共查询到19条相似文献,搜索用时 159 毫秒
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采用层层自组装技术与光化学修饰方法相结合在聚氨酯材料表面固定生物多糖衍生物,首先合成具有光反应活性的叠氮壳聚糖,再在聚氨酯基材表面进行叠氮壳聚糖与香菇多糖硫酸酯的层层自组装,然后通过光化学反应对自组装多层膜修饰层进行交联,制备得到生物多糖衍生物层层自组装与光化学表面修饰的聚氨酯材料.通过红外光谱、X射线光电子能谱、水接触角测量仪、抗菌活性测试、溶血试验和血小板黏附测试等方法对被修饰聚氨酯材料的表面性能和生物性能进行了分析,测试结果表明修饰后的聚氨酯材料表面的亲水性和血液相容性得到改善,并且被修饰材料对大肠杆菌具有良好的抑制效果. 相似文献
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综述了国内外应用生物多糖进行医用高分子材料表面修饰的研究状况,其中重点介绍了葡聚糖、肝素及类肝素类物质、壳聚糖等多糖在高分子材料表面修饰的研究近况.多糖是自然界中含量最为丰富的生物大分子,几乎存在于所有的生命体中,具有很好的生物相容性,而且某些生物多糖还具有特殊的生物活性,因此用生物多糖进行医用高分子材料的表面修饰受到了国内外研究学者的关注.大量研究表明,经过生物多糖表面修饰的高分子材料可获得良好的生物相容性和某些优良的医学应用性能. 相似文献
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基于多巴胺自聚合及肝素固定改善钛的血液相容性 总被引:1,自引:0,他引:1
利用多巴胺自聚合及肝素固定的方法对纯钛进行表面修饰, 以改善其血液相容性. 采用水接触角测量、 X射线光电子能谱(XPS)和甲苯胺蓝法(TBO)等方法对所修饰的材料进行了表征. 采用溶血实验检测了材料的溶血性能, 并结合活化部分凝血活酶时间(APTT)测试和血小板黏附实验对所修饰材料的血液相容性进行了评价. 结果表明, 多巴胺能够在钛表面实现自聚合, 肝素可以共价接枝在聚多巴胺层上, 经肝素修饰后的材料的表面亲水性显著提高, 而且具有较低的溶血率, APTT时间显著延长, 血小板的黏附数量和被激活程度也显著降低. 因此, 纯钛经多巴胺自聚合以及肝素接枝修饰后的血液相容性得到了显著改善, 有望成为具有抗凝血功能的新型心血管植入材料. 相似文献
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通过层层静电自组装法将溶菌酶和聚苯乙烯磺酸钠(PSS)交替沉积在羊毛纤维表面, 赋予其抗菌性. 应用扫描电镜(SEM)考察组装后纤维表面形态, Zeta电位、染色、溶菌酶活性测试研究纤维表面组装机制并考察改性羊毛抗菌效果. SEM结果表明组装后纤维表面粗糙, 部分凹槽被填埋, 证明溶菌酶/PSS自发组装到纤维表面. 表面电位、染料上染量、溶菌酶活力随纤维表面沉积物质不同, 均呈现明显的“层层交替振荡”现象, 证实了组装后纤维表面电荷的交替变化|织物紫外线透过率随组装层数增加呈近似线性降低, 表明溶菌酶在羊毛表面实现了多层组装, 揭示了羊毛纤维表面抗菌功能涂层的层层静电自组装构筑机制. 同时, 组装层数增多, 溶菌酶活性逐渐增大. 载酶羊毛抗菌率达到91.7%, 具有良好的抗菌性能. 相似文献
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Elena Stoleru Cornelia Vasile Anamaria Irimia Mihai Brebu 《Molecules (Basel, Switzerland)》2021,26(15)
Here we introduce a new method aiming the immobilization of bioactive principles onto polymeric substrates, combining a surface activation and emulsion entrapment approach. Natural products with antimicrobial/antioxidant properties (essential oil from Syzygium aromaticum—clove and vegetal oil from Argania spinosa L—argan) were stabilized in emulsions with chitosan, a natural biodegradable polymer that has antimicrobial activity. The emulsions were laid on poly(lactic acid) (PLA), a synthetic biodegradable plastic from renewable resources, which was previously activated by plasma treatment. Bioactive materials were obtained, with low permeability for oxygen, high radical scavenging activity and strong inhibition of growth for Listeria monocytogenes, Salmonella Typhimurium and Escherichia coli bacteria. Clove oil was better dispersed in a more stable emulsion (no separation after six months) compared with argan oil. This leads to a compact and finely structured coating, with better overall properties. While both clove and argan oils are highly hydrophobic, the coatings showed increased hydrophilicity, especially for argan, due to preferential interactions with different functional groups in chitosan. The PLA films coated with oil-loaded chitosan showed promising results in retarding the food spoilage of meat, and especially cheese. Argan, and in particular, clove oil offered good UV protection, suitable for sterilization purposes. Therefore, using the emulsion stabilization of bioactive principles and immobilization onto plasma activated polymeric surfaces we obtained a bioactive material that combines the physical properties and the biodegradability of PLA with the antibacterial activity of chitosan and the antioxidant function of vegetal oils. This prevents microbial growth and food oxidation and could open new perspectives in the field of food packaging materials. 相似文献
