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Mussel-inspired adhesive antioxidant antibacterial hemostatic composite hydrogel wound dressing via photo-polymerization for infected skin wound healing

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Bioactive Materials 2022年第2期7卷 341-354页

作者： Yutong Yang Yongping Liang Jueying Chen Xianglong Duan Baolin Guo Second Department of General Surgery Shaanxi Provincial People’s HospitalXi’an710068China Frontier Institute of Science and Technology and State Key Laboratory for Mechanical Behavior of Materialsand Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine ResearchCollege of StomatologyXi’an Jiaotong UniversityXi’an710049China Second Department of General Surgery Third Affiliated Hospital of Xi’an Jiaotong UniversityXi’an710068China

With the increasing prevalence of drug-resistant bacterial infections and the slow healing of chronically infected wounds,the development of new antibacterial and accelerated wound healing dressings has become a serious challenge.In order to solve this problem,we developed photo-crosslinked multifunctional antibacterial adhesive anti-oxidant hemostatic hydrogel dressings based on polyethylene glycol monomethyl ether modified glycidyl methacrylate functionalized chitosan(CSG-PEG),methacrylamide dopamine(DMA)and zinc ion for disinfection of drug-resistant bacteria and promoting wound healing.The mechanical properties,rheological properties and morphology of hydrogels were characterized,and the biocompatibility of these hydrogels was studied through cell compatibility and blood compatibility tests.These hydrogels were tested for the in vitro blood-clotting ability of whole blood and showed good hemostatic ability in the mouse liver hemorrhage model and the mouse-tail amputation model.In addition,it has been confirmed that the multifunctional hydrogels have good inherent antibacterial properties against Methicillin-resistant Staphylococcus aureus(MRSA).In the full-thickness skin defect model infected with MRSA,the wound closure ratio,thickness of granulation tissue,number of collagen deposition,regeneration of blood vessels and hair follicles were measured.The inflammation-related cytokines(CD68)and angiogenesis-related cytokines(CD31)expressed during skin regeneration were studied.All results indicate that these multifunctional antibacterial adhesive hemostatic hydrogels have better healing effects than commercially available Tegaderm™Film,revealing that they have become promising alternative in the healing of infected wounds.

关键词： chitosan Wound dressing Antibacterial Wound healing Hemostat Infected skin wound

Effects of chitosan on growth of an aquatic plant (Hydrilla verticillata) in polluted waters with different chemical oxygen demands

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Journal of Environmental Sciences 2007年第2期19卷 217-221页

作者： XU Qiu-jin NIAN Yue-gang JIN Xiang-can YAN Chang-zhou LIU Jin Jiang Gao-ming Lake Research Center Chinese Research Academy of Environmental Sciences Beijing 100012 China Quantitative Vegetation Ecology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

Effects of chitosan on a submersed plant, HydriUa verticillata, were investigated. Results indicated that H. verticillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand （COD）. Superoxide dismutase （SOD） activity and malondialdehyde （MDA） contents in H. verticillata treated with 0.1% chitosan in wastewater increased with high COD （980 rag/L） and decreased with low COD （63 mg/L）, respectively. Ultrastructural analysis showed that the stroma and grana of chloroplast basically remained normal. However, plant ceils from the control experiment （untreated with chitosan） were vacuolated and the cell interval increased. The relict of protoplast moved to the center, with cells tending to disjoint. Our findings indicate that wastewater with high COD concentration can cause a substantial damage to submersed plant, nevertheless, chitosan probably could alleviate the membrane lipid peroxidization and ultrastructure phytotoxicities, and protect plant cells from stress of high COD concentration polluted water.

关键词： antioxdiant enaymes chitosan Hydrilla verticiUata malondialdehyde superoxide dismutase ultrastructure

Relationship between antibacterial activity of chitosan and surface characteristics of cell wall

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Acta Pharmacologica Sinica 2004年第7期25卷 86-90页

作者： Ying-chien CHUNG,Chiing-chang CHEN,Huey-lan WANG,J C Gaston WU,Jaung-geng LIN Fooyin University Kaohsiung 831 China Department of Chemistry National Taiwan Normal University Taipei 116 China Institute of Chinese Medical Science China Medical University Taichung 404 Department of Industrial Engineering and Management China China Institute of Technology Taipei 245 China Department of GeneralStudies NationalTaichung Nursing College Taichung 403 China Basic Medical Science Education Center

