Journal of Environmental Sciences
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2019
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IF 3.556
Li Long,Xiaolan Hu,Jinpeng Yan,Yifan Zeng,Jiaqi Zhang,Yingwen Xue
It is urgent to explore an effective removal method for perfluorooctanoic acid (PFOA) due to its recalcitrant nature. In this study, a novel chitosan-based hydrogel (CEGH) was prepared with a simple method using chitosan and ethylene glycol through a repeated freezing–thawing procedure. The adsorption of PFOA anions to CEGH agreed well to the Freundlich–Langmuir model with a maximum adsorption capacity as high as 1275.9 mg/g, which is higher than reported values of most adsorbents for PFOA. The adsorption was influenced by experimental conditions. Experimental results showed that the main removal mechanism was the ionic hydrogen bond interaction between carbonyl groups (COO − ) of PFOA and protonated amine (NH + ) of the CEGH adsorbent. Therefore, CEGH is a very attractive adsorbent that can be used to remove PFOA from water in the future.
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CARBOHYDRATE POLYMERS
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2019
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IF 6.044
Shangpeng Liu,Zhiqin Zheng,Shuang Wang,Shaojuan Chen,Jianwei Ma,Guosai Liu,Bin Wang,Jiwei Li
In this study, polydopamine (PDA) coated chitosan/calcium pyrophosphate hybrid microflowers (PDA@CS-CaP) were prepared using a facile approach and evaluated as a hemostatic agent. The surface morphology and elements, chemical groups, porous structure, thermostability, zeta potential, as well as surface wettability were systematically characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), N 2 adsorption-desorption, thermogravimetry (TGA) and contact angle apparatus. Due to the synergistic effects of the high hydrophilicity (water contact angel nearly 0), chemical activation (the amino and phenol group of PDA), and the flower-like porous hierarchical structure, the prepared PDA@CS-CaP could induce hemocytes and platelets aggregation, promote the blood clotting and achieve bleeding control in vitro and in vivo. Furthermore, the PDA@CS-CaP had no exothermic adverse effects and exhibited better biocompatibility (no cytotoxicity against fibroblasts cells). Thus, the PDA@CS-CaP were expected to be a promising candidate for a safe and promising hemostatic agent because of its porous and hierarchical structures as well as the active PDA coating.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2019
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IF 4.784
Govindan Rajivgandhi,Muthuchamy Maruthupandy,Thangasamy Veeramani,Franck Quero,Wen-Jun Li
In the present investigation functional chitosan/silver nanocomposites (CS/Ag NCs) were successfully synthesized and found to possess favorable antibacterial activity against extended spectrum beta-lactasame (ESBL) producing Pseudomonas aeruginosa . Powder X-ray diffraction showed that the obtained CS/Ag NCs are constituted of highly crystalline Ag nanoparticles (NPs) embedded in an amorphous CS matrix material. Transmission electron microscopy (TEM) analysis provided structural information about CS/Ag NCs, revealing the formation of spherical cluster structures constituted of Ag NPs with size ranging from 6 to 18 nm embedded in the amorphous CS matrix. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Ag NPs and CS/Ag NCs were found to inhibit the ESBL producing P. aeruginosa at 80 μg/mL (76%) and 50 μg/mL (92%), respectively. Confocal laser scanning microscope (CLSM) and scanning electron microscopy (SEM) images revealed that P. aeruginosa experienced reduced cell viability and morphological cell membrane damage at desired MIC. The in-vivo toxicity effect of Ag NPs and CS/Ag NCs suggested an increased mortality rate when Artemia franciscana were exposed for 24 h to increasing concentrations of Ag NPs and CS/Ag NCs. Anti-ESBL activity and toxicity effect of CS/Ag NCs revealed that these NCs possess promising antibacterial properties to overcome numerous communicable bacterial strains .
