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Jun Nie - One of the best experts on this subject based on the ideXlab platform.
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Preparation and properties of photo-crosslinkable hydrogel based on photopolymerizable Chitosan Derivative.
International journal of biological macromolecules, 2012Co-Authors: Zhiliang Wang, Jun NieAbstract:Abstract Photopolymerizable Chitosan Derivative was synthesized by Chitosan and methyl acroloyl glycine (MAG). The chemical structures and physical properties were characterized by FT-IR, 1 H NMR, XRD and TGA. The thermal stability of Chitosan Derivative was lower than Chitosan. The Chitosan Derivative was amorphous compared with the high degree crystallization of Chitosan. The hydrogels were prepared based on Chitosan Derivative via photopolymerization with different concentrations of photoinitiator 2959. The surface of hydrogel showed porous network and the pore size distribution tended to become homogeneous with the increase of the concentration of 2959, while the swelling property decreased due to more crosslinking.
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Synthesize and properties of photosensitive organic solvent soluble acylated Chitosan Derivatives (2)
Carbohydrate Polymers, 2011Co-Authors: Yang Liu, John F. Kennedy, Jun NieAbstract:Abstract A Chitosan Derivative carrying the benzene group was synthesized by the acylation reaction in the mild conditions. The chemical structures and physical properties of the compounds were characterized in detail. The Chitosan Derivatives were amorphous comparing with Chitosan. The photopolymerization capability of Chitosan Derivative was also carried out by real-time infrared (RTIR) spectra, and it also has the own ability to photopolymer without photoinitiator under UV irradiation. The Derivative had good ultraviolet absorption at 280 nm and good solubility in organic solvents.
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Preparation and characterization of water-soluble Chitosan Derivative by Michael addition reaction.
International journal of biological macromolecules, 2010Co-Authors: Mingyan Jiang, Kemin Wang, John F. Kennedy, Jun NieAbstract:The efficient procedure to prepare novel water-soluble Chitosan Derivative was established by Michael addition reaction to introduce sodium allylsulfonate into the Chitosan at mild condition. The chemical structure of the Chitosan Derivative was characterized by FT-IR, (1)H NMR and Elemental analysis. The degree of substitution (DS) was calculated by Elemental analysis. The Chitosan Derivative exhibited an excellent solubility in the distilled water. The physical properties were analyzed by XRD and TG. The XRD study indicated that the crystallinity of Chitosan Derivative decreased. The thermal analysis showed that Chitosan Derivative had lower thermal stability than Chitosan.
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Synthesis and properties of photosensitive Chitosan Derivatives(1)
International journal of biological macromolecules, 2010Co-Authors: Bin Qian, Jianxin Yang, Jun NieAbstract:Abstract A novel Chitosan Derivative carrying the benzene group was synthesized by Michael reaction. The chemical structures of the compounds were characterized by FT-IR, UV–vis spectrometry, XRD, elemental analysis, and 1 H NMR spectroscopy in detail. The degree of substitution (DS) of Chitosan Derivative was calculated by elemental analysis. The UV–vis results indicated that the Derivatives had ultraviolet absorption at 265 and 273 nm. XRD analysis showed that the Derivatives were amorphous. The Derivatives could dissolve in water. Taking advantage of the known capacity of solubility and ultraviolet absorption, the Chitosan Derivatives opened new possibilities for use as a sunscreen.
