INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2018
·
IF 3.141
Weiping Kong,Yong Liu,Fujian Liu
Efficient micro-meso-macroporous solid acids spheres with controllable acid strength were successfully synthesized by simultaneous grafting of −SO3H and −SO2CF3 onto the network of commercial XAD-4 resin. The synthesized solid acids are designated as XAD-4-SO3H and XAD-4-SO3H-SO2CF3. Various characterizations show that XAD-4-SO3H and XAD-4-SO3H-SO2CF3 possess high BET surface areas, hierarchical porous structures with combined micro-meso-macropores, high concentrations of acid sites, and strong acid strength. Catalytic tests show that XAD-4-SO3H and XAD-4-SO3H-SO2CF3 exhibit superior activities and good reusability in various acid-catalyzed reactions including esterification of acetic acid with cyclohexanol, acylation of anisole with acetyl chloride, and catalytic synthesis of bisphenol A. Their activities were better than the solid acids of Amberlyst-15, SBA-15-SO3H-0.1, H3PW12O40, and acidic zeolites. This work develops a new method for scalable transformation of commercially macroporous resin into efficient porous solid acids, which promotes their wide use in industrial catalysis.
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JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2019
·
IF 2.298
Yue Sun,Weisheng Zheng,Rajendra Prasad Singh,Li Chen
In the current work, poly(4-vinylpyridine) (P4VP) was grafted on a macroporous polystyrene resin via free-radical polymerization by using the pendent vinyl group. The grafting conditions such as swelling agent, initiator concentration, reaction temperature, and amount of 4-vinylpyridine (4VP) monomer were optimized, and three resins with different 4VP monomer amounts (SC-1, SC-2, and SC-3) were chosen as adsorbents. P4VP-grafted resins were characterized by scanning electron microscopy, N2 sorption/desorption isotherms, Fourier transform infrared, and X-ray photoelectron spectroscopy. The sorption properties of 2-naphthalenesulfonic acid (NSA) on three resins were comparatively investigated. The experimental data revealed that the sorption process on three resins fitted well with the pseudo-second-order kinetics equation, and the equilibrium isotherms were in good agreement with the Langmuir model. The NSA sorption onto resins was an endothermic and spontaneous process, and SC-3 loaded with NSA can be efficiently regenerated by NaOH and ethanol mixed solution after sorption. The maximum sorption capacities of three resins indicated that P4VP-grafted resins possess good sorption ability toward NSA.
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BRITISH JOURNAL OF PHARMACOLOGY
·
2019
·Vol. 176
·期 14
·2627-2641
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IF 6.583
Zheng Xu,Chunpeng Zou,Weihui Yu,Sujing Xu,Lan Huang,Zia Khan,Jingying Wang,Guang Liang,Yi Wang
Background and Purpose Hypertension adversely affects the kidney and is the second leading cause of kidney failure. Overproduction of angiotensin II greatly contributes to the progression of hypertensive kidney disease. Angiotensin II has recently been shown to activate STAT3 in cardiovascular cells. However, the underlying mechanisms of STAT3 activation by angiotensin II and downstream functional consequences in the kidneys are not fully understood. Experimental Approach C57BL/6 mice were treated with angiotensin II by subcutaneous infusion for 1 month to develop nephropathy. Mice were treated with either adeno-associated virus expressing STAT3 shRNA or STAT3 inhibitor, S3I-201. Human archival kidney samples from five patients with hypertension and five individuals without hypertension were also examined. In vitro, STAT3 was blocked using siRNA or STAT3 inhibitor S3I-201 in the renal proximal tubular cell line, NRK52E, after exposure to angiotensin II. Key Results Angiotensin II activated STAT3 in kidney epithelial cells through engaging toll-like receptor 4 (TLR4) and JAK2, which was independent of IL-6/gp130 and angiotensin AT 1 receptors. Angiotensin II-mediated STAT3 activation increased fibrotic proteins and resulted in renal dysfunction. Both STAT3 inhibition by the low MW compound S3I-201 and TLR4 deficiency normalized renal fibrosis and dysfunction caused by Ang II in mice, without affecting hypertension. Conclusions and Implications Our study reveals a novel mechanism of STAT3 activation, induced by angiotensin II, in kidney tissues and highlights a translational significance of a STAT3 inhibitor as potential therapeutic agent for hypertensive kidney disease.