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EUROPEAN POLYMER JOURNAL
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2019
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IF 3.621
Shubo Wang,Lei Shi,Shuo Zhang,Hang Wang,Bowen Cheng,Xupin Zhuang,Zhenhuan Li
Proton transfer using amino acids as proton delivery sites is a ubiquitous and important process in organisms. In this study, novel proton-conducting nanofibers were prepared on the basis of a bionic design concept from two perspectives, namely, proton transfer site and proton transfer route, by immobilizing four kinds of amino acids, namely, serine, arginine, lysine, and glycine, onto chitosan (CS) nanofibers. Nanocomposite membranes were then fabricated by filling the pores of the amino acid-functionalized CS nanofiber mats (AA-CSNFs) with sulfonated polysulfone (SPSF). The methanol crossover of the nanocomposite membranes with AA-CSNFs was reduced and their proton conductivity was increased compared with those of pure SPSF membrane. The nanocomposite membrane embedded with the serine-functionalized CS nanofibers exhibited an excellent proton-conducting ability with the highest proton conductivity of 0.192 S/cm at 80 °C. Results indicated that these nanocomposite membranes showed potential for applications in proton exchange membrane fuel cells with superior combined properties.
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Materials Science & Engineering C-Materials for Biological Applications
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2019
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IF 4.959
Xinchen Du,Yujie Liu,Xin Wang,Hongyu Yan,Lina Wang,Lijie Qu,Deling Kong,Mingqiang Qiao,Lianyong Wang
An injectable hydrogel dressing with multifunctional properties of superior hemostasis, antibacterial activity, tissue adhesive and cytocompatibility is desirable candidate in wound healing. In this study, we developed a novel hydrogel dressing composed of hydrophobically modified chitosan (hmCS) and oxidized dextran (OD). The gelation time, microstructure, injectability, self-healing and rheological properties were characterized. The in vitro ability of the precursor solution of the hydrogels to coagulate heparinized whole blood was confirmed. The in vivo hemostatic activity was demonstrated in a rat hemorrhaging liver model. The antibacterial activity against S. aureus and P. aeruginosa was evaluated in vitro through surface antibacterial test. The corresponding killing efficiencies were up to 95.0% and 96.4% at bacterial concentration of 10 8 CFU/mL. The cytotoxicity was examined by co-culturing with 3 T3 fibroblast cells. The wound healing functions were further verified with an infected wound model of rat skin. The aforementioned findings demonstrated that the hydrogel with multifunctional activities has potential for hemorrhagic and infected wound healing.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2020
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IF 5.162
A.A. Menazea,M.M. Eid,M.K. Ahmed
With the increase of antibiotic resistance currently available at an alarming rate, new improved films of Chitosan (CS) have been achieved with different levels of Tigecycline (TIGE) using traditional casting technology. The structural, optical, and morphological characterizations of the prepared (CS/TIGE) composites were investigated using XRD, FT-IR, UV–visible, and FE-SEM. Also, the antibacterial characterization was investigated. XRD pattern shows a semi-crystalline peak at 2θ = 21° begins to appear at Cs/TIGE2 concentration and its intensity increase with increasing TIGE concentration which indicate the interaction between TIGE and Cs. FT-IR reveals conservation of the distinctive bands with change in both intensity and position that attributed to increase the ratios of TIGE in Chitosan. UV–vis spectra confirmed the interaction of the CS and the drug TIGE. FE-SEM photos confirm the increasing of TIGE particles on the surface of CS/TIGE films by increasing the ratios of TIGE. The antimicrobial effect of Chitosan and five different ratios of Chitosan with TIGE have been identified against four different bacterial species, two gram-negative ( Escherichia coli , Bacillus subtilis) and two gram-positive bacteria ( Staphylococcus aureus , Pseudomonas aeruginosa ). The obtained results indicated that the composite Cs/TIGE can be used in many antimicrobial applications because of its greatly antimicrobial activity .
