International Journal of Nanomedicine
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2019
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IF 4.471
Fei Tong,Xiangyuan Tang,Daojun Liu
Background Hepatic ischemia/reperfusion-induced pancreatic islet injury (HI/RIPII) was an important pathophysiological phenomenon in clinics. In the present study, we observed the effects of phycocyanin on HI/RIPII. However, the half-life of phycocyanin was extremely short and limited its use in vivo.Materials and methods In order to overcome this shortcoming, poly(ethylene glycol)-b-(poly(l-glutamic acid)-g-polyethylenimine) (PEG-b-(PG-g-PEI)) was synthesized and estimated as a nanocarrier for lengthening delivery of phycocyanin through the abdominal subcutaneous injection in rats. Phycocyanin (isoelectric point=4.3) was encapsulated with PEG-b-(PG-g-PEI) via electrostatic interactions at pH 7.4.Results In vitro phycocyanin was fast and efficiently encapsulated and showing efficient loading and sustained release. In vivo the anti-HI/RIPII function of phycocyanin/PEG-b-(PG-g-PEI) complex was surveyed in rats using free phycocyanin as the controls, and the results showed that phycocyanin/PEG-b-(PG-g-PEI) complex reduced HI/RIPII property and enlarged islet functionality.Conclusion These results suggested that PEG-b-(PG-g-PEI) might be treated as a potential phycocyanin nanocarrier.
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高影响因子
ACS Omega
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2018
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IF 0
Shengli Wang,Yanping Jia,Lianfa Song,Haifeng Zhang
Hydroxylamine (HA) can react with hydrogen peroxide (H2O2) to generate hydroxyl radical (HO•), but the reaction rate between them is very slow (2.2 × 10–4 M–1 s–1). We propose a new system to accelerate the formation of aminoxyl radical (NH2O•) by the addition of cerium [Ce(IV)] to induce the continuous production of HO• through reaction with H2O2. We also investigate the decolorization and mineralization of rhodamine B (RhB) and mechanism in the Ce(IV)/H2O2/HA system. The initial pH plays a significant role in decolorization of RhB. In this work, observation of the rapid decolorization process after 60 min revealed that approximately 80% of RhB was degraded at the initial pH of 4.0. The HO• radicals were considered as the primary reactive oxidant in the system, during its investigation through coumarin capturing, benzoic acid capturing, and radical quenching experiments. The results of the present study suggest that the addition of Ce(IV) can greatly enhance the production of HO•, and the rapid decolorization and mineralization of RhB can occur through the Ce(IV)/H2O2/HA system at acidic pH conditions.
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JOURNAL OF ETHNOPHARMACOLOGY
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2019
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IF 3.414
Bin Xie,Yuan-Yuan Lu,Zhuo-Hui Luo,Zhao Qu,Chun-Ge Zheng,Xin-An Huang,Hong-Yan Zhou,Ying-Jie Hu,Xiao-Ling Shen
Ethnopharmacological relevance Marsdenia tenacissima (Roxb.) Wight et Arn is a vine distributed in southwest area of China and used in folk medicine for treatment of tumors. Recent decades of studies on this plant reveal its synergistic effects with certain anticancer drugs in cancer therapy. In our previous study, an extract ETA which contains total aglycones made from M. tenacissima significantly enhanced antitumor activity of paclitaxel in tumor-bearing mice. However, the effective constituents in ETA and the underlying mechanisms remain unclear. Aim of the study Reveal the active components in ETA as well as the molecular mechanism in enhancing antitumor efficacy of paclitaxel. Material and methods Main constituents in ETA were purified by chemical methods. Effects of the purified constituents on metabolic activity of CYP450 enzymes were evaluated in human liver microsomes. Ability of the constituents to enhance antitumor activity of paclitaxel were investigated in nude mice bearing HeLa tumors. Pharmacokinetic study was performed in SD rats . Molecular docking was carried out for investigation of drug-protein interactions. Results Three main C 21 steroidal aglycones, 11α- O -tigloyl-12β- O -acetyl-tenacigenin B ( MT1 ), 11α- O -2-methylbutanoyl-12β- O -tigloyl-tenacigenin B ( MT2 ) and 11α- O -2-methylbutanoyl-12β- O -acetyl-tenacigenin B ( MT3 ), together with tenacigenin B ( MT4 ) was prepared from ETA. Among them, MT1 , MT2 and MT3 strongly inhibit the metabolic activity of CYP3A4 . MT2 also showed inhibitory effects on CYP2C8 , CYP2B6 and CYP2C19 . In HeLa tumor xenografts, MT1 , MT2 and MT3 (30 mg/kg) did not affect tumor growth themselves, but significantly enhanced paclitaxel-induced growth inhibition. In addition, coadministration of MT2 with paclitaxel resulted in significant reduction of liver CYP2C8. In pharmacokinetic study, MT2 significantly increased the blood concentration of paclitaxel with increased AUC value by 2.2–5.3 folds. Molecular docking analysis suggested hydrophobic interaction modes of tenacigenin B derivatives with CYP3A4, and also the essential roles of the C-11 and C-12 ester groups for effective interaction with CYP3A4. Conclusion Our study proves that, 11α- O -tigloyl-12β- O -acetyl-tenacigenin B, 11α- O -2-methylbutanoyl-12β- O -tigloyl-tenacigenin B and 11α- O -2-methylbutanoyl-12β- O -acetyl-tenacigenin B, which are the main constituents of ETA, are active inhibitors of CYP3A4 with potential to increase therapeutic efficacy of anticancer drugs that are substrates of CYP3A4. Tenacigenin B derivatives with C-11 and C-12 ester group substitutions, or at least a large part of them, are active components in ETA and M. tenacissima to enhance in vivo antitumor efficacies of paclitaxel.