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SENSORS AND ACTUATORS B-CHEMICAL
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2019
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IF 6.393
Lu Fan,Yurong Yan,Bin Guo,Min Zhao,Jia Li,Xintong Bian,Haiping Wu,Wei Cheng,Shijia Ding
Alloy nanomaterials with various morphologies have showed their potential application in electrochemical signal amplification. However, it is still challenging to fabricate stable multimetallic nanomaterials with large surface area and strong electrochemical activity for the further enhancement of electrochemical sensors’ performance. Here, the trimetallic AgPtCo nanodendrites (NDs) were synthesized as powerful redox probe and highly efficient signal amplifier for electrochemical signal readout. A robust and ultrasensitive electrochemical immunosensor, based on AgPtCo NDs and magnetic nanocomposites (Fe 3 O 4 @SiO 2 @Au MNCs), was successfully developed to detect serum human epididymis protein 4 (HE4). The established method, drawing upon the strong electrochemical activity of AgPtCo NDs and the enrichment and separation effect of MNCs, exhibited a wide linear range (0.001–50 ng mL −1 ) and a low detection limit (0.487 pg mL −1 ). Besides, the developed sensor was applied to analyze the concentration of HE4 in real samples and the results achieved were consistent with those of clinical methods. Thus, this AgPtCo NDs and MNCs based electrochemical immunosensor might become a powerful alternative approach for ultrasensitive detection of various serum biomarkers associated with early diagnosis and treatment of diseases.
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Scientific Reports
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2017
·Vol. 7
·期 1
·1-11
·
IF 4.259
Huang Haiying,Tao Xuanyu,Jiang Yiming,Khan Aman,Wu Qi,Yu Xuan,Wu Dan,Chen Yong,Ling Zhenmin,Liu Pu,Li Xiangkai
Soil contamination by PAH and heavy metals is a growing problem. Here, we showed that a new isolate, Pseudomonas brassicacearum strain LZ-4, can simultaneously degrade 98% of 6 mM naphthalene and reduce 92.4% of 500 μM hexavalent chromium [Cr (VI)] within 68 h. A draft genome sequence of strain LZ-4 (6,219,082 bp) revealed all the genes in the naphthalene catabolic pathway and some known Cr (VI) reductases. Interestingly, genes encoding naphthalene pathway components were upregulated in the presence of Cr (VI), and Cr (VI) reduction was elevated in the presence of naphthalene. We cloned and expressed these naphthalene catabolic genes and tested for Cr (VI) reduction, and found that NahG reduced 79% of 100 μM Cr (VI) in 5 minutes. Additionally, an nahG deletion mutant lost 52% of its Cr (VI) reduction ability compared to that of the wild-type strain. As nahG encodes a salicylate hydroxylase with flavin adenine dinucleotide (FAD) as a cofactor for electron transfer, Cr (VI) could obtain electrons from NADH through NahG-associated FAD. To the best of our knowledge, this is the first report of a protein involved in a PAH-degradation pathway that can reduce heavy metals, which provides new insights into heavy metal-PAH contamination remediation.
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CRYSTENGCOMM
·
2017
·Vol. 19
·期 37
·5686-5691
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IF 3.474
Zhao Huang,Kai Cai,Huan Zhang,Zilan Hong,Zhaodong Yuan,Heyou Han
A facile method for the synthesis of Au-pearl/Pd-wire heterostructured nanonecklaces (APHNs) was developed for the first time, in which regular Au pearls with controllable size and interval distance were interlinked into a string by an ultrathin and ultralong Pd nanowire. The distribution density of Au nanopearls was regulated by the concentration of the reducing agent, while their size was controlled by the amount of the Au precursor. In the study of degradation of 4-nitrophenol (4-NP), the catalytic properties of several typical APHNs are proved to be inherently related to their morphology. By comparison with other nanostructures and commercial Pd/C, the APHNs show superior catalytic activities and better stability in general. The study demonstrated that novel heterostructures have superior catalytic properties in the degradation of 4-NP. Moreover, the nanostructures have the potential to be used as a high-efficiency catalyst in other catalytic reactions.