AIM: Five representative waterborne pathogens were used to illustrate the relationship between chitosan’s antibac- terial activity and the surface characteristics of the bacterial cell wall. METHODS: chitosan was prepared with averaged 75 % or 95 % deacetylated degree to examine its antibacterial activity against waterborne pathogens. Fresh microbial inoculants for the antibacterial assessment were prepared on nutrient agar at 37oC for 24 h. The evaluation items of antibacterial mechanism included hydrophilicity and negative charge analysis of cell surface, and adsorptive characteristics of chitosan to bacterial cell. All the experiments were applied in triplicate tests at least. RESULTS: Although cell wall hydrophilicity was similar among Gram-negative bacteria, the distribution of negative charge on their cell surfaces was quite different. More negatively charged cell surfaces had a greater interaction with chitosan, a phenomenon further confirmed by transmission electron micrography (TEM). CONCLUSION: Results showed the hydrophilicity in Gram-negative bacteria was much higher than in Gram-positive ones. The correlation coefficient 0.988 between the amount of absorbed chitosan and its inhibition efficiency indicated a close relationship.

关键词： anti-bacterial agents chitosan cell wall

Effects of adsorption interferents on removal of Reactive Red 195 dye in wastewater by chitosan

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Journal of Environmental Sciences 2005年第5期17卷 766-769页

作者： WEN Yue-zhong LIU Wen-qi FANG Zhao-hua LIU Wei-ping Institute of Environmental Science Zhejiang University Hangzhou 310027 China Department of Environment Science and Engineering Nanchang University Nanchang 330029 China

Reactive Red 195, which is an azoic anionic dye characterized by the presence of five sulfonic groups and one azoic group, is efficiently removed using chitosan. The increasing chitosan dose had a dramatic positive impact on the achieved color removal, there was approximately a linear relationship between chitosan dose and color removal of dye before color removal reach maximum. Also, the increase of dye concentration led to the increase of chitosan dosage in order to get the same color remova l.92 mg/L of chitosan dosage was sufficient to achieve complete remove of dye at initial concentration of dye at 200 mg/L. For the higher concentrations of dye, high dosages were necessary to reach complete color removal. On the other hand, the use of adsorption interferents（Fe^2＋ , Na^＋ , HCO3^- and others） can be interesting, addition of ions had effect on the color removal of Reactive Red 195. Comparing with blank, addition of chemical species approximately decreased the color removal except Na^＋ and combination of Fe^2＋＋ HCO3^- . However, comparing with Fe^2＋ alone and HCO3^- alone, combination of Fe^2＋＋ HCO3^- increased the color removal.

关键词： chitosan Reactive Red 195 dye coagulation color removal

Aptasensor Based on Screen-Printed Carbon Electrodes Modified with CS/AuNPs for Sensitive Detection of Okadaic Acid in Shellfish

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Journal of Analysis and Testing 2023年第2期7卷 128-135页

作者： Ni Zeng Xinyi Wang Yiyang Dong Yan Yang Yingai Yin Lianhui Zhao Xu Wang College of Life Science and Technology Beijing University of Chemical TechnologyBeijing 100029China

Okadaic acid(OA),a small molecule substance derived from shellfish,is one of the most widely distributed marine toxins with acute symptoms of vomiting and diarrhea after accidental ingestion.For this,there is an urgently need for sensitive and reliable methods to detect OA in real shellfish samples.In this study,a simple aptasensor based on screen-printed carbon electrode(SPCE)with modification of chitosan(CS)and gold nanoparticles(Au NPs)was designed for electrochemical determination of OA,and the electrode surface was modified with Au NPs by potential-sweeping electrodeposition,which greatly improved the electrochemical response.The entire detection and characterization process were carried out by cyclic voltammetry(CV)with a linear correlation in the range of 0.01-100 ng/m L and a limit of detection(LOD)of 6.7 pg/m L.Furthermore,recovery rates of 92.3-116%were obtained demonstrating excellent accuracy through the recovery trial of mussel and scallop samples.

