O-己酰化壳聚糖季铵盐的合成及其抗菌活性研究

采用两步法合成N,N,N-三甲基壳聚糖季铵盐,再用己酰氯改性,得到N,N,N-三甲基-O-己酰化壳聚糖季铵盐(TMHC)。产物用1 H NMR、FT-IR和EA等进行表征。抗菌实验结果表明,酰化改性能有效提高壳聚糖季铵盐的抗菌活性,并且随着酰化度的提高抗菌活性增加;TMHC对革兰氏阳性菌S.au-reus的抗菌活性比革兰氏阴性菌E.coli强;另外,相同浓度(50mmol/L)金属离子对TMHC抗菌活性的抑制作用按以下顺序递减:Ba2+>Ca2+>Mg2+,而同一金属离子(Mg2+)对TMHC抗菌活性的抑制作用则随着离子浓度的增加而增加。     

季铵盐壳聚糖抗菌纸的性能研究

以季铵盐壳聚糖为抗菌剂处理普通成纸,制备了包装用抗菌纸。采用抑菌圈法评价了该抗菌纸对大肠杆菌和金黄色葡萄球菌的抑制效果,研究了季铵盐壳聚糖的浓度对抗菌纸厚度、抗张强度、耐破度和抑菌性能的影响。结果表明,抗菌纸的抗张强度及耐破度均较原纸有所增加,厚度没有明显变化,能满足包装需求,且具有良好的抗菌性能,其抗菌效果随季铵盐壳聚糖浓度的增加而增强,并且相同季铵盐壳聚糖浓度下的抗菌纸对金黄色葡萄球菌的抑菌效果要好于大肠杆菌。     

壳聚糖季铵盐抗菌剂的研究进展

壳聚糖是自然界中唯一存在的碱性多糖,具有生物可降解性、生物相容性、安全性和抗菌性等优良性能,由于壳聚糖所具有的抗菌性能,其在伤口缝合、处理植物种子、消毒剂、洗手液等方面获得了广泛的应用.季铵盐型壳聚糖衍生物材料是提高壳聚糖抗菌性的重要方向之一,也是抗菌材料研究的热点领域.本文综述了国内外有关壳聚糖季铵盐的不同制备方法,...     

壳聚糖季铵盐/有机累托石纳米复合材料的抗菌性能研究

合成了壳聚糖季铵盐, 并通过溶液插层法将其插层进入有机累托石层间制备纳米复合材料, 研究表明, 当壳聚糖季铵盐与有机累托石的质量比为2∶1时, 其获得了4.8nm的最大层间距. 抗菌结果显示, 在偏酸、中性及偏碱性条件下, 所有的纳米复合材料都具有较好的抗菌性能, 且与有机累托石的含量和层间距成正比. 与壳聚糖季铵盐及有机累托石相比, 纳米复合材料对革兰氏阳性菌、革兰氏阴性菌及真菌的抗菌性能大大提高, 对金黄色葡萄球菌和枯草芽孢杆菌的最小抑制浓度仅为0.00313% (W/V), 且能在30min内杀死90%以上的金黄色葡萄球菌, 80%以上的大肠杆菌. 最后, 通过TEM和SEM结果探讨了其抗菌机理.     

季铵盐壳聚糖及其纳米粒子作为基因载体的研究

评价N,N,N-三甲基壳聚糖盐酸盐(TMC)及其纳米粒子对质粒DNA(pDNA)的负载及保护能力,考察了其纳米复合物对人类肝癌细胞株(HepG 2细胞)的转染能力。通过复凝聚法制备TMC/pDNA纳米粒子,并采用透射电镜及原子力显微镜表征粒子形态和粒径;采用凝胶阻滞分析观察其对pDNA的保护情况;采用四噻氮唑盐(MTT)比色法测定细胞毒性;以Lipofectamine 2000转染试剂作为阳性对照,检测其对HepG 2细胞的转染活性;采用荧光倒置显微镜观察转染情况。结果表明负载pDNA的TMC纳米粒子多呈球形,粒径为100～300nm,能有效地包裹和保护基因不被DNaseⅠ酶消化;当TMC与pDNA的质量比为10∶1时,在48h达到最高的转染效率。     