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COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
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IF 4.9
Tingting Li,Yukun An,Jiashuang Li,Zhiming Zhang,Lin Liu,Libao An
A bimetallic Ln-MOF nanofibrous membrane (NFM) was successfully fabricated by in situ growth of Eu/Tb-MOF crystals onto electrospun polycaprolactam (PA6) nanofibers . For better combining with PA6 nanofibers , the Eu/Tb-MOFs were made into nanocrystals . Characterization with PXRD , FT-IR, EDS and XPS confirmed that the crystal structure of the Eu/Tb-MOFs maintained well on PA6 NFM. The as-prepared Eu/Tb-MOF@PA6 NFM can be used as a colorimetric fluorescent test strip for instant detection of the volume ratio of 1, 4-dioxane in 1, 4-dioxane-glycol mixture. With the increase of 1, 4-dioxane, the test strip presented color changes from green to red, which can be easily distinguished by the naked eye. In view of this, the conversion rate of the condensation reaction of glycol to 1, 4-dioxane will be preliminarily estimated without the help of equipment. More importantly, the test strip exhibited better convenience and reversibility compared with powdered Ln-MOFs because no separation process was needed for test strip before and after recovering. Benefiting from sufficient amide groups in PA6 for anchoring Eu/Tb-MOF particles, the test strip showed satisfactory stability in cycling experiments. This work will provide a new insight into the development of fluorescent test strip based on electrospun MOF NFM for quantitatively monitoring the reaction process.
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ACS Applied Nano Materials
·
2024
·
IF 5.3
Qingqing Liu,Xin Deng,Lihua Zhu,Ping Huang,Weizhen Wang,Liqing Li,Zhiqing Yang,Huan Zhang,Junyuan Xu,Hengqiang Ye
To obtain a recyclable and environmentally friendly solid catalyst with excellent catalytic properties and selectivity for 4-nitrophenol (4-NP) hydrogenation, herein, covalent organic frameworks (COFs) are used as the support. Tiny PdCo alloy particles are confined in the pores of the COFs to acquire PdCo/COFs, with an extremely narrow PtCo size distribution (6.28 ± 2.85 nm). The effect of Pd+Co loading and the Pd/Co atomic ratio on the catalytic behaviors of PdCo/COFs for 4-NP hydrogenation is explored. The as-gained PdCo/COFs catalyst (Pd─1.72, Co─1.23 wt %) exhibits good catalytic behaviors (conversion─90.5%, selectivity to 4-aminophenol (4-AP) > 99.0%, and conversion─11.0%, selectivity to 4-aminophenol (4-AP) > 99.0%, TOF─turnover frequency─44.2 min–1) for 4-NP hydrogenation under quite moderate reaction conditions (40 °C, 3.0 MPa hydrogen pressure), and PdCo/COFs have superior stability. Additionally, the catalytic property of PdCo/COFs is better than that of monometallic supported catalysts (Pd/COFs or Co/COFs) and PdNi/COFs. It can be considered that the formation of the PdCo alloy particles is beneficial to the activation of 4-NP. The PdCo/COFs catalysts are analyzed by XRD, XPS, ICP-OES, SEM-EDX, BET, TEM, HRTEM, STEM-EDX elemental analysis, and aberration-corrected STEM (AC-STEM), confirming that tiny PdCo alloy particles are uniformly loaded on the COFs. The PdCo/COFs samples have the advantages of outstanding stability and thus their own desired industrial application potential.
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JOURNAL OF ETHNOPHARMACOLOGY
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2015
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IF 2.998
Hui-Hui Xiao,Quan-Gui Gao,Ming-Xian Ho,Yan Zhang,Ka-Chun Wong,Yi Dai,Xin-Sheng Yao,Man-Sau Wong
Ethnopharmacological relevance Sambucus williamsii Hance (SWH), which belongs to the Caprifoliaceae family distributed in various regions of China, Korea and Japan, has been used as a folk medicine for treatment of bone and joint diseases in China for thousands of years. In previous studies, SWH was shown to possess anti-osteoporosis, healing fracture, anti-inflammatory and analgesic activities. Our previous studies showed that SWH extract effectively suppressed ovariectomy-induced increase in bone turnover and improved bone mineral density and bone biomechanical strength in rats as well as in mice. An 8- O -4′ norlignan, (7 R ,8 S )-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-1,3-propanediol (PPD) was previously isolated and identified as the bioactive ingredient in SWH. The present study aimed to characterize the bone protective effects as well as its mechanism of actions in osteoblasts. Materials and methods Bone protective actions of PPD on different cells were determined by proliferation assay, alkaline phosphatase (ALP) activity assay, calcium deposition as well as real-time reverse transcriptase-polymerase chain reaction (RT-PCR). In addition, estrogen receptor (ER) antagonist ICI182,780 and mitogen-activated protein kinase kinase (MEK) inhibitor U0126 blocking assays, competitive ER radioligand binding assay, ERE-dependent luciferase reporter assay and immunoblotting were used to determine if PPD activated ER and if the effects of PPD on osteoblastic functions were ER dependent. Results PPD exerted anabolic effects in osteoblasts and its effects were abolished by co-incubation with ICI182,780 or U0126. PPD induced mRNA expressions of Runx2, ALP, osteocalcin, and increased the ratio of osteoprotegerin/receptor activator of nuclear factor κB (OPG/RANKL). PPD failed to bind to either ERα or ERβ and did not activate ERE-luciferase activity via ER. PPD induced the phosphorylation of extracellular regulated kinases (ERK) and its effect was completely abolished by U0126. It also induced the phosphorylation of ERα at serine 118. Conclusion These data show that PPD is a bioactive compound in SWH that exerts oestrogen-like actions in osteoblast-like cells via ligand-independent, estrogen response element (ERE)-independent and mitogen-activated protein (MAP) Kinase-mediated rapid nongenomic ER signaling pathway.