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Dong B Jiang H Manolache S Wong AC Denes FS 《Langmuir : the ACS journal of surfaces and colloids》2007,23(13):7306-7313
A simple cold plasma technique was developed to functionalize the surfaces of polyamide (PA) and polyester (PET) for the grafting of polyethylene glycol (PEG) with the aim of reducing biofilm formation. The surfaces of PA and PET were treated with silicon tetrachloride (SiCl4) plasma, and PEG was grafted onto plasma-functionalized substrates (PA-PEG, PET-PEG). Different molecular weights of PEG and grafting times were tested to obtain optimal surface coverage by PEG as monitored by electron spectroscopy for chemical analysis (ESCA). The presence of a predominant C-O peak on the PEG-modified substrates indicated that the grafting was successful. Data from hydroxyl group derivatization and water contact angle measurement also indicated the presence of PEG after grafting. The PEG-grafted PA and PET under optimal conditions had similar chemical composition and hydrophilicity; however, different morphology changes were observed after grafting. Both PA-PEG and PET-PEG surfaces developed under optimal plasma conditions showed about 96% reduction in biofilm formation by Listeria monocytogenes compared with that of the corresponding unmodified substrates. This plasma functionalization method provided an efficient way to graft PEG onto PA and PET surfaces. Because of the high reactivity of Si-Cl species, this method could potentially be applied to other polymeric materials. 相似文献
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壳多糖抑制细菌生长的构效关系 总被引:6,自引:0,他引:6
运用化学结构已清楚, 分属4大系列的29种壳多糖, 以4种不同类型的细菌(革兰氏阳性菌Ecoli K1、革兰氏阴性菌Bacillus cereus、Bacillus megaterium和Staphlylococcu aureus)为研究对象, 进行了壳多糖抑菌能力构效关系的研究. 在实验中采用96孔平板, 用计算机\|吸光值读数仪直接测定每个孔的吸光值, 获得了各个细菌在不同壳多糖浓度中的生长曲线和壳多糖抑制细菌生长的最低抑制浓度(MIC, Minimum inhibit concentration). 通过比较同一(各个)系列的壳多糖在这些相同(不同)细菌的MIC变化规律与壳多糖的化学结构的关系, 发现同一壳多糖对不同的细菌的MIC值是不相同的, 因而壳多糖抑制细菌生长的能力首先与细菌本身特点有关, 但与是否为革兰氏阳性菌或阴性菌无直接的相关性; 同一细菌对不同化学结构的壳多糖有一定的相关性, 在壳多糖的聚合程度(DP)相同的条件下, 壳多糖中氨基被乙酰化(DA)的程度越低, 壳多糖抑制细菌生长的MIC值越低, 壳多糖抑制细菌生长的能力就越强; 同样,在DA相同的情况下, 分子越小, 壳多糖抑制细菌生长的MIC值越低, 抑制细菌生长的能力越强. 根据上述实验结果, 初步推测壳多糖抑制细菌生长的机制可能与其在溶液中所带的正电荷多少有关. 相似文献
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The antibacterial activity of water-soluble chitosan derivatives prepared by Maillard reactions against Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Escherichia coli, Shigella dysenteriae, and Salmonella typhimurium was examined. Relatively high antibacterial activity against various microorganisms was noted for the chitosan-glucosamine derivative as compared to the acid-soluble chitosan. In addition, it was found that the susceptibility of the test organisms to the water-soluble chitosan derivative was higher in deionized water than in saline solution. Metal ions were also found to reduce the antibacterial activity of the water-soluble chitosan derivative on S. aureus. The marked increase in glucose level, protein content and lactate dehydrogenase (LDH) activity was observed in the cell supernatant of S. aureus exposed to the water-soluble chitosan derivative in deionized water. The results suggest that the water-soluble chitosan produced by Maillard reaction may be a promising commercial substitute for acid-soluble chitosan. 相似文献
