AAPS PHARMSCITECH
·
2019
·Vol. 20
·期 5
·1-12
·
IF 2.608
Ruan Jiuheng,Wan Xiaocao,Quan Peng,Liu Chao,Fang Liang
Chemical penetration enhancers are widely used in transdermal drug delivery system. However, few studies have focused on changes of concentration in chemical penetration enhancers. In this study, the effect of concentrations of enhancers on drug release and its mechanism were investigated. Zolmitriptan (ZOL) was used as a model drug and isopropyl palmitate (IPP) was used as a model enhancer to investigate drug release behaviors in pressure-sensitive adhesives (PSAs). The IPP concentrations were 2, 5, 10, 12, and 15%. Drug release percents increased by 4.8, 11.5, 16, 15.1, and 14.8%, respectively. Interestingly, the linear relationship between concentrations of IPP and release percents was improved in the 0–10% and remained unchanged in the 10–15%. Moreover, thermal and rheology studies were performed to investigate changes of the fluidity of PSAs. FT-IR and molecular dynamics simulation were conducted to confirm the interaction strength among ZOL, IPP, and PSAs. The results elucidated that IPP increased fluidity of PSAs and vied for drug from PSAs. As a result, the interaction among three components played a major role in changing release behaviors of ZOL, but the increased fluidity only worked in the concentration of less than 10%.
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高影响因子
CELLULOSE
·
2019
·Vol. 26
·期 8
·5051-5063
·
IF 3.917
Wang Xue,Jiang Shengjun,Cui Sheng,Tang Yinhan,Pei Zifan,Duan Haoran
Abstract The pore structure of the regenerated cellulose hydrogel was used as a microreactor for generating magnetic MnFe 2 O 4 nanoparticles via in situ co-precipitation technology. Sodium periodate and sodium chlorite were used as oxidants, and the carboxyl modification of magnetic cellulose aerogels was achieved through a two-step oxidation reaction. The method used was convenient and environmental-friendly, and the raw materials were also green and non-toxic. The addition of magnetic nanoparticles promoted the adsorption and enabled the recycling of materials. The results showed that the adsorption equilibrium time was only 120 min and adsorption capacity could be increased by increasing the adsorption temperature. The maximum adsorption capacity of Cu(II) was 73.70 mg/g at 25 °C when the initial concentration of solution was150 mg/L. The adsorption behaviour towards Cu(II) followed the pseudo-secondary reaction kinetics and the Langmuir isotherm adsorption model. According to the results of XPS, carboxyl and hydroxyl groups were the main active adsorption sites for Cu(II). Moreover, all the composite aerogels exhibited good reusability and could be easily separated from the water after adsorption. Graphical abstract The pore structure of the regenerated cellulose hydrogel was used as a microreactor for generating magnetic MnFe 2 O 4 nanoparticles via in situ co-precipitation technology. Sodium periodate and sodium chlorite were used as oxidants, and the carboxyl modification of magnetic cellulose aerogels was achieved through a two-step oxidation reaction. According to the results of XPS, carboxyl and hydroxyl groups were the main adsorption sites for Cu(II). Moreover, all the composite aerogels exhibited good reusability and could be easily separated from the water after adsorption.
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JOURNAL OF ELECTROCERAMICS
·
2019
·Vol. 43
·期 1
·117-122
·
IF 1.966
Cheng Yatong,Niu Yujuan,Xiang Feng,Chang Panpan,Wang Hong
Ba 3 Co 2 Fe 24 O 41 (Co 2 Z)/polyimide(PI) composites were synthesized via in-situ polymerization process, using the micron-sized Co 2 Z particles prepared by the solid-state reaction. X-ray diffractometer (XRD) pattern shows the existence and purity of the aimed phase. Scanning electron microscope (SEM) images show that the Co 2 Z particles are uniformly dispersed in the composites. The testing results of dielectric properties of composites reveal that the dielectric constants of the composites increase with the Co 2 Z content increasing. The frequency-dependent dielectric loss shows that the dielectric loss of samples has the same trend, and that a peak can be observed at about 10 MHz. The saturation magnetization (Ms) of composites depends on the ferrite content, and the Ms. value can reach 8.9 emu/g when the ferrite content is 40 wt% in Co 2 Z/PI composites. Additionally, the coercivity (Hc) of composites show almost no change as the ferrite content increasing, about 100 Oe. The results indicate that the obtained magnetic dielectric composites are new candidates for antenna applications.