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COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2020
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IF 3.99
Ping Tan,Yixi Zheng,Yongyou Hu
A novel adsorbent CSN-La of lanthanum immobilized on electrospun chitosan nanofiber(CSN) was fabricated and used as adsorbent for arsenate removal. The effects of pH, contact time, arsenate concentration as well as column adsorption were investigated. The results indicated that the arsenate adsorption by CSN-La was pH dependent. The experimental data of arsenic adsorption by CSN-La well fitted pseudo-second-order kinetic model and Langmuir model. The saturated adsorption capacity of CSN-La reached up to 83.6 mg/g, which was significantly higher than that of CSN . CSN-La exhibited preferable arsenate removal in the presence of coexisting anions (chloride, sulfate, nitrate, bicarbonate) at much greater levels. The attractive performance of CSN-La rooted from its special structural characteristics, the host material CSN favored the preconcentration of arsenate through electrostatic attraction, and the immobilized lanthanum exhibited preferable arsenate removal through specific interaction. Column adsorption run by using CSN-La could effectively treat approximately 2650 bed volumes (BV) of feeding solution before breakthrough occurred (from 210 μg/L in influent to < 10 μg/L in effluent). The exhausted CSN-La could be repeatedly used after being eluted by sodium hydroxide solution. The obtained results indicated that CSN-La has a great potential in efficient removal of arsenate-containing water.
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CARBOHYDRATE POLYMERS
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2019
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IF 6.044
Yueying Wang,Minhao Xie,Gaoxing Ma,Yong Fang,Wenjian Yang,Ning Ma,Donglu Fang,Qiuhui Hu,Fei Pei
Four phenolic acid-grafted-chitosan conjugates were prepared with different phenolic acids including gallic acid (GLA), caffeic acid (CA), gentisate acid (GTA) and sinapic acid (SA), and their characteristics were analyzed. Furthermore, the antioxidant and antimicrobial activities of conjugates were compared to screen out the optimal conjugates. The characterization analysis showed that the UV absorption peaks of CA-g-CS were stronger than that of GLA-g-CS, indicating a higher substitution degree. In addition, the substitution degree and antioxidant activity of caffeic acid-grafted-chitosan (CA-g-CS) and gallic acid-grafted-chitosan (GLA-g-CS) had significantly ( p < 0.05) higher than CS and other two conjugates. However, CA-g-CS demonstrated stronger bacteriostatic ability, of which the minimum inhibitory concentrations (MICs) against Pseudomonas aeruginosa , Escherichia coli , Bacillus subtilis and Staphylococcus aureus were lower, and the inhibitory zones were larger than GLA-g-CS. In summary, the present findings will provide a theoretical basis for the expanding of CS application in food processing and preservation.
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INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2018
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IF 3.141
Yun Liao,Meng Wang,Dajun Chen
The relatively low density of functional groups of graphene oxide (GO) and the difficulty to completely recover after adsorption limit its application in uranium (U(VI)) removal from aqueous solution. Inspired by a special chemical property, polydopamine (PDA) was first used as a surface modifying agent for GO, and then the as-formed GO@PDA cross-linked with chitosan (CS) to assemble a three-dimensional (3D) porous GO@PDA/CS aerogel for U(VI) adsorption. Morphology and structure of the aerogel were characterized by TEM, SEM, FTIR, XPS, XRD, Raman, and TGA. The results show that compared to GO/CS, the GO@PDA/CS aerogel possesses a more homogeneous and well-organized 3D porous structure as well as the enhanced active sites, which are beneficial for U(VI) removal. According to batch experiments, the adsorption rate of the GO@PDA/CS aerogel was very fast, and the adsorption equilibrium could be reached in 15 min at pH = 6.0. Its maximum adsorption capacity for U(VI) is as high as 415.9 mg g–1 at 298 K calculated from the Langmuir model. In addition, the as-prepared GO@PDA/CS aerogel exhibits satisfactory thermal and mechanical stability and could be recycled six times without an apparent decrease in removal efficiency.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2018