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injectable hydrogels based on Chitosan Derivative polyethylene glycol dimethacrylate n n dimethylacrylamide as bone tissue engineering matrix
Carbohydrate Polymers, 2010Co-Authors: Dongzhi Yang, Kemin Wang, Binling Chen, John F. Kennedy, Jun NieAbstract:Abstract Injectable hydrogels were prepared from Chitosan Derivative (EGAMA-CS) / polyethylene glycol dimethacrylate (PEGDA)/ N , N -dimethylacrylamide (DMMA) by photopolymerization. The morphology of the hydrogels was observed by scanning electron microscope (SEM). The relationship of double bond conversion with photopolymerization time was revealed by Real-time FTIR. The thermal behaviour of the hydrogels was investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The equilibrium swelling ratio was also evaluated. In addition, the potential use of the hydrogels as scaffolding materials for bone regeneration was evaluated in vitro with Human bone sarcoma cell (SW1353) as reference cell lines. Indirect cytotoxicity assessment of the hydrogels indicated that the EGAMA-CS / PEGDA / DMMA hydrogels was non-toxic to the SW1353 cell. Cell culture results showed that fibrous mats were good in promoting the cell attachment and proliferation. The photopolymerized hydrogels are promised for the applications in the biomaterials area as bone tissue engineering matrix.
Samuel M Hudson - One of the best experts on this subject based on the ideXlab platform.
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application of a fiber reactive Chitosan Derivative to cotton fabric as an antimicrobial textile finish
Carbohydrate Polymers, 2004Co-Authors: Samuel M HudsonAbstract:A fiber-reactive Chitosan Derivative, O-acrylamidomethyl-N-[(2-hydroxy-3-trimethylammonium)propyl] Chitosan chloride (NMA-HTCC), was applied to cotton fabrics by a cold pad-batch method in the presence of an alkaline catalyst to evaluate its use as a durable antimicrobial textile finish. The antimicrobial activities of the NMA-HTCC treated cotton fabrics were evaluated quantitatively against Staphylococcus aureus. The cotton treated with NMA-HTCC at a concentration of 1% on weight of fabric showed 100% of bacterial reduction. The activity was maintained over 99% even after being exposed to 50 consecutive home laundering condition. The effect of an anionic surfactant on the antimicrobial activity of the NMA-HTCC treated fabric was discussed.
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synthesis and antimicrobial activity of a water soluble Chitosan Derivative with a fiber reactive group
Carbohydrate Research, 2004Co-Authors: Sanghoon Lim, Samuel M HudsonAbstract:Abstract A novel fiber-reactive Chitosan Derivative was synthesized in two steps from a Chitosan of low molecular weight and low degree of acetylation. First, a water-soluble Chitosan Derivative, N -[(2-hydroxy-3-trimethylammonium)propyl]Chitosan chloride (HTCC), was prepared by introducing quaternary ammonium salt groups on the amino groups of Chitosan. This Derivative was further modified by introducing functional (acrylamidomethyl) groups, which can form covalent bonds with cellulose under alkaline conditions, on the primary alcohol groups (C-6) of the Chitosan backbone. The fiber-reactive Chitosan Derivative, O -acrylamidomethyl-HTCC (NMA–HTCC), showed complete bacterial reduction within 20 min at the concentration of 10 ppm, when contacted with Staphylococcus aureus and Escherichia coli (1.5–2.5 × 10 5 colony forming units per milliliter [CFU/mL]).
John F. Kennedy - One of the best experts on this subject based on the ideXlab platform.
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Synthesize and properties of photosensitive organic solvent soluble acylated Chitosan Derivatives (2)
Carbohydrate Polymers, 2011Co-Authors: Yang Liu, John F. Kennedy, Jun NieAbstract:Abstract A Chitosan Derivative carrying the benzene group was synthesized by the acylation reaction in the mild conditions. The chemical structures and physical properties of the compounds were characterized in detail. The Chitosan Derivatives were amorphous comparing with Chitosan. The photopolymerization capability of Chitosan Derivative was also carried out by real-time infrared (RTIR) spectra, and it also has the own ability to photopolymer without photoinitiator under UV irradiation. The Derivative had good ultraviolet absorption at 280 nm and good solubility in organic solvents.
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Preparation and characterization of water-soluble Chitosan Derivative by Michael addition reaction.