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JOURNAL OF MATERIALS SCIENCE
·
2019
·Vol. 54
·期 17
·11435-11447
·
IF 3.442
Deng Chunyan,Li Yinhao,Sun Wenlu,Liu Fengli,Zhang YingXue,Qian Hao
An approach is developed to fabricate supported AuPd nanoparticles (NPs) with high catalytic activity and good separability depending on these amino-modified polymer microspheres (Fe 3 O 4 @PS-NH 2 ). After the careful surface modification with amino groups, the selective adsorption of these magnetic polymer carriers to p -nitrophenol (4-NP) is much available for the improvement of the catalytic activity of immobilized AuPd nanoparticles. Furthermore, the catalytic activity of the bimetallic catalyst could be tunable via controlling the surface coverage of palladium on Au nanoparticles. The catalytic activity of supported AuPd NPs (S-AuPd 250% ) for 4-NP reduction increased 3.78 times compared with that of isolated AuPd NPs. The catalytic activity ( k / m Au ) even reached 479.78 min −1 mg −1 as S-AuPd 150% and was selected as the catalyst. In addition, these supported AuPd nanoparticles are easily and rapidly isolated by magnetic separation. Due to its high stability, these supported AuPd NPs could be recycled for 30 runs without any loss of catalytic activity. Thus, the high catalytic activity and easy separability of this supported AuPd NPs are efficiently combined together, which is showing great potential in nanocatalysts.
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Journal of Ovarian Research
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2019
·Vol. 12
·期 1
·1-7
·
IF 2.469
Wu Gengxiang,Hu Xue,Ding Jinli,Yang Jing
Background The mechanism of the pathological change of polycystic ovary syndrome (PCOS) is still unclear. Previous studies have shown that PCOS is a chronic nonspecific low-grade inflammatory condition, and that heat shock protein (HSP)70 has a potent anti-inflammatory property. So the aim of this study is to investigate the correlation between HSP70 and the hormones and inflammatory factors and to find out the role of HSP70 in the pathogenesis of PCOS.Methods Twenty female Sprague–Dawley (SD) rats (aged 23 days and weighted 80-90 g) were randomly divided into two groups (n = 10 per group), PCOS group and control group. PCOS group were subcutaneously injected with 6 mg/100 g dehydro-epiandrosterone (DHEA) for 20 consecutive days, the control group were subcutaneously injected with a solvent of equivalent amount. All the samples were collected in the morning fasting state, 12 h after the last administration. Histological examinations of ovarian tissues were analyzed. Hormone levels and inflammatory factors levels were measured by enzyme-linked immunosorbent assay (ELISA) kits.Results Serum concentrations of testosterone (T) and luteinizing hormone (LH) were significantly higher in the PCOS group than the control group (P < 0.001), but the concentrations of estradiol (E2), follicle stimulating hormone (FSH) and insulin didn’t show significant difference between these two groups. All the concentrations of inflammatory factors including C-reactive protein (CRP), interleukin (IL)-6, IL-18, and tumor necrosis factor (TNF)-α. were significantly higher in PCOS group than the control group (P < 0.001). The expressions of HSP70 were significantly lower in serum but higher in ovarian tissues in the PCOS group than the control group. Spearman rank correlation analysis showed strong negative correlation of serum HSP70 levels with T, LH and all the detected inflammatory factors.Conclusion The abnormal expression of HSP70 correlated with testosterone and inflammatory factors, which indicates that HSP70 may play an important role in PCOS pathology.
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高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
·
2019
·Vol. 46
·期 1
·101-118
·
IF 2.064
Li Anxia,Yang Xiaoxin,Yu Binglong,Cai Xiulan
In this study, Fe 3 O 4 /nanodiamond nanocomposites (MND) were synthesized by polyglycerol-mediated covalent bonding. The horseradish peroxidase (HRP) was successfully immobilized on PG layer of MND by interaction between functional groups of MND and HRP, where the HRP molecules became tridimensionally connected outside the MND. The physicochemical properties of MND were analyzed by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy measurements, vibrating sample magnetometer, Fourier transform infrared spectroscopy and zeta potential. The optimal conditions for the immobilization of HRP by MND are 7 mg/L, 35 °C and 3 h, respectively. Then, the effects of temperature, pH and storage time on the activity of immobilized enzyme and free enzyme were studied. The results showed that the relative activities of immobilized enzymes were higher than free enzymes at different temperatures, pH and storage time. In addition, the reusability experiments of immobilized enzymes showed that after six cycles, the immobilized HRP retained a relative activity of 75%. Applied to the removal of phenol, the effects of phenol concentration, H 2 O 2 /phenol molar concentration, immobilized HRP concentration and temperature on phenol removal were investigated. The results displayed that the removal efficiency of phenol reached a maximum when the phenol concentration was 75 mg/L, the ratio of H 2 O 2 to phenol was 1, the immobilized HRP concentration was 0.25 mg/L and the temperature was 30 °C. The above results indicate that the immobilized HRP exhibits high removal efficiency and has great potential for removing phenol.