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高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
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2018
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IF 2.932
Yuping Shen,Man Wang,Yufei Chen,Lili Xu,Yi Lu,Yiying Zhou,James P. Tam,Feng Han,Huan Yang,Xiaobin Jia
Sagittatoside B, a rare secondary flavonol glycoside in Epimedii Folium, has much better in vivo bioactivities than its original glycoside epimedin B. Its preparation methods, such as acidic hydrolysis, are of low efficiency, and byproducts are generated. The objective of this study was to establish a novel catalysis system for convenient preparation of this compound based on recyclable and integrated biphase enzymatic hydrolysis. β -glucanase was selected from five commercial enzymes based on the best catalysis performance. After optimization of the conditions, the biphase system was constructed with propyl acetate and HAc-NaAc buffer (pH 4.5) (1:1 , v/v ) containing β -glucanase/epimedin B (1:2, w/w ), and the hydrolysis was performed at 60 °C for 1 h. Consequently, epimedin B was completely hydrolyzed to sagittatoside B, and 95.7% of the product was transferred into the organic phase. Moreover, a high conversion ratio of 94.0% was achieved, even after the enzyme solution was used for six cycles. Additionally, the procedure was much simplified compared with conventional enzymatic hydrolysis. The newly proposed strategy is an efficient and promising approach for the preparation of sagittatoside B in industrial applications.
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高影响因子
Micro & Nano Letters
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2019
·Vol. 14
·期 5
·501-504
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IF 0.975
Ya Liu,Yuqing Miao
The quadrangular (QA) bismuth oxychloride nanoflakes (NFs) were synthesised by a simple solvothermal reaction. They were characterised by scanning electron microscope, transmission electron microscope and X-ray diffractometer. As catalysts, the square NFs exhibited excellent catalytic performance in the reduction of 4-nitrophenol (4-NP) and the degradation of rhodamine B (RhB). The complete reduction of 4-NP to 4-aminophenol was obtained in 30 s and the nearly complete degradation of RhB in 20 min.
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International Journal of Applied Ceramic Technology
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2018
·Vol. 15
·期 5
·1146-1156
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IF 1.165
Qingliang Shan,Jianbao Hu,Yanmei Kan,Dewei Ni,Le Gao,Xiaowu Chen,Shaoming Dong
Si-B-C ceramics were prepared through reaction sintering, and the influence of Al 2 O 3 addition on the high-temperature (1100-1300°C) oxidation behavior of the material under air atmosphere was studied. The erosion behavior and mechanism are determined from the measurement of weigh changes, microstructure observations, and characterization of the generated oxides on postexposure specimens. Results show that Al 2 O 3 is enriched in the oxidized layer, inhibiting the volatilization of B 2 O 3 and impeding the crystallization ability of oxide (cristobalite). Narrower erosion layer and less weigh change are observed with Al 2 O 3 . Low-frequency Raman results reveals that with the increase in Al 2 O 3 , the bending vibrations of the BO 4 units and B-O-B stretching of the metaborate ring relative intensity are enhanced. Furthermore, high-frequency Raman results shows that the relative proportion of high-dimensional vibration modes Q 3 and Q 4 which result in a higher viscosity of melt and a greater resistance of oxygen diffusion are positively correlated with Al 2 O 3 .