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Analytical Methods
·
2017
·Vol. 9
·期 17
·2517-2522
·
IF 1.9
Chenmeng Zhang,Xiu Liang,Tingting You,Nan Yang,Yukun Gao,Penggang Yin
An ultrasensitive “turn off” Surface Enhanced Raman Spectroscopy (SERS) sensor was developed for the detection of heparin based on the anti-aggregation of 4-mercaptobenzoic acid stabilized gold nanoparticles. In this paper, protamine, a small protein molecule with positive charges, could induce the aggregation of 4-MBA functionalized gold nanoparticles via surface electrostatic interaction. However, in the presence of heparin, the aggregation of 4-MBA functionalized gold nanoparticles decreased due to the fact that heparin has a strong affinity toward protamine, further causing the loss of the Raman enhanced effect. The normalized SERS intensity of the Raman reporter was proportional to the concentration of added heparin and a good linear detection range was obtained from 0.05 to 20 ng mL−1 (R2 = 0.999) with a calculated detection limit of 0.03 ng mL−1. Moreover, the developed highly selective method is also successfully demonstrated in fetal bovine serum. Our method is specific, simple and cheap, which could be applied to other further research studies of heparin.
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JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2016
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IF 3.652
Qiang Lu,Zhi-bo Zhang,Xiao-ning Ye,Wen-tao Li,Bin Hu,Chang-qing Dong,Yong-ping Yang
A new technique was proposed to selectively produce 4-ethyl guaiacol (4-EG), a valuable phenolic compound, via low-temperature catalytic fast pyrolysis of softwood biomass using the Pd/SBA-15 catalyst. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) experiments were performed to compare 4-EG production from three biomass materials with different lignin types (pine wood, poplar wood and bagasse) and two catalytic patterns (in-situ and ex-situ). Further experiments were performed to reveal 4-EG formation affected by the pyrolysis temperature, catalyst-to-biomass ratio and Pd content of the Pd/SBA-15 catalyst. The results indicated that 4-EG could be selectively produced from pine wood by the in-situ catalytic pattern. 4-EG was a very minor pyrolytic product in the non-catalytic process, while it could be selectively produced in the catalytic process, via the decomposition and hydrogenation of lignin. Our results suggested that several holocellulose-derived pyrolytic products could serve as the hydrogen-donors (H-donors) for the formation of 4-EG, without any extra H-donors. The highest 4-EG yield of 18.44 mg/g from pine wood was obtained at the temperature of 350 °C and catalyst-to-biomass ratio of 2, and the corresponding peak area% (calculated by GC/MS) was 38.34%.
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ANALYTICAL SCIENCES
·
2017
·Vol. 33
·期 7
·793-799
·
IF 1.228
Wang Yan,Huang Bin-Bin,Dai Wan-Lin,Xu Bin,Wu Tian-Liang,Ye Jia-Ping,Ye Jian-Shan
A sensitive capsaicin sensor was constructed based on a poly(sodium 4-styrenesulfonate) functionalized graphite modified screen printed electrode (PSS-Grp/SPE) in this study. The PSS-Grp and poly(diallyldimethylammonium chloride) functionalized graphite (PDDA-Grp) were easily synthesized by interacting Grp with PSS and PDDA through sonication, and resulted in negative and with positive charges on the surface, respectively. The prepared PSS-Grp and PDDA-Grp were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and ultraviolet and visible spectroscopy (UV-vis). The electrochemical performance of PSS-Grp in a 50 μM capsaicin solution presented a current density of 33 μA cm –2 , which was much higher than the PDDA-Grp of 1.5 μA cm –2 . Our study showed that capsaicin could interact better with strong negative charges on the PSS-Grp/SPE surface to give a higher electrochemical response. The direct electrochemical sensing of capsaicin was achieved at PSS-Grp/SPE using differential pulse stripping voltammetry (DPSV) under the optimized conditions.
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