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Journal of Food Measurement and Characterization
·
2019
·Vol. 13
·期 4
·2713-2721
·
IF 1.415
Yan Jun,Huang Xiao-Ping,Wu Ye-Yu,Du Fang-Kai,Tan Xue-Cai,Wang Qi,Zhu Wei-Wei
Abstract Near-infrared (NIR) diffuse reflectance spectroscopy has become an attractive technique for quality assurance of fruits, drugs, vegetables, and foods. In this work, the information on chemical composition of Siraitia grosvenorii was acquired by NIR, and then a calibration model for the prediction of total sugar content (TSC) was developed using chemometric techniques. One hundred and fifty samples were used as calibration set to develop model, while 40 unknown samples were used for prediction, using phenol-concentrated sulphuric acid assay as reference value. Several spectra preprocessing methods and wavelength selection techniques combined with partial least squares regression were compared, and then standard normal variate coupled with Savitzky–Golay derivative was selected for spectra processing and competitive adaptive reweighted sampling method was applied to extract the informative wavelengths related to the prediction of TSC. The performance of the obtained model has been evaluated by external validation, the square of correlation coefficient (R 2 ) are 0.9097 for a separate blind set consists of 40 unknown samples. Additionally, the result of paired t test ( p = 0.3608) illustrated that there is no significant differences between NIR and wet chemistry analysis. These results demonstrated that NIR spectroscopy has the potential to be a time saving and cost-effective method for the determination of the TSC in S. grosvenorii . Graphic abstract
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ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2019
·Vol. 26
·期 24
·25286-25300
·
IF 2.914
Liu Fang,Che Yangli,Chai Qingwen,Zhao Mengfei,Lv Yan,Sun Hui,Wang Yongqiang,Sun Juan,Zhao Chaocheng
Copper and zinc composite oxides (Cu 2 O/ZnO) were synthesized by an impregnation-reduction-air oxidation method. A series of Cu 2 O/ZnO/rGO ternary composites were prepared by coupling with graphene oxide (GO) with different mass fractions in a solvothermal reaction system. The microscopic morphology, crystal structure, and optical characteristics of the photocatalysts were characterized. The degradation of p-Nitrophenol (PNP) and polyacrylamide (PAM) by photocatalytic materials under simulated solar irradiation were studied, and the degradation kinetics were also investigated. The results showed that cubic Cu 2 O was modified by ZnO nanorods and distributed on rGO nanosheets. The ternary Cu 2 O/ZnO/rGO nanocomposites have stronger simulated solar absorption ability and higher photodegradation efficiency than pure ZnO and binary Cu 2 O/ZnO nanocomposites. When the amount of Cu 2 O/ZnO/rGO-10 was 0.3 g L −1 , the degradation rate of 10 mg L −1 PNP reached 98% at 90 min and 99.6% of 100 mg L −1 PAM at 30 min. The photocatalytic degradation processes of PNP and PAM all followed the pseudo-first-order kinetic model. Free radical trapping experiments showed that superoxide radicals were the main active substances to improve photocatalytic efficiency. In addition, after four recycles, the catalytic efficiency of Cu 2 O/ZnO/rGO-10 was still over 90%. It showed that Cu 2 O/ZnO/rGO-10 was a promising catalyst for wastewater treatment because of its good photostability and reusability.
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高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 6
·1-11
·
IF 5.479
Chen Zhipeng,Yu Chen,Xi Jiangbo,Tang Sheng,Bao Tao,Zhang Juan
A hybrid material was synthesized by growing a covalent organic framework (COF) in-situ on the surface of functionalized metal organic framework (MOF). Specifically, the amino-modified MOF (type MIL-68) was obtained by reacting indium(III) nitrate and 2-aminoterephthalic acid. Subsequently, it was reacted with tris(4-formylphenyl)amine and tris(4-aminophenyl)amine to obtain the final hybrid COF. This material overcomes the disadvantage of MOF concerning poor stability in aqueous solution and it combines the advantages of MOF and COF. This MOF@COF hybrid material is shown to be a viable adsorbent for the extraction of sulfonamides by pipette tip solid-phase extraction). Following elution with acetonitrile, the sulfonamides were quantified by high performance liquid chromatography using variable wavelength detection (HPLC-VWD). The structure and morphology of the material was characterized by various techniques. Extraction parameters such as amount of adsorbent, sampling rate, sample pH, elution solvent and sample volume were investigated. Under the optimum conditions, the sulfonamides tested (sulfadimethoxine sulfamethoxazole, sulfamonomethoxine, sulfamethazine, sulfamerazine and sulfadiazine) can be determined over a wide linear range (10–2000 ng·mL −1 ), with low limits of detection (1 ng·mL −1 ) and high precision (RSD <5.2%). The method was applied the determination of sulfonamide residues in (spiked) environmental water, milk and meat samples and gave recoveries in the range from 68.9–103.8%, with RSDs of <6.6%. The packed pipette tip column exhibits excellent stability, reproducibility and high adsorption capacity.