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高影响因子
ACS Applied Energy Materials
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2018
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IF 0
Ting Luo,Kai Pan
Thermoelectric (TE) generators are an appealing, ecofriendly energy harvesting technology capable of converting temperature gradients into electricity. Carbon nanotube (CNT) filled organic composites typically offer the best potential for making cheaper TE materials. In this study, a block copolymer poly(ether-b-amide12) (PEBA) with excellent flexibility and mechanical properties was used to fabricate TE materials via blending CNTs. After doping PEBA with lithium chloride (PEBA-Li+), two types (p-type and n-type) of CNT filled PEBA-Li+ (CNT-PEBA-Li+) TE composites were obtained via a simple one-step casting method. Here, the n-type CNT is prepared by diethylenetriamine doping treatment of the pristine CNT (p-type). The resultant TE materials exhibited a bilayer heterogeneous (BH) structure comprised of a thermally nonconductive layer and a conductive layer. The Seebeck coefficient (S) and electrical conductivity (σ) (under the application of temperature gradient 20 K) for the obtained p-type CNT-PEBA-Li+ bilayer heterogeneous film (BHF) are 36.88 μV/K and 456 S/m and for the n-type CNT-PEBA-Li+ BHF are −33.25 μV/K and 492 S/m, respectively. We constructed this novel TE device by integrating p- and n-type elements. The results showed that generated TE voltages for the module made of three TE couples were able to reach 120 mV for a temperature gradient of 60 K. The TE device construction was more efficient and simpler due to the BH structure, as only two BHF types were needed and no thermal insulating layer was necessary. In addition, our TE device is flexible throughout the entire structure. These novel flexible TE composites may benefit future organic TE materials research and promote the application of flexible and wearable power-conversion devices for next-generation power generators and waste-heat-recovery systems.
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NEW JOURNAL OF CHEMISTRY
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2018
·Vol. 42
·期 11
·8537-8543
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IF 3.201
Zhifeng Zhang,Wenwen Wang,Zhentan Lu,Ke Liu,Qiongzhen Liu,Dong Wang
Poly(glycidyl methacrylate)-b-polystyrene (PGMA-b-PS) block copolymers were synthesized by two steps with 1,1-diphenylethylene (DPE) as the chain transfer reagent. The molecular weights and chemical structures of block copolymers were characterized by GPC, FTIR and NMR analyses. Then PGMA-b-PS fibers were fabricated under a shear field using methanol as the antisolvent and glycerin as the shear medium. The shear speed, the concentration of block copolymer solution and the ratios of methanol to glycerin were controlled and regulated. The morphologies of block copolymer fibers were investigated by SEM. Finally, immobilization of bovine hemoglobin on block copolymer fibers was carried out which has potential applications in blood substitutes.
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高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2018
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IF 3.927
Yuwei Pan,Minghua Zhou,Ying Zhang,Jingju Cai,Bing Li,Xuejie Sheng
An efficient heterogeneous catalyst, pre-magnetized Fe 0 (pre-Fe 0 ) could significantly activate persulfate (PS) to remove Rhodamine B (RhB). The effect of pH, Fe 0 and PS dose on the RhB removal in the pre-Fe 0 /PS and Fe 0 /PS processes were investigated, and optimized by response surface methodology (RSM) to analyze the rate constants of the RhB removal in the pre-Fe 0 /PS process and Fe 0 /PS process ( f ). High RhB removal was obtained at low pH and high dose of Fe 0 and PS in both systems. Low Fe 0 and high PS dose and large pH would result in big value of f , and the simulated maximum f of 44.3 was achieved at 2 mM Fe 0 , 16 mM PS and pH 9. The synergetic factor of pre-Fe 0 /PS (45.6) was larger than that of Fe 0 /PS (21.4). The pre-Fe 0 /PS process presented 2.1–37.5 folds enhancement than the Fe 0 /PS process for the degradation of RhB. The RhB removal in the pre-Fe 0 /PS process was 1.5–11.2 folds enhancement than that of the Fe 0 /PS process in the presence of different anions and cations. Scanning Electron Microscope (SEM) results and the larger intensity of DMPO-SO 4 − adduct signal in the Electron Paramagnetic Resonance (EPR) confirmed the primary role of sulfate radicals generated from the reaction of PS with Fe 0 in the contaminant degradation. The pre-Fe 0 /PS process exhibited advantages over other processes to remove RhB in terms of contaminant removal, working pH range and chemical dose. Therefore, the pre-Fe 0 /PS process is a cost-effective approach for degrading RhB.
