF 0
Ji Shen,Juan Qiao,Li Qi
Tuning the efficiency of enzymolysis in different environments is a challenge with important implications for the use of immobilized enzymes in biochemistry, pharmacology, and life science. Here, we demonstrate the use of a thermoresponsive porous polymer membrane for the construction of switchable enzyme reactors, which exhibited membrane surface property changes in diverse temperature environments. The enzyme reactor consisted of block copolymers, poly(styrene−maleic anhydride−oligo methacrylate−methoxyethoxy ethyl methacrylate) [P(St–MAn–OE–ME)], magnetic nanoparticles, and covalently bonded d-amino acid oxidase (DAAO). By varying the temperature between 25 and 39 °C, the self-assembly properties of the enzyme reactor could be controlled. Using d,l-Met as the substrate, the enzymolysis efficiency of the thermoresponsive porous polymer membrane enzyme reactor (t-PPMER) was evaluated by the chiral capillary electrophoresis technique. At higher temperatures, DAAO was embedded in the curled P(OE–ME) chains, resulting in improved enzymolysis efficiency owing to the confinement effect. At lower temperatures, inefficient enzymolysis occurred because of the stretching of the P(OE–ME) chains, which weakened the confinement effect. Remarkably, the enzymolysis rate of t-PPMER at 37 °C (3.1 mM·min–1) was 45 times higher than that at 25 °C (0.066 mM·min–1). The proposed protocol was successfully applied to the DAAO inhibitor screening. This approach capitalizes on the advantageous characteristics of the t-PPMER and provides inspirations for the construction of switchable enzyme reactors and the screening of enzyme inhibitors as potential drugs.
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Advanced Materials Technologies
·
2020
·Vol. 5
·期 7
·2000138
·
IF 5.969
Junjie Hao,Yiwen Li,Xiaoqian Xu,Fenghuan Zhao,Ruikun Pan,Junzi Li,Haochen Liu,Kai Wang,Jiagen Li,Xi Zhu,Marie-Hélène Delville,Ming Zhang,Tingchao He,Jiaji Cheng
Chiral transition metal oxides nanoparticles (NPs) with tunable optical properties are widely accepted as promising toolbox for chiral recognition, stereoselective synthesis, and chiroptical devices. Herein, chirality-based strategy is presented for discrimination of d -glucose from its enantiomer through a cooperative synergy between chiral cysteine capped MoO 2 NPs and the glucose oxidase nanosystem. The valence-state-dependent chirality induced by metal-ligand charge transfer effect is found to be ultrasensitive to its redox environment such as the presence of hydrogen peroxide, which is a key indicator of the stereoselective enzymatic reaction between glucose oxidase and d -glucose. With this know-how, glucose enantiomers can be precisely quantified with a limit of detection of 0.446 µ m . Such a chiral bio-nanosystem would be an ideal platform for a rational design of new types of biosensors, photocatalysts, and chirality-based nanodevices.
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TALANTA
·
2020
·
IF 5.339
Haixia Yu,Yang Chong,Penghao Zhang,Jiaming Ma,Dachao Li
Fiber-based techniques make it possible to implant a miniaturized and flexible surface plasmon resonance (SPR) sensor into the human body for glucose detection. However, the miniaturization of fiber SPR sensors results in low sensitivity compared with traditional prism-type SPR sensors due to limited sensing area. In this paper, we proposed a D-shaped fiber SPR sensor with a composite nanostructure of molybdenum disulfide (MoS 2 )-graphene to improve the sensor sensitivity. Compared with the traditional cylindrical fiber, the planar sensing area on the side-polished fiber makes it easier to modify two-dimensional materials. Chemical vapor deposition (CVD) graphene and CVD MoS 2 were modified on the sensor surface to obtain the MoS 2 -graphene composite nanostructure. π-π stacking interactions were used to modify pyrene-1-boronic acid (PBA) on the graphene. The excellent photoelectric properties of the MoS 2 -graphene composite nanostructure and the ability of PBA to specifically bind glucose molecules improved the glucose detection performance of the SPR sensor. The results show that specific detection of glucose was realized and that the highest sensitivity was achieved with three-layer MoS 2 and monolayer graphene.
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高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2020
·
IF 5.162
Jie Hao,Fangxia Wu,Rong Tang,Yuanyuan Sun,Dehua Liu,Zhenqing Zhang
Oxidized starch (oxStarch) is a major derivative of starch. In present study, 4-acetamide-TEMPO system was firstly applied to prepare specifically oxidized starch, homogeneous 1,4-linked α-D-glucuronan. The impact of oxidant amount, 4-acetamide-TEMPO amount and reaction temperature on the properties of products were investigated. The product structures were characterized with 1 H NMR for degree of oxidation (DO), SEC-MALS for MW, MS for analysis of oxidized oligosaccharides , and in-source fragmented MS for analysis of oxidized polysaccharides . The results showed that the DO of oxStarches increased, but their MWs decreased with the raise of oxidant amount; higher 4-acetamide-TEMPO amount provided higher efficiency of specific oxidation of starch, in which the product has higher DO and MW; no significant difference have been observed between the oxStarches oxidized at 4 and 25 °C, but significant degradation was observed at 50 °C. In each product, having a MW distribution, the portion with smaller size has higher DO. While some unspecific oxidation was still observed observed on the second hydroxyl groups of sugar ring in the following order of priority, position 3 > 2 > 1 > 0.
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JOURNAL OF CELLULAR AND MOLECULAR MEDICINE
·
2020
·Vol. 24
·期 5
·3022-3033
·
IF 4.486
Zheng Li,Haihua Feng,Lu Han,Lu Ding,Bingyu Shen,Ye Tian,Lilei Zhao,Meiyu Jin,Qi Wang,Haiyan Qin,Jiaqi Cheng,Guowen Liu
Chicoric acid is polyphenol of natural plant and has a variety of bioactivity. Caused by various kinds of stimulating factors, acute liver injury has high fatality rate. The effect of chicoric acid in acute liver injury induced by Lipopolysaccharide (LPS) and d -galactosamine ( d -GalN) was investigated in this study. The results showed that CA decreased the aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum and reduced the mortality induced by LPS/ d -GalN. CA can restrain mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-κB) to alleviate inflammation. Meanwhile, the results indicated CA can active nuclear factor-erythroid 2-related factor 2 (Nrf2) pathway with increasing the level of AMP-activated protein kinase (AMPK). And with the treatment of CA, protein levels of autophagy genes were obvious improved. The results of experiments indicate that CA has protective effect in liver injury, and the activation of AMPK and autophagy may make sense.
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高影响因子
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