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IF 3.909
Enhui Zhang,Ronge Xing,Song Liu,Kecheng Li,Yukun Qin,Huahua Yu,Pengcheng Li
A gastric cancer angiogenesis marker peptide, GX1, is promising to be a desirable ligand for anti-angiogenesis targeted drug of gastric cancer treatment. In this study, GX1 was utilized to fabricate a multifunctional vascular targeting docetaxel (DCT)-loaded nanoparticle with N -deoxycholic acid glycol chitosan (DGC) as the carrier and GX1-PEG-deoxycholic acid (GPD) conjugate as the targeting ligand. The mean size of obtained GX1-DGC-DCT was 150.9 nm with a narrow size distribution and their shape was spherical with smooth surface texture. The in vitro drug release test revealed a sustained release manner and an acid pH could accelerate the release compared with the neutral pH. Furthermore, GX1-DGC-DCT showed stronger cytotoxicity against co-cultured gastric cancer cells and human umbilical vein endothelial cells (co-HUVEC) than DCT within 100 μM. In addition, GX1 efficiently enhanced the cellular uptake of nanoparticles in co-HUVEC cells as confirmed by confocal fluorescence scanning microscopy. Moreover, in vivo delivery of GX1-DGC-DCT was demonstrated to inhibit tumor growth in SGC791 tumor-bearing mice with tumor inhibition rate (TIR) of 67.05% and no weight loss of mice was observed. The anti-tumor effects were further confirmed by H&E and TUNEL analysis. Therefore, this new drug delivery system represents a potential strategy for gastric cancer therapy.
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CARBOHYDRATE POLYMERS
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2018
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IF 5.158
Xiaonan Huo,Wei Li,Yu Wang,Na Han,Jianping Wang,Ning Wang,Xingxiang Zhang
In order to reduce environmental pollution during microencapsulating phase change materials and expand their applications as well, a novel eco-friendly microencapsulated/nanoencapsulated phase change materials (Micro/NanoPCMs) and the corresponding encapsulation method were proposed and discussed in this study, where the natural chitosan and side-chain crystallizable comb-like polymer were selected as shell material and core material, respectively. During the encapsulating process via coacervation, the effects of different core-shell ratios on the morphology and thermal storage properties of microcapsules were discussed. FE-SEM and TEM was employed to investigate the morphology and microstructure of the microcapsules. The thermodynamics performance of microcapsules was studied using TGA and DSC. The encapsulation efficiency of microcapsules ranged from 49.82% to 68.99%, and the thermal stability temperature of microcapsules was measured to be 243.2 °C. The fabrication process where natural raw materials were employed and showing promising applications in such fields as medical treatment.
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JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY
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2018
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IF 2.297
Chao Luo,Weibin Wu,Xinyu Lin,Yaoqi Li,Kai Yang
The objective of this study was to develop and evaluate a novel tanshinone IIA (TA)/chitosan (CS) solid dispersion (TA-CS-SD) to improve the bioavailability. Solid dispersion of tanshinone IIA with chitosan was prepared by a pH inversion method via the pH-responsive dissolution property of chitosan matrix. The in vitro dissolution study confirmed dramatically elevated dissolution rate of TA by solid dispersion approach, and the release mechanism exhibited pH-responsive performance. The solid dispersion was characterized by x-ray diffractometry (XRD), differential scanning calorimetry (DSC), fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Our results showed that TA existed in the form of microcrystal or superfine crystal in solid dispersion, and the reduction of crystallinity was correlated with the content of CS matrix. In vitro cytotoxicity study was performed in human non-small cell lung cancer A549 cell line by CCK-8 assay. Significant improvement in antitumor activity of TA in TA-CS-SD was achieved compared to the crystalline drug. These results indicated that, compared with free TA, TA-CS-SD demonstrated higher dissolution rate and bioactivity.
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