ANALYTICAL AND BIOANALYTICAL CHEMISTRY
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2020
·Vol. 412
·期 22
·5329-5339
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IF 3.637
He Jincan,Qiu Peipei,Song Jiayi,Zhang Shiyun,Bai Yan
This work described the use of a basic phenothiazine dye (toluidine blue, TB) as a resonance Rayleigh scattering (RRS) and colorimetric probe for the detection of perfluorooctane sulfonate (PFOS). Owing to the electrostatic interactions between TB and PFOS, TB in the presence of PFOS caused great enhancement of RRS signal at dual-wavelength ( I 345 nm and I 506 nm ) and the ratio changes of absorbance ( A 502 nm / A 630 nm ). The RRS enhancement was attributed to the absorption-rescattering resonance effect, the increase of the molecular size, and the enhancement of hydrophobicity. The analytical procedure was implemented by physically mixing TB, Britton-Robinson buffer solution, and PFOS solution (or sample solution) all-in-one, avoiding the tedious pre-derivatization or the preparation of nanoparticles. The whole approach was less than 8 min. Under the optimal conditions, the analytical performance was acquired. The linear ranges for RRS and colorimetry were 0.04–8.0 and 1.0–20 μmol/L, with detection limits of 4.2 nmol/L and 112 nmol/L, respectively. The RRS method was applied to the determination of PFOS in environmental water with recoveries of 93.2–106%. The dual-channel sensor is convenient, rapidly responsive, sensitive, and cost-effective, integrating the advantages of RRS and colorimetry.
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JOURNAL OF MATERIALS SCIENCE
·
2020
·Vol. 55
·期 26
·12091-12102
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IF 3.553
Sheng Peng,Tao Shi,Gao Xiaorui,Tan Yongjian,Wu Dajun,Qian Bin,Chu Paul K.
Cobalt carbonate hydroxide possesses interesting capacitive properties due to the unique crystal structure. Herein, the hierarchical Co 3 O 4 @Co 2 (CO 3 )(OH) 2 dendritic structure was fabricated on carbon cloth with Co 3 O 4 nanoneedles as the inner core to enhance the conductivity. The loading efficiency of Co 2 (CO 3 )(OH) 2 nanowhiskers had improved obviously, and the nanowires provided more electrochemical sites to facilitate the superior electrochemical energy storage capacity of supercapacitor. The dendritic electrode with the core–shell structure had a high area-specific capacitance (1541 mF cm −2 at 1 mA cm −2 ), good rate capacitance (only 18.1% specific capacitance lost when the current density increased to 5 mA cm −2 ), as well as better electrochemical cycle stability (a capacitance retention of 72.1% after 5000 cycles at a high current density of 5 mA cm −2 ). The dendritic Co 3 O 4 @Co 2 (CO 3 )(OH) 2 and activated carbon as cathode and anode, respectively, were used to assemble an asymmetric supercapacitor, possessing the better area-specific capacitance of 87 mF cm −2 as well as well-deserved longevity retaining approximately 97.3% of initial capacitance even after 10,000 cycles at 1 mA cm −2 . The excellent properties stemmed from electro-active sites galore, strong adhesion between the core and shell, superior conductivity, as well as excellent ion transfer. The novel materials and feasible strategy are promising for next-generation hybrid supercapacitor with high performance.
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Drug Delivery and Translational Research
·
2020
·Vol. 10
·期 5
·1267-1277
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IF 2.664
Li Jing,Yang Li,Zhu Chune,Peng Tingting,Huang Di,Ma Xiangyu,Pan Xin,Wu Chuanbin
The ultra-fine particle processing system (UPPS) previously developed by our lab has been used to prepare various microparticulate formulations. Microspheres prepared by UPPS can achieve sustained release with a reduced initial burst compared to the microspheres prepared by the conventional water-in-oil-in-water (W/O/W) double emulsion technique. However, the in vitro drug release mechanism of the microspheres prepared by UPPS is still uninvestigated. This study aimed to investigate the mechanisms of bovine serum albumin (BSA) released from poly ( d , l -lactic-co-glycolic acid) (PLGA) microspheres prepared by UPPS in comparison with microspheres prepared by the W/O/W double emulsion technique. The morphology, in vitro drug release, water uptake, and structural evolution of microspheres prepared by both techniques were evaluated. UPPS microspheres showed solid and compact internal structures without any pores or channels thereby exhibiting a reduced rate of water permeation in the release medium. In addition, the release of BSA in UPPS microspheres was mainly controlled by the erosion of the polymer matrix during the entire process, while BSA was released from W/O/W microspheres by both drug diffusion and matrix erosion. Moreover, the observed surface and internal structural evolution also confirmed their different release mechanisms. This work elaborates the release mechanism of PLGA microspheres prepared by UPPS and facilitates the design of microparticulate formulations.