关键词： Okadaic acid Aptasensor Screen-printed carbon electrode chitosan Gold nanoparticles Cyclic voltammetry

Facile fabrication of a biocompatible composite gel with sustained release of aspirin for bone regeneration

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Bioactive Materials 2022年第5期7卷 130-139页

作者： Yunfan Zhang Xueyu Dou Lingyun Zhang Hufei Wang Ting Zhang Rushui Bai Qiannan Sun Xing Wang Tingting Yu Decheng Wu Bing Han Xuliang Deng Department of Orthodontics Peking University School and Hospital of StomatologyBeijingPR China National Center of Stomatology National Clinical Research Center for Oral DiseasesNational Engineering Laboratory for Digital and Material Technology of StomatologyBeijing Key Laboratory for Digital StomatologyResearch Center of Engineering and Technology for Computerized Dentistry Ministry of HealthNMPA Key Laboratory for Dental MaterialsBeijingPR China Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijingPR China University of Chinese Academy of Sciences BeijingPR China Department of Geriatric Dentistry Peking University School and Hospital of StomatologyBeijingPR China

Hydrogels are extracellular-matrix-like biomimetic materials that have wide biomedical applications in tissue engineering and drug delivery.However,most hydrogels cannot simultaneously fulfill the mechanical and cell compatibility requirements.In the present study,we prepared a semi-interpenetrating network composite gel(CG)by incorporating short chain chitosan(CS)into a covalent tetra-armed poly(ethylene glycol)network.In addition to satisfying physicochemical,mechanics,biocompatibility,and cell affinity requirements,this CG easily encapsulated acetylsalicylic acid(ASA)via electrostatic interactions and chain entanglement,achieving sustained release for over 14 days and thus promoting periodontal ligament stem cell(PDLSC)proliferation and osteogenic differentiation.In vivo studies corroborated the capacity of PDLSCs and ASA-laden CG to enhance new bone regeneration in situ using a mouse calvarial bone defect model.This might be attributed to PDLSCs and host mesenchymal stem cells expressing monocyte chemoattractant protein-1,which upregulated M2 macrophage recruitment and polarization in situ,indicating its appealing potential in bone tissue engineering.

关键词： Hydrogel Aspirin chitosan Drug sustained-release Bone tissue engineering

Water-ultrastable perovskite CsPbBr_(3)nanocrystals for fluorescence-enhanced cellular imaging

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Rare Metals 2023年第5期42卷 1624-1634页

作者： Cai-Li He Zi-Qi Meng Shu-Xia Ren Jian Li Ye Wang Hao Wu Hui Bu Yu Zhang Wei-Zhong Hao Shu-Lin Chen Rong-Rong Yan Huan Liu Yu-Fang Zhu Jin-Jin Zhao Department of Neurology The Second Hospital of Hebei Medical UniversityShijiazhuang050000China Institute of Materials for Energy Conversion School of Materials Science and EngineeringShijiazhuang Tiedao UniversityShijiazhuang050043China General Practice Department Liaocheng City People’s HospitalLiaocheng252000China Tianjin Key Laboratory of Retinal Functions and Diseases Tianjin Branch of National Clinical Research Center for Ocular DiseaseEye Institute and School of OptometryTianjin Medical University Eye HospitalTianjin300000China General Practice Department Hengshui People’s HospitalHengshui053000China The 984th Hospital of the PLA Integrated TCM&Western Medicine Department Beijing100094China KAUST Catalysis Center(KCC) Division of Physical Sciences and EngineeringKing Abdullah University of Science and Technology(KAUST)Thuwal23955-6900Saudi Arabia State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China Hebei Key Laboratory of Inorganic Nano-materials College of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang050024China

Metal halide perovskites have attracted much attention in biomedicine because of their excellent fluorescence energy conversion properties;however,poor water-stability and cytotoxicity limit its applications as a biomedical tracer,especially in cellular imaging.Herein,water-ultrastable perovskites C sPbBr_(3):Cs_(4)PbBr_(6)nanocrystals(NCs)encapsulated in chitosan are fabricated successfully using a water-triggered method.The as-synthesized CsPbBr_(3):Cs_(4)PbBr_(6)@CS(chitosan,CS)nanoparticles in water display enhanced fluorescence emission for 35 days.Further,the viability of glioma cells(U87 cells)incubated with different concentrations of CsPbBr_(3):Cs_(4)PbBr_(6)@CS nanoparticles(0-20μg·ml^(-1))for24 h is found to be higher than 90%.In artificial body fluid,analyses using laser confocal microscopy,the standard Cell Counting Kit-8(CCK-8)method,and flow cytometry demonstrated the good water ultrastability and high biocompatibility performance of CsPbBr_(3):Cs_(4)PbBr_(6)@CS nanoparticles in cellular imaging.Overall,the water-ultrastable halide perovskites support promising perspectives in biological cell tracing and intelligent medical technology.