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Simona Lupínkov Markta Kaimlov Martin Kormunda Zdeka Kolsk 《Surface and interface analysis : SIA》2021,53(1):108-117
Antimicrobial materials with immobilized particles are of considerable interest. Sulfur, as one of the abundant elements on earth, is cheap and environmentally friendly; therefore, sulfur particles (SPs) can be used as an effective, nontoxic and low‐cost alternative to metal particles. SPs were prepared by precipitation method using sodium thiosulfate and hydrochloric acid in the presence of chitosan as a stabilizer. Further, SPs were grafted on polyethylene terephthalate (PET) foil activated by ultraviolet radiation. The changes in surface properties of modified foils were characterized by contact angle measurement, electrokinetic analysis and X‐ray photoelectron spectroscopy (XPS). The contact angle decreased on the UV‐treated sample, owing to the formation of oxidized groups. The presence of nitrogen and sulfur on the polymer surface, revealed by XPS, showed that chitosan‐capped SPs were bound to this surface. The surface morphology of samples and particle sizes were examined by scanning electron microscopy. The size of SPs increased after grafting on surface to a few micrometres. The antibacterial activity of the PET samples was tested against Staphylococcus epidermidis and Escherichia coli bacteria strains. UV‐treated samples grafted with one of the tested chitosan‐capped SPs demonstrated antibacterial effect against both of the bacteria strains. This new nanocomposite has potential to be used in medical applications as an antibacterial agent or in food processing as an antimicrobial food packaging material. Food spoilage caused by microorganisms such as E. coli during distribution and storage has a major impact on food quality and shelf life. 相似文献
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使用浓HNO3和浓H2O2对活性炭进行常温氧化改性,用FTIR和N2吸附法对活性炭进行表面分析,用AAS、SEM、XRD研究银在活性炭表面的吸附和分布特征,并研究了载银活性炭的抗茵性能.结果表明,活性炭经浓HNO3常温改性后,比表面积提高,而经浓H2O2常温改性后,比表面积略有下降,但都使活性炭表面含氧基团增加.改性后,活性炭表面增加的含氧基团为[Ag(NH3)2] 的还原吸附提供更多的活性点,使银的吸附量增大5倍多,银颗粒更加密集,大小更加均一.研究表明,载银活性炭具有明显的抗茵作用,其中对金黄色葡萄球菌的杀灭效果优于对大肠杆菌的杀灭效果,氧化改性使载银活性炭抗茵作用显著增强,其中硝酸改性现象更加明显. 相似文献
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Win‐Chun Jao Chien‐Hong Lin Jui‐Yuan Hsieh Yi‐Hsing Yeh Chia‐Yi Liu Ming‐Chien Yang 《先进技术聚合物》2010,21(8):543-553
Aiming to improve the hydrophilicity, antibacterial activity, cytocompatibility, and hemocompatibility of poly(butyleneadipate‐co‐terephthalate) (PBAT) films, PBAT films were treated with ozone, grafted with chitosan (CS), and followed by covalent immobilization of either heparin (HEP) or hyaluronic acid (HA). The surface graft density of modified PBAT films was detected by X‐ray photoelectron spectroscopy (XPS) and dyeing. The surface roughness of PBAT films was measured using an atomic force microscope (AFM). After immobilizing CS, PBAT films acquired antibacterial activity against Staphylococcus aureus and Escherichia coli. The adsorption of human serum albumin (HSA) and human plasma fibrinogen (HPF) on PBAT–CS–HEP and PBAT–CS–HA films was lower compared to that of native PBAT. Moreover, HEP immobilization could effectively reduce platelet adhesion and prolong the blood coagulation time, thereby improving the blood compatibility of PBAT. In addition, the growth of L929 fibroblasts was improved for HEP or HA immobilized PBAT, suggesting this surface modification was non‐cytotoxic. Furthermore, PBAT–CS–HEP and PBAT–CS–HA exhibited higher cell proliferation than native PBAT. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Antibacterial mechanism of chitosan microspheres in a solid dispersing system against E. coli 总被引:6,自引:0,他引:6