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BIOLOGICAL TRACE ELEMENT RESEARCH
·
2020
·Vol. 198
·期 2
·557-566
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IF 2.639
Song Miao,Jia Fubo,Cao Zheng,Zhang Haiyang,Liu Menglin,Gao Li
Aluminum (Al)-induced bone metabolism disorder is a primary cause of osteoporosis. Ginsenoside Rg3 (Rg3) has demonstrated therapeutic properties in the treatment of osteoporosis. The present study aimed to identify potential bone protection mechanisms of Rg3 against Al-induced osteoporosis in rats. In this study, forty healthy male Sprague-Dawley rats were randomly allocated into groups in which they were treated with AlCl 3 (64 mg/kg/day) and/or Rg3 (20 mg/kg/day). AlCl 3 was given orally to rats for 120 days, and from the 91st day, treated orally with Rg3 for 30 days. Rg3 attenuated AlCl 3 -induced accumulation of Al by decreasing the bone mineral density in the lumbar spines, femoral metaphysis, and tibia, and inhibited AlCl 3 -induced oxidative stress in rat bone by decreasing the levels of reactive oxygen species and malondialdehyde, while increasing glutathione peroxidase and superoxide dismutase activity. Rg3 facilitated bone formation by increasing the concentration of calcium, phosphorus, amino-terminal propeptide of type I procollagen, and carboxyl-terminal propeptide of type I procollagen, bone alkaline phosphatase activity in serum, and type I collagen, osteocalcin, and osteopontin protein expressions. Rg3 inhibited bone resorption by decreasing the content of N-terminal cross-linking telopeptide of type I collagen, C-terminal cross-linking telopeptide of type I collagen, and tartrate-resistant acid phosphatase 5b activity in serum. Rg3 promoted the mRNA expression of growth regulation factors by increasing transforming growth factor-β1, bone morphogenetic protein-2, insulin-like growth factor I, and core-binding factor α1. The results demonstrate that Rg3 can significantly attenuate Al accumulation, facilitate bone formation, inhibit bone resorption, resist oxidative stress, and promote the expression of factors that regulate growth. The results indicate that Rg3 is effective in alleviating AlCl 3 -induced osteoporosis.
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MICROCHIMICA ACTA
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2020
·Vol. 187
·期 4
·1-7
·
IF 6.232
Huang Qingwei,Zhang Jinli,Li Wei,Fu Yan
Heparin was employed as the stabilizing agent in the synthesis of peroxidase-mimicking Pd nanoparticles. The heparin-capped Pd nanozyme can act as both the signal amplifier and the selective binder of protamine. The most efficient nanozyme with the mean size of 3.5 nm consists of 70.8% metallic Pd 0 and 29.2% Pd 2+ species. Enzyme kinetic studies show that the K m values are 0.036 mM for 3,3′,5,5′-tetramethylbenzidine and 78 mM for H 2 O 2 . Protamine shows strong affinity to the heparin-capped Pd nanozyme, and induces an apparent aggregation of the nanoparticles. This results in a significant inhibition of the peroxidase-mimicking activities. Hence, the oxidation of TMB by H 2 O 2 to a blue product with a maximum absorption at 652 nm is suppressed. Based on this finding, a photometric assay is developed for the determination of protamine. The linear response is in the concentration range 0.02 ~ 0.8 μg mL −1 , and the limit of detection is 0.014 μg mL −1 . This assay presents high selectivity toward other biological substances.
Highly active and selective Pd nanozyme was synthesized through adopting heparin as the capping agent for quantitative determination of protamine.
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Scientific Reports
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2020
·Vol. 10
·期 1
·1-13
·
IF 3.998
Liu Fu,Feng Daoyan,Yang Hui,Guo Xingzhong
Three-dimensional transition metal hydroxide monoliths were facilely fabricated by a sol-gel process accompanied by phase separation in the presence of polyacrylic acid (PAA) and propylene oxide (PO). In the typical ZnCl 2 -PAA-PO system, PAA is used as a phase separation inducer as well as a framework former to control the phase separation and the formation of macrostructures, whereas PO works as a proton scavenger to initiate the gelation of the system and freeze the macrostructures. Appropriate amount of PAA, PO and solvents allow the formation of zinc (Zn) hydroxide monolith with cocontinuous skeletons and interconnected macropores, and the construction mechanism and characteristics of macrostructure are also investigated. The resultant dried gels are amorphous Zn hydroxide monolith with a narrow macropore size distribution (~1 μm). This approach is further used to successfully prepare macroporous single or binary composite transition metal hydroxide monoliths.