International journal of biological macromolecules, 2010Co-Authors: Mingyan Jiang, Kemin Wang, John F. Kennedy, Jun NieAbstract:The efficient procedure to prepare novel water-soluble Chitosan Derivative was established by Michael addition reaction to introduce sodium allylsulfonate into the Chitosan at mild condition. The chemical structure of the Chitosan Derivative was characterized by FT-IR, (1)H NMR and Elemental analysis. The degree of substitution (DS) was calculated by Elemental analysis. The Chitosan Derivative exhibited an excellent solubility in the distilled water. The physical properties were analyzed by XRD and TG. The XRD study indicated that the crystallinity of Chitosan Derivative decreased. The thermal analysis showed that Chitosan Derivative had lower thermal stability than Chitosan.
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injectable hydrogels based on Chitosan Derivative polyethylene glycol dimethacrylate n n dimethylacrylamide as bone tissue engineering matrix
Carbohydrate Polymers, 2010Co-Authors: Dongzhi Yang, Kemin Wang, Binling Chen, John F. Kennedy, Jun NieAbstract:Abstract Injectable hydrogels were prepared from Chitosan Derivative (EGAMA-CS) / polyethylene glycol dimethacrylate (PEGDA)/ N , N -dimethylacrylamide (DMMA) by photopolymerization. The morphology of the hydrogels was observed by scanning electron microscope (SEM). The relationship of double bond conversion with photopolymerization time was revealed by Real-time FTIR. The thermal behaviour of the hydrogels was investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The equilibrium swelling ratio was also evaluated. In addition, the potential use of the hydrogels as scaffolding materials for bone regeneration was evaluated in vitro with Human bone sarcoma cell (SW1353) as reference cell lines. Indirect cytotoxicity assessment of the hydrogels indicated that the EGAMA-CS / PEGDA / DMMA hydrogels was non-toxic to the SW1353 cell. Cell culture results showed that fibrous mats were good in promoting the cell attachment and proliferation. The photopolymerized hydrogels are promised for the applications in the biomaterials area as bone tissue engineering matrix.
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Injectable hydrogels based on Chitosan Derivative/polyethylene glycol dimethacrylate/N,N-dimethylacrylamide as bone tissue engineering matrix
Carbohydrate Polymers, 2010Co-Authors: Dongzhi Yang, Kemin Wang, Binling Chen, John F. Kennedy, Jun NieAbstract:Abstract Injectable hydrogels were prepared from Chitosan Derivative (EGAMA-CS) / polyethylene glycol dimethacrylate (PEGDA)/ N , N -dimethylacrylamide (DMMA) by photopolymerization. The morphology of the hydrogels was observed by scanning electron microscope (SEM). The relationship of double bond conversion with photopolymerization time was revealed by Real-time FTIR. The thermal behaviour of the hydrogels was investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The equilibrium swelling ratio was also evaluated. In addition, the potential use of the hydrogels as scaffolding materials for bone regeneration was evaluated in vitro with Human bone sarcoma cell (SW1353) as reference cell lines. Indirect cytotoxicity assessment of the hydrogels indicated that the EGAMA-CS / PEGDA / DMMA hydrogels was non-toxic to the SW1353 cell. Cell culture results showed that fibrous mats were good in promoting the cell attachment and proliferation. The photopolymerized hydrogels are promised for the applications in the biomaterials area as bone tissue engineering matrix.
Zhanyong Guo - One of the best experts on this subject based on the ideXlab platform.