Kong M Chen XG Liu CS Liu CG Meng XH Yu le J 《Colloids and surfaces. B, Biointerfaces》2008,65(2):197-202
In this study, we investigated the antibacterial mechanism through the interfacial contacting inhibition behaviors of chitosan antimicrobials against Escherichia coli in solid dispersing state. Chitosan microspheres (CMs) were prepared by emulsification cross-linking reaction, and oleoyl-CMs (OCMs) were obtained by introduction of oleoyl groups to the chitosan. The CMs were with smooth surface and spherical shape of diameter of about 124 microm. The antibacterial activity was directly proportional to the concentration and the hydrophobic property of CMs. The fluorescence experiments indicated CMs had influenced the structure of membrane, especially the OCMs were speculated to interact with proteins on the cell membrane. SEM photographs showed E. coli adhered to the surface of the CMs and provided evidences for the disruption of the cells, while the bacterium conglomerated on the surface of the OCMs. The CMs changed the permeability of membrane and caused cellular leakage that correlated with the hydrophobic interaction between CMs and cytoplasmic membrane phospholipids of Gram-negative bacteria. Solid dispersing system makes the antibacterial activities of CMs counted as a sequent event-driven to study the antibacterial mechanism of chitosan originally. 相似文献
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ABSTRACT: BACKGROUND: The aim of this study is to investigate the functions of polymers and size of nanoparticles on the antibacterial activity of silver bionanocomposites (Ag BNCs). In this research, silver nanoparticles (Ag NPs) were incorporated into biodegradable polymers that are chitosan, gelatin and both polymers via chemical reduction method in solvent in order to produce Ag BNCs. Silver nitrate and sodium borohydride were employed as a metal precursor and reducing agent respectively. On the other hand, chitosan and gelatin were added as a polymeric matrix and stabilizer. The antibacterial activity of different sizes of silver nanoparticles was investigated against Gram-positive and Gram-negative bacteria by the disk diffusion method using Mueller-Hinton Agar. RESULTS: The properties of Ag BNCs were studied as a function of the polymer weight ratio in relation to the use of chitosan and gelatin. The morphology of the Ag BNCs films and the distribution of the Ag NPs were also characterized. The diameters of the Ag NPs were measured and their size is less than 20 nm. The antibacterial trait of silver/chitosan/gelatin bionanocomposites was investigated. The silver ions released from the Ag BNCs and their antibacterial activities were scrutinized. The antibacterial activities of the Ag BNC films were examined against Gram-negative bacteria (E. coli and P. aeruginosa) and Gram-positive (S. aureus and M. luteus) by diffusion method using Muller-Hinton agar. CONCLUSIONS: The antibacterial activity of Ag NPs with size less than 20 nm was demonstrated and showed positive results against Gram-negative and Gram-positive bacteria. The Ag NPs stabilized well in the polymers matrix. 相似文献