关键词： Perovskites nanocrystals chitosan Waterultrastable High biocompatibility Cellular imaging

chitosan and Carboxymethylchitosan as High Turbidity Water Biocoagulants

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Journal of Renewable Materials 2020年第11期8卷 1489-1504页

作者： Raimundo N.Lima Júnior João L.I.O.Almeida Jones de Andrade Flávia O.M.S.Abreu Natural Sciences Program State University of Ceará-UECEFortalezaCE 60714-903Brazil Physical-Chemistry Department Institute of ChemistryFederal University of Rio Grande do Sul-UFRGSPorto AlegreRS 91501-970Brazil

Biocoagulants emerges as a promising technology in water treatment,in order to exploit renewable and biodegradable materials.The present work aims to study the coagulant action of chitosan and carboxymethylchitosan on water with very high turbidity(above 300 NTU),contrasting the physicochemical results with those obtained for aluminum sulphate.Carboxymethylchitosan was produced by the Williamson’s ethers synthesis and characterized by potentiometric titration,FTIR and 1 H-NMR.The coagulant tests were performed using synthetic water in a Jar-test equipment,through the induction of high and low velocity gradients,followed by sedimentation.The results showed turbidity and color removal efficiencies above 99%for the biocoagulants,by applying dosages much lower than those used for aluminum sulphate;the volume of sedimentable solids obtained at the end of the water treatment process was much lower when chitosan and carboxymethylchitosan were used as coagulants(reduction of 25%when compared to aluminum sulphate).In summary,carboxymethylchitosan is a non-toxic,renewable,biodegradable material with high efficiency as a coagulant for waters with very high turbidity,showing promise for in natura applications.

关键词： chitosan carboxymethylchitosan biocoagulants colloids and interfaces

Changes of cell membrane fluidity for mesenchymal stem cell spheroids on biomaterial surfaces

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World Journal of Stem Cells 2022年第8期14卷 616-632页

作者： Chui-Wei Wong Hao-Wei Han Shan-hui Hsu National Taiwan University Institute of Polymer Science and EngineeringTaipei 10617TaiwanChina National Health Research Institutes Institute of Cellular and System MedicineMiaoli 350TaiwanChina National Taiwan University Research and Development Center for Medical DevicesTaipei 10617TaiwanChina

BACKGROUND The therapeutic potential of mesenchymal stem cells(MSCs)in the form of threedimensional spheroids has been extensively demonstrated.The underlying mechanisms for the altered cellular behavior of spheroids have also been investigated.Cell membrane fluidity is a critically important physical property for the regulation of cell behavior,but it has not been studied for the spheroid-forming cells to date.AIM To explore the association between cell membrane fluidity and the morphological changes of MSC spheroids on the surface of biomaterials to elucidate the role of membrane fluidity during the spheroid-forming process of MSCs.METHODS We generated three-dimensional(3D)MSC spheroids on the surface of various culture substrates including chitosan(CS),CS-hyaluronan(CS-HA),and polyvinyl alcohol(PVA)substrates.The cell membrane fluidity and cell morphological change were examined by a time-lapse recording system as well as a highresolution 3D cellular image explorer.MSCs and normal/cancer cells were prestained with fluorescent dyes and co-cultured on the biomaterials to investigate the exchange of cell membrane during the formation of heterogeneous cellular spheroids.RESULTS We discovered that vesicle-like bubbles randomly appeared on the outer layer of MSC spheroids cultured on different biomaterial surfaces.The average diameter of the vesicle-like bubbles of MSC spheroids on CS-HA at 37℃ was approximately 10μm,smaller than that on PVA substrates(approximately 27μm).Based on time-lapse images,these unique bubbles originated from the dynamic movement of the cell membrane during spheroid formation,which indicated an increment of membrane fluidity for MSCs cultured on these substrates.Moreover,the membrane interaction in two different types of cells with similar membrane fluidity may further induce a higher level of membrane translocation during the formation of heterogeneous spheroids.CONCLUSION Changes in cell membrane fluidity may be a novel path to elucidate the complicated physiological alterations in 3D sph

关键词： Cell membrane fluidity Cell-cell interaction Cellular spheroids chitosan Hyaluronan