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enhanced antifungal activity of novel cationic Chitosan Derivative bearing triphenylphosphonium salt via azide alkyne click reaction
International Journal of Biological Macromolecules, 2020Co-Authors: Wenqiang Tan, Jingjing Zhang, Fang Dong, Zhanyong GuoAbstract:Abstract As one of the most promising biopolymers for a variety of potential applications, Chitosan has attracted much attention because of its unique biological, chemical, and physical properties. The functionalization of Chitosan has been adopted to synthesize novel Chitosan Derivatives with improved water-solubility and excellent biological activities. In this paper, Chitosan was functionalized with a triphenylphosphonium group by means of the copper (I) catalyzed azide-alkyne “click” reaction and has been investigated as potential polymer for agricultural antifungal biomaterial. The influence of chemical modification on the structural characteristics and water-solubility of Chitosan was investigated by FTIR spectroscopy, 1H NMR spectroscopy, elemental analysis, and UV–vis spectrum. Furthermore, the antifungal property of target Chitosan Derivative against four plant threatening fungal pathogens was evaluated and in vitro investigation demonstrated that triphenylphosphonium salt incorporated Chitosan backbone had excellent antifungal property compared with Chitosan and intermediate Chitosan Derivative. Notably, target Chitosan Derivative displayed relatively strongest antifungal effect with over 80% inhibitory index against Botrytis cinerea at 1.0 mg/mL. The results of a detailed antifungal study indicated that cationic Chitosan Derivative bearing 1,2,3-triazole and triphenylphosphonium moieties provided a promising platform for preparation of novel cationic antifungal biomaterials in the field of agriculture.
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synthesis characterization and evaluation of antifungal and antioxidant properties of cationic Chitosan Derivative via azide alkyne click reaction
International Journal of Biological Macromolecules, 2018Co-Authors: Wenqiang Tan, Jingjing Zhang, Fang Dong, Zhanyong GuoAbstract:Abstract In this work, quaternary ammonium group was introduced into Chitosan backbone by cuprous-catalyzed azide-alkyne cycloaddition (CuAAC) to synthesize the cationic Chitosan Derivative bearing 1,2,3-triazole. The products were identified structurally by FTIR, 1H NMR spectroscopy, XRD, and elemental analysis. The water solubility of Chitosan Derivatives at different pH values was determined by a turbidity measurement. The antifungal properties of cationic Chitosan Derivatives against Botryis cinerea, Phomopsis asparagi, Fusarium oxysporum f. sp. niveum, and Fusarium oxysporum f. sp. cucumerium were evaluated using the radial growth assay. Besides, the antioxidant activities of them were also tested by superoxide-radical scavenging and reducing power assays. Compared to Chitosan, cationic Chitosan Derivative bearing 1,2,3-triazole showed the good water solubility especially at alkaline condition, excellent antifungal action with over 70% inhibitory indices against tested fungi at 1.0 mg/mL, and enhanced antioxidant activity with complete scavenging efficiency against superoxide-radical at 1.6 mg/mL because of the introduction of 1,2,3-triazole and quaternary ammonium moieties. These excellent biological properties present a promising prospect for this Chitosan Derivative in antifungal and antioxidant biomaterials.
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novel cationic Chitosan Derivative bearing 1 2 3 triazolium and pyridinium synthesis characterization and antifungal property
Carbohydrate Polymers, 2018Co-Authors: Wenqiang Tan, Jingjing Zhang, Fang Dong, Fang Luan, Lijie Wei, Yuan Chen, Zhanyong GuoAbstract:Abstract In this paper, novel cationic Chitosan Derivative possessing 1,2,3-triazolium and pyridinium groups was synthesized conveniently via cuprous-catalyzed azide-alkyne cycloaddition (CuAAC) and methylation. FTIR, 1H NMR, and elemental analysis examined the structural characteristics of the synthesized Derivatives. The antifungal efficiencies of Chitosan Derivatives against three plant-threatening fungi were assayed by hypha measurement in vitro. The determination showed that Chitosan Derivative bearing 1,2,3-triazolium and pyridinium displayed tremendously enhanced antifungal activity as compared with Chitosan and Chitosan Derivative bearing 1,2,3-triazole and pyridine. Notably, the inhibitory indices of it against Colletotrichum lagenarium attained 98% above at 1.0 mg/mL. The results showed that N-methylation of 1,2,3-triazole and pyridine could effectively enhance antifungal activity of the synthesized Chitosan Derivatives. Besides, the prepared Chitosan Derivatives showed non-toxic effect on cucumber seedlings. This synthetic strategy might provide an effective way and notion to prepare novel cationic Chitosan antifungal biomaterials.