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JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2018
·Vol. 29
·期 24
·20959-20967
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IF 2.324
Wu Xiang-Feng,Zhang Chen-Xu,Wang Yu-Duan,Su Jun-Zhang,Zhang Jia-Rui,Feng Yan-Mei,Zhang Mi,Tong Xin,Zhang Wei-Guang,Sun Xiu-Guo
The Ag 2 CrO 4 /SnO 2 n–n type heterojunction has been fabricated by coupling Ag 2 CrO 4 particles with SnO 2 nanorods via an in situ synthetic method. The photocatalytic degradation mechanism of the as-prepared heterojunction has also been discussed. Characterization results revealed that the as-fabricated Ag 2 CrO 4 /SnO 2 composites could reinforce the photo-degradation competencies for rhodamine B dilute solution compared to pure Ag 2 CrO 4 and SnO 2 samples. As the increase in the molar ratios of Ag 2 CrO 4 –SnO 2 , the photocatalytic degradation efficiency appeared to the tendency of first increasing and then decreasing. When it was 4:10, in 90 min, the as-obtained samples possessed the vintage photocatalytic degradation efficiency of 95.8% among of pure SnO 2 , Ag 2 CrO 4 and the as-prepared composites with various molar ratios, respectively. Furthermore, the Ag 2 CrO 4 and SnO 2 were connected via chemical bonds to form the homogenous heterojunction. It could boost the separation and transfer of the photogenerated holes and electrons. In addition, the holes, hydroxyl and superoxide radicals played a major role during the photodegradation process.
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高影响因子
Arabian Journal of Chemistry
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2018
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IF 2.969
Junyan Kuang,Zipeng Xing,Junwei Yin,Zhenzi Li,Siyu Tan,Meng Li,Jiaojiao Jiang,Qi Zhu,Wei Zhou
Ti 3+ self-doped rutile/anatase/TiO 2 (B) mixed-crystal tri-phase heterojunctions photocatalysts are fabricated via hydrothermal approach and mechanochemical process, followed by in-situ solid-state chemical reduction approach. The as-prepared samples are characterized by X-ray diffraction, Raman, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV–vis diffuse reflectance spectroscopy. The photocatalysts are consisted by anatase/rutile TiO 2 nanoparticles and 1D TiO 2 (B) single-crystalline nanorods, which form rutile/anatase/TiO 2 (B) tri-phase heterojunctions. The visible-light-driven photocatalytic degradation rates of methyl orange and phenol are up to ∼98 and 97%, which are 2.2 and 1.8 times higher than that of commercial Degussa P25, 2.3 and 2.2 times higher than that of pure TiO 2 (B) as well. The enhancement can be attributed to the synergistic effect of special nanostructure, tri-phase heterojunctions, oxygen vacancy and Ti 3+ self-doping, which facilitates the absorption of visible light and the spatial separation of photo-generated charge carriers. This work provides a new perspective for designing high-active visible-light-driven photocatalyst in future.
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高影响因子
APPLIED SURFACE SCIENCE
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2018
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IF 4.439
Wenfei Zhou,Mo Yang,Zhi Zhao,Shaopeng Li,Zhiqiang Cheng,Jinsong Zhu
Surface-grafted polymer brushes have been long reported as a desired matrix for biosensing applications, owing to enhanced immobilization capacity and anti-fouling properties. However, simultaneous optimizing binding signal and minimizing non-specific adsorption using polymer matrix is still a challenge, due to the lack of systematic structural and composition optimization at molecular level. In this research, a series of block copolymer brushes with controlled hierarchical architectures, poly [oligo (ethylene glycol) methacrylate- b -glycidyl methacrylate] (POEMGA- b -PGMA) were prepared by two-stage surface-initiated polymerization. Surface plasmon resonance imaging (SPRi), as a real-time and label-free biosensing technology, was used as means to evaluate their detecting performances of bio-interactions. In contrast to one-layer poly (glycidyl methacrylate) (PGMA), 4.7-fold enhancement of signal-to-background ( S / B ) was achieved in bi-layer POEGMA- b -PGMA surface, by using rabbit IgG (R-IgG, in 10% serum) and a microarray of goat-anti-rabbit IgG (G-R-IgG) as the system of study. Interestingly, the binding signals and anti-fouling performances of the polymer brushes could be enhanced simultaneously by increasing the length of the monomer in the primary layer. Theoretically, it mainly owed to the formation of a densely packing protective primary layer against non-specific physical adsorption and a spatially optimized secondary layer of minimized steric hindrance that allowed optimum binding of analytes.
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