A hybrid sorbent was prepared by controlled growth of a covalent organic framework on amino-modified MIL-68 and packed into a pipette tip for sulfonamide extraction. The sensitivity was dramatically increased after optimized extraction, with limit of detection as low as 1 ng·mL -1
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APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2019
·Vol. 103
·期 15
·6119-6128
·
IF 3.67
Zhang Wenhe,Zhu Tianhui,Li Hengyu,Qin Fengyu,Zhang Feiting,Zhang Rui,Jia Xian,Qin Bin,You Song
Biocatalytic reduction catalyzed by aldo-keto reductases (AKRs) is a valuable approach for asymmetric synthesis of chiral alcohols. In this study, four novel aldo-keto reductases with significant activity and stereoselectivity toward a variety of α-keto esters and halogen-substituted acetophenones were identified by genome mining. Through analysis of the crystal structure and multiple-sequence alignment of the starting AKR YvgN from Bacillus subtilis , residues F25 and W113 were proposed as the key positions that might control the stereoselectivity of YvgN. F25S and F25S/W113F variants of YvgN were able to improve its activity and stereoselectivity toward some α-keto ester compounds and halogen-substituted acetophenone derivatives. In addition, similar enhancement of catalytic activity and stereoselectivity was also found in the other three AKRs with corresponding mutations of starting YvgN.
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高影响因子
Nature Communications
·
2019
·Vol. 10
·期 1
·1-9
·
IF 11.878
Liu Yang,Han Fei,Li Fushan,Zhao Yan,Chen Maosheng,Xu Zhongwei,Zheng Xin,Hu Hailong,Yao Jianmin,Guo Tailiang,Lin Wanzhen,Zheng Yuanhui,You Baogui,Liu Pai,Li Yang,Qian Lei
An ideal anti-counterfeiting technique has to be inexpensive, mass-producible, nondestructive, unclonable and convenient for authentication. Although many anti-counterfeiting technologies have been developed, very few of them fulfill all the above requirements. Here we report a non-destructive, inkjet-printable, artificial intelligence (AI)-decodable and unclonable security label. The stochastic pinning points at the three-phase contact line of the ink droplets is crucial for the successful inkjet printing of the unclonable security labels. Upon the solvent evaporation, the three-phase contact lines are pinned around the pinning points, where the quantum dots in the ink droplets deposited on, forming physically unclonable flower-like patterns. By utilizing the RGB emission quantum dots, full-color fluorescence security labels can be produced. A convenient and reliable AI-based authentication strategy is developed, allowing for the fast authentication of the covert, unclonable flower-like dot patterns with different sharpness, brightness, rotations, amplifications and the mixture of these parameters.
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高影响因子
FIBERS AND POLYMERS
·
2019
·Vol. 20
·期 10
·2017-2024
·
IF 1.439
Ding Yadan,Xu Dan,Shao Hong,Cong Tie,Hong Xia,Zhao Huiying
SiO 2 /polystyrene porous micro/nanofibers with superhydrophobic and superoleophilic properties were prepared by facile electrospinning method. The spindle-beads-on-string structured fibers were found to be more hydrophobic than those without the beads. The doping of nano-SiO 2 endowed the fibers with porous structure, and thus further increased the water contact angle from 139° to 153°. Simultaneously, the oil contact angle of 0° was obtained. The superhydrophobic-superoleophilic micro/nanofibers could selectively absorb oil from water within eight seconds. The oil sorption process followed pseudo-first order kinetic model. The absorption mechanism was proved to be physical encapsulation by Fourier transform infrared technique. The maximum sorption capacity for highly viscous silicone oil was up to 122.7 g/g. It is higher than many recently reported values. The porous micro/nanofibers exhibit significant value in oil-water separation.
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危险品化学品经营许可证（带存储）