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POLYMER BULLETIN
·
2020
·Vol. 78
·期 3
·1213-1230
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IF 2.014
Jiang Yang,Wang Jinyuan,Wu Jian,Zhang Yong
Molybdenum disulfide (MoS 2 ) is a potential additive for rubber enhancement. However, its poor dispersion and weak interaction with matrix limit its further application. To improve the dispersion of MoS 2 in natural rubber (NR) and enhance the interaction of MoS 2 with matrix, single-layered MoS 2 nanosheets are prepared and further modified by cysteine. The modified MoS 2 nanosheets and epoxidized natural rubber (ENR) are premixed and then added into a NR/carbon black compound to obtain a NR/carbon black/ENR-modified MoS 2 nanosheets composite. The reaction between modified MoS 2 nanosheets and ENR is proved by FT-IR spectra. The modified MoS 2 nanosheets can improve the dispersion of carbon black in NR, and ENR can significantly improve the dispersion of modified MoS 2 nanosheets in the composite. The addition of ENR-modified MoS 2 nanosheets premixture can improve the abrasion resistance, increase the crosslink density and control the dynamic mechanical properties of NR. These improved properties can be attributed to the good filler dispersion and enhanced filler–matrix interaction in NR matrix.
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ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2020
·Vol. 27
·期 14
·17043-17053
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IF 3.056
Lin Wenting,Zhang Xiaohan,Li Ping,Tan Yongzhen,Ren Yuan
As a commonly used anti-diabetic drug, metformin (MEF) is frequently detected in different water bodies which pose a potential threat to human health and the ecological environment. In this study, oxidative degradation of MEF under ultraviolet (UV) light was studied, and its influencing factors, photolysis mechanism, and intermediates identification carried out as well. The results showed that the hydroxyl radical contributed 73% during the 6 h MEF photolysis process among the reactive oxygen species (ROS). In addition, triplet excited-state organic matter and singlet oxygen also played a role in the photolysis process. The reaction rates of hydroxyl radical and singlet oxygen with MEF are (6.45 ± 0.4) × 10 9 and (5.4 ± 0.7) × 10 6 L·(mol s) −1 , respectively. By calculating the light screening effect of environmental factors, it is found that the presence of NO 3 − and Cl − had a greater excitation effect on ROS than the screening effect, and generally promoted the photolysis rates of MEF from 90.3 to 193.5% and from 16.1 to 80.6% during the 6-h reaction process, respectively. For bicarbonate and fulvic acid, the light screening effects were dominant and inhibited photolysis rates by 10–52% and 13–71%, respectively. The results demonstrated that the photoreactivity of environmental factors in water is the cause of the different photodegradation rates of MEF. The oxidative degradation product of MEF under UV light was detected by UPLC/Q-TOF as methylbiguanide (MBG), 2,4-diamino-1,3,5-triazine (2,4-DAT), biguanide (BGN), 1,1-dimethylguanidine (1,1-DiMBG), 4-amino-2-imino-1-methyl-1,2-dihydro-1, 3,5-triazine (4,2,1-AIMT), and 2-amino-4-methylamino-1,3,5-triazine (2,4-AMT). The result which showed that the primary sites of ∙OH attacked is consistent with that of density functional theory calculation.
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CELLULOSE
·
2020
·Vol. 27
·期 7
·3989-4005
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IF 4.21
Li Shengnan,Huang Shuo,Xu Fang,Zhao Tianfu,Zhang Fengxiu,Zhang Guangxian
Abstract An eco-friendly hydrophobic flame retardant, ammonium salt of octadecyl phosphate (AMOP) was synthesized and its structure was verified by 1 HNMR, 13 CNMR and 31 PNMR. AMOP imparted flame retardancy and superhydrophobicity to cotton fabrics simultaneously. The water contact angles and limiting oxygen index values of treated cotton reached 161.8° and 27%, respectively. After 30 laundering cycles, the hydrophobicity sustained very well. Thermogravimetric analysis and thermogravimetric-infrared spectroscopy suggested AMOP changed the thermal decomposition path of cotton fibers and the treated sample released less flammable gas during the thermal decomposition process. Cone calorimetry results showed the total heat release and the heat release rate of treated cottons were much lower than those of control cottons. Fourier-transform infrared spectroscopy, energy dispersive X-ray analysis and X-ray photoelectron spectroscopy suggested the AMOP successfully grafted on cotton fabrics through P-O-C groups. Scanning electron micrography showed AMOP caused a rough surface.
