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21.
Emilia Piosik Marta Ziegler-Borowska Dorota Cheminiak-Dudkiewicz Tomasz Martyski 《International journal of molecular sciences》2021,22(5)
An adsorption process of magnetite nanoparticles functionalized with aminated chitosan (Fe3O4-AChit) showing application potential in nanomedicine into cell membrane models was studied. The cell membrane models were formed using a Langmuir technique from three selected phospholipids with different polar head-groups as well as length and carbon saturation of alkyl chains. The research presented in this work reveals the existence of membrane model composition-dependent regulation of phospholipid-nanoparticle interactions. The influence of the positively charged Fe3O4-AChit nanoparticles on a Langmuir film stability, phase state, and textures is much greater in the case of these formed by negatively charged 1,2-dipalmitoyl-sn-glycero-3-phospho-rac-(1-glycerol) (DPPG) than those created by zwitterionic 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and 2-oleoyl-1-palmitoyl-sn-glycero-3-phosphocholine (POPC). The adsorption kinetics recorded during penetration experiments show that this effect is caused by the strongest adsorption of the investigated nanoparticles into the DPPG monolayer driven very likely by the electrostatic attraction. The differences in the adsorption strength of the Fe3O4-AChit nanoparticles into the Langmuir films formed by the phosphatidylcholines were also observed. The nanoparticles adsorbed more easily into more loosely packed POPC monolayer. 相似文献
22.
Laura Nicolle Jens Casper Melanie Willimann Cline M. A. Journot Pascal Detampel Toma Einfalt Hiu Man Grisch-Chan Beat Thny Sandrine Gerber-Lemaire Jrg Huwyler 《International journal of molecular sciences》2021,22(8)
There is an increasing interest in cationic polymers as important constituents of non-viral gene delivery vectors. In the present study, we developed a versatile synthetic route for the production of covalent polymeric conjugates consisting of water-soluble depolymerized chitosan (dCS; MW 6–9 kDa) and low molecular weight polyethylenimine (PEI; 2.5 kDa linear, 1.8 kDa branched). dCS-PEI derivatives were evaluated based on their physicochemical properties, including purity, covalent bonding, solubility in aqueous media, ability for DNA condensation, and colloidal stability of the resulting polyplexes. They were complexed with non-integrating DNA vectors coding for reporter genes by simple admixing and assessed in vitro using liver-derived HuH-7 cells for their transfection efficiency and cytotoxicity. Using a rational screening cascade, a lead compound was selected (dCS-Suc-LPEI-14) displaying the best balance of biocompatibility, cytotoxicity, and transfection efficiency. Scale-up and in vivo evaluation in wild-type mice allowed for a direct comparison with a commercially available non-viral delivery vector (in vivo-jetPEI). Hepatic expression of the reporter gene luciferase resulted in liver-specific bioluminescence, upon intrabiliary infusion of the chitosan-based polyplexes, which exceeded the signal of the in vivo jetPEI reference formulation by a factor of 10. We conclude that the novel chitosan-derivative dCS-Suc-LPEI-14 shows promise and potential as an efficient polymeric conjugate for non-viral in vivo gene therapy. 相似文献
23.
壳聚糖是制备纸张防油剂潜在的理想材料,但其价格高昂、吸湿性强,需通过改性赋予其"一剂多效"功能(如在防油的同时兼顾防水、抗菌或水蒸气阻隔等功能),以提高其工业应用价值.结合壳聚糖的防油机理,总结了壳聚糖基防油剂防油性能的影响因素,综述了近年来防水型、抗菌型和水蒸气阻隔型壳聚糖基防油剂的研究现状,并对壳聚糖基防油剂的未来发展方向进行了展望. 相似文献
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A chitosan (CTN)/silica‐supported nanosized palladium catalyst was obtained from a silica‐supported chitosan palladium complex through a complex transition method. An adsorption model was employed to simplify the structure of the di‐supporter. It was indicated that when the polymer coil adsorbed on the silica surface with even a monolayer the catalytic activity would reach an optimum value, and different situations of the, nanosized palladium particles would cause a different catalysis. The molar ratio of the chitosan structure unit to the palladium would affect the metal's size, which therefore influenced its catalytic activity. The experimental results corresponded with the inferences. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 989–994, 2002 相似文献
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2-羟丙基三甲基氯化铵壳聚糖的制备及其表征 总被引:18,自引:0,他引:18
以脱乙酰度为90%的壳聚糖(CTS)为原料,异丙醇为溶剂,w(NaOH)=40 0%的水溶液为催化剂,3 氯 2 羟丙基三甲基氯化铵(CTA)为改性剂,在m(NaOH)∶m(CTS)=1 0∶1 0,m(CTA)∶m(CTS)=4 0∶1 0,反应温度65 0℃下制备了2 羟丙基三甲基氯化铵壳聚糖(HTCC)。实验结果表明,在反应时间达到或超过9 0h时,得到的HTCC产品的接枝度超过90 0%,在pH=6 7~7 0的水中可完全溶解形成w(HTCC)=3 0%的溶液。IR和1HNMR的结果表明,接枝反应主要发生在CTS的氨基上。 相似文献
28.
将壳聚糖/钙盐复合膜浸泡在磷酸二氢钾溶液中制备了壳聚糖/磷钙杂化膜.用电子扫描电镜观察杂化膜和膜内磷钙微粒的形貌,研究了杂化膜的力学性能、溶胀率、吸光度及热稳定性.结果表明,杂化膜内磷钙晶体为柱状和层状结构,磷钙被包裹在杂化膜内,并与壳聚糖膜形成紧密的连续结构.随着膜中磷钙的质量分数从2.1%增加到8.0%,膜的溶胀率从102%增加到144%,其在200~800 nm波长范围的吸光度也逐渐增加.当磷钙的质量分数为7.0%时,杂化膜的力学性能最佳,其拉伸强度为54.42 MPa、弹性模量为4045.72 MPa、断裂伸长率为4.85%.杂化膜的热分解温度为299℃,高于壳聚糖膜的分解温度290℃.这种具有层状磷钙结构的杂化膜具有良好的生物相容性,可作为一种潜在的支架材料. 相似文献
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An investigation was undertaken on the application of dilute chitosan solutions gelled by tyrosinase‐catalyzed reaction with 3,4‐dihydroxyphenethylamine (dopamine). The tyrosinase‐catalyzed reaction with dopamine conferred water‐resistant adhesive properties to the semidilute chitosan solutions. The viscosity of the chitosan solutions increased highly by the tyrosinase‐catalyzed reaction and the subsequent reactions between o‐quinone compounds and chitosan. These highly viscous, gel‐like modified chitosan materials were allowed to spread onto the surfaces of the glass slides, which were tightly lapped together and held them in water. Tensile shear adhesive strength of over 400 kPa was observed for the modified chitosan samples. The increase in the amino group concentration of the chitosan solutions and the molecular mass of the chitosan used effectively led to the increase in adhesive strength of the glass slides. In addition, in the case where the chitosan solution was gelled by the enzymatic reaction with dopamine in the presence of poly(ethylene glycol), adhesive strength sharply increased at shorter reaction times concomitantly with the increase in the viscosity of the chitosan solutions because the tyrosinase activity effectively was retained by poly(ethylene glycol). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1818–1827, 2007 相似文献