Dongzhi Yang - One of the best experts on this subject based on the ideXlab platform.
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a water soluble photocrosslinkable Chitosan Derivative prepared by michael addition reaction as a precursor for injectable hydrogel
Carbohydrate Polymers, 2010Co-Authors: Xuanyue Gao, Dongzhi Yang, Yingshan Zhou, Suqing Shi, Jun NieAbstract:Abstract With the goal of obtaining photopolymerized hydrogels for use as tissue engineering scaffolds, a water-soluble (methacryloyloxy) ethyl carboxyethyl Chitosan was prepared as a photopolymerizable prepolymer through Michael-addition reaction between Chitosan and ethylene glycol acrylate methacrylate. N-substitution of Chitosan was verified by both 1 H NMR and 13 C NMR The degree of N-substitution, measured via 1 H NMR, was easily varied from 0.10 to 0.35 by varying the molar ratio of ethylene glycol acrylate methacrylate to Chitosan. Using a Vero cell line, the water-soluble photocrosslinkable Chitosan Derivative was found to be noncytotoxic up to a concentration of 1.0 mg/mL. The precursor was blended with D-2959 photoinitiator in solution, and UV-irradiated to create hydrogels. FTIR verified the nearly complete conversion of the double bonds in the gel. Indirect cytotoxicity assessment of the hydrogel indicated that the hydrogel was non-toxic to Vero cells.
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injectable hydrogels based on Chitosan Derivative polyethylene glycol dimethacrylate n n dimethylacrylamide as bone tissue engineering matrix
Carbohydrate Polymers, 2010Co-Authors: Dongzhi Yang, Kemin Wang, Binling Chen, John F. Kennedy, Jun NieAbstract:Abstract Injectable hydrogels were prepared from Chitosan Derivative (EGAMA-CS) / polyethylene glycol dimethacrylate (PEGDA)/ N , N -dimethylacrylamide (DMMA) by photopolymerization. The morphology of the hydrogels was observed by scanning electron microscope (SEM). The relationship of double bond conversion with photopolymerization time was revealed by Real-time FTIR. The thermal behaviour of the hydrogels was investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The equilibrium swelling ratio was also evaluated. In addition, the potential use of the hydrogels as scaffolding materials for bone regeneration was evaluated in vitro with Human bone sarcoma cell (SW1353) as reference cell lines. Indirect cytotoxicity assessment of the hydrogels indicated that the EGAMA-CS / PEGDA / DMMA hydrogels was non-toxic to the SW1353 cell. Cell culture results showed that fibrous mats were good in promoting the cell attachment and proliferation. The photopolymerized hydrogels are promised for the applications in the biomaterials area as bone tissue engineering matrix.
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Injectable hydrogels based on Chitosan Derivative/polyethylene glycol dimethacrylate/N,N-dimethylacrylamide as bone tissue engineering matrix
Carbohydrate Polymers, 2010Co-Authors: Dongzhi Yang, Kemin Wang, Binling Chen, John F. Kennedy, Jun NieAbstract:Abstract Injectable hydrogels were prepared from Chitosan Derivative (EGAMA-CS) / polyethylene glycol dimethacrylate (PEGDA)/ N , N -dimethylacrylamide (DMMA) by photopolymerization. The morphology of the hydrogels was observed by scanning electron microscope (SEM). The relationship of double bond conversion with photopolymerization time was revealed by Real-time FTIR. The thermal behaviour of the hydrogels was investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The equilibrium swelling ratio was also evaluated. In addition, the potential use of the hydrogels as scaffolding materials for bone regeneration was evaluated in vitro with Human bone sarcoma cell (SW1353) as reference cell lines. Indirect cytotoxicity assessment of the hydrogels indicated that the EGAMA-CS / PEGDA / DMMA hydrogels was non-toxic to the SW1353 cell. Cell culture results showed that fibrous mats were good in promoting the cell attachment and proliferation. The photopolymerized hydrogels are promised for the applications in the biomaterials area as bone tissue engineering matrix.