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CELLULOSE
·
2020
·Vol. 27
·期 12
·7283-7296
·
IF 4.21
Lu Ruiyang,Yu Yucong,Adkhamjon Gafurov,Gong Wenli,Sun Xiaoqing,Liu Lin
Abstract In this paper, a facile and efficient approach to robust and durable superhydrophobic cotton fabric was presented via in situ CuO deposition and stearic acid (STA) coating. The combined effects of both rough structure and low surface energy endowed cotton fabric (Cot) with superhydrophobicity, water repellency, and self-cleaning property. Moreover, the as-prepared fabric (Cot–CuO–STA) could keep its robust superhydrophobicity under harsh environmental conditions of acidic, alkaline and salt solutions, high temperature, mechanical abrasion and washing. Importantly, the obtained Cot–CuO–STA with WCA of 156.5° had great potential in oil/water separation with high separation efficiency of up to 98.7% for various oils (dichloromethane, trichloromethane, soybean oil, and n-heptane). Further, fascinating permeate flux (more than 1800 L.m −2 .h −1 ) and remarkable recyclability made Cot–CuO–STA a promising application in oil-contaminated water treatment and marine spilt oil cleanup. Graphic abstract Robust and durable superhydrophobic cotton fabric was fabricated for oil/water separation via a facile and efficient route. The resultant fabric exhibited remarkable separation efficiency for different kinds of oils, fascinating permeate flux, and excellent recyclability.
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Journal of Coatings Technology and Research
·
2020
·Vol. 17
·期 5
·1377-1387
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IF 1.815
Peng Xiaoxiao,Liu Yan,Xin Binjie,Guo Hengyi,Yu Yunge
Intended for preparing silane-modified waterborne polyurethane dispersions and then applying them to the development of environmentally friendly nail enamels, the synthesis mechanism was investigated in this paper to determine the optimal technological parameters. Aimed at the synthesis of waterborne polyurethane dispersions, a one-step method was conducted on the prepolymers and the main raw materials, isophorone diisocyanate (IPDI), polycaprolactone diol (PCL), 1,4-butanediol (BDO), 2,2-dimethylol butyric acid (DMBA), (3-aminopropyl) triethoxysilane (APTES), triethylamine (TEA) and solvent water, were adopted. Subsequently, the water-based nail enamel together with its dry film was prepared by pigments and functional additives. Morphological characteristics and chemical composition of dry film of nail enamel were characterized by using atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). The crystallinity of film was analyzed by an X-ray diffractometer (XRD). Benefiting from a thermogravimetric analyzer (TG) and differential thermal analyzer (DSC), the thermal properties of the prepared film were characterized. The hardness, adhesion, glossiness, water absorption, drying time and some other indicators of the water-based nail enamel were tested using a loading pencil hardness tester and other equipment. The experimental results showed the waterborne polyurethane modified by silane coupling agent exhibited favorable film-forming property, glossiness, flexibility, hardness, and adhesion and can be used for developing the environmentally friendly water-based nail enamel with a concentration of silane coupling agent of 1.5%, showing a broad market prospect in the cosmetics field.
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Biomass Conversion and Biorefinery
·
2020
·Vol. 12
·期 6
·2267-2275
·
IF 2.602
Zhang Dongqiang,Chen Xiangyun,Yuan Bing,Yu Fengli,Xie Congxia,Yu Shitao
Hydration of α-pinene catalyzed by a natural deep eutectic solvent (NADES) prepared by oxalic acid dihydrate (OA·2H 2 O) and betaine (Bet), 2.7OA·2H 2 O/Bet, has been studied to develop a more economical and green process for one-step hydration method. It has been found that a homogeneous ternary DES system could be established with OA·2H 2 O and Bet in a simple, convenient, and atomic economy way. Fourier transform infrared spectrum (FT-IR), proton nuclear magnetic resonance ( 1 H NMR), thermogravimetry (TG), and differential scanning calorimetry (DSC) have been applied to confirm the formation of hydrogen bonding between OA, H 2 O, and Bet. With the consideration of catalytic activity, selectivity, and ability to recycle, 2.7OA·2H 2 O/Bet has been screened out to be a promising catalyst for hydration of α-pinene due to its appropriate acidic properties and solubility. In this catalytic system of hydration, water, as one of the reactants, both assisted in the formation of DES and acted as the dispersing agent. Correspondingly, an “emulsifying reaction at the reaction temperature and solid-liquid separation below room temperature” characteristic of this specific catalytic hydration of α-pinene has been achieved.
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