季铵盐型硅油的合成与性能研究

带季铵盐基团的硅油具有良好的抗菌功能,可广泛应用于织物处理、医用材料等领域。以含氢硅油为基本原料,与烯丙基缩水甘油醚发生加成反应合成环氧基硅油,进一步与N,N-二甲基烷基胺发生加成反应合成带季铵盐基团的硅油。采用红外光谱、差示扫描量热等分析方法对产物进行表征,研究季铵盐型硅油对大肠杆菌、金黄色葡萄球菌、白色念珠菌、痢疾菌、粪肠菌的抗菌性能。结果表明,含氢硅油经过两步加成反应生成了季铵盐型硅油。N,N-二甲基胺碳链长度以及胺基与环氧基团物质的量比对季铵盐型硅油的分子结构和热性能有显著影响,随着N,N-二甲基胺碳链长度增大,季铵盐型硅油结晶温度变化不明显,熔融温度升高,热分解温度下降,随着胺基与环氧基团物质的量比增大,季铵盐型硅油结晶温度下降,热分解温度下降。季铵盐型硅油抗菌性随碳链长度的增大而降低,抗菌性以胺基与环氧基团物质的量比为0.8∶1最优。     

季铵盐改性SiO_2纳米颗粒的制备及其抗菌性能

选用季铵盐作为抗菌剂,对纳米SiO2颗粒进行表面改性。对合成的季铵盐进行了FT-IR表征。通过FTIR、接触角、Zeta电位等手段研究了烷基链长度及纳米颗粒尺寸对改性纳米SiO2性能的影响,考察了改性纳米SiO2颗粒的抗菌性能。结果表明季铵盐接枝纳米SiO2颗粒表面带正电,随着烷基链的增长,疏水性渐强。抗菌测试表明,改性后的纳米SiO2对金黄色葡萄球菌有很好的抗菌性,24h可以全部杀死浓度为1.72×106 CFU/mL的金黄色葡萄球菌。     

卤胺化合物/季铵盐抗菌整理棉织物研究

市场对抗菌纺织品需求越来越大。选用卤胺化合物和季铵盐两种抗菌剂处理棉织物。合成了5,5-二甲基-3-(3'-三乙氧基硅丙基)-海因(DTH)及其聚合物(PDTH),3-(三乙氧基甲硅烷基)丙基三甲基氯化铵(Quat-C1),3-(三乙氧基甲硅烷基)丙基二甲基十八烷基氯化铵(Quat-C18)。抗菌性能测试结果表明两种抗菌剂混合使用时抗菌效果比单独使用卤胺化合物有所下降,但比单独使用季铵盐有所提高;且季铵盐的加入可显著减少卤胺化合物的用量,从而节约成本;此抗菌整理对织物其他性能无明显影响。     

壳聚糖微球的季铵化及其抗菌性能的研究

采用乳化交联法制备了壳聚糖微球,并对其进行季铵化表面改性。实验分别考察了溶剂、反应时间和季铵化试剂C_4H_9Br与壳聚糖微球物质的量之比对季铵化壳聚糖微球的影响。研究结果表明,壳聚糖微球在乙腈溶液中分散较好,反应时间为12h,季铵化试剂与壳聚糖微球的物质的量之比为3∶1时,制备的季铵化壳聚糖微球效果较好。对壳聚糖、壳聚糖微球、季铵化壳聚糖微球进行抗菌性能测试,发现其抗菌性能的强度大小依次为:季铵化壳聚糖>壳聚糖微球>壳聚糖,其中季铵化壳聚糖微球的抑菌率为52.1%。     

壳聚糖衍生物的制备及其抑菌活性的研究

改进壳聚糖衍生物制备技术,并用红外光谱对其结构进行表征;并测定了所合成衍生物的稳定性、溶解性及pH值等相关性质,同时用改进后的CS衍生物进行抑菌实脸的初步研究.结果表明经过技术改进制备的3种不同分子量的CS衍生物具有良好水溶性且稳定性增强.两种CS衍生物在0.1%(w/v)处对大肠杆菌和金黄色葡萄球菌具有抑制作用,到0...     

接枝聚阳离子磁性微球的合成及抗菌活性

共沉淀法合成Fe3O4纳米颗粒,经硅烷偶联剂3-(异丁烯酰氧)丙基三甲氧基硅烷(MPS)表面双键功能化,与季铵盐化(苄基溴化或溴己烷化)甲基丙烯酸二甲基氨基乙酯(DMAEMA)单体自由基共聚,获得可循环利用的聚阳离子接枝的磁性抗菌微球(pQAC-Fe3O4)。颗粒形貌及表面性质通过X射线衍射(XRD)、红外(FT-IR)、动态光散射粒径分析(DLS)、透射电镜(TEM)、热重分析(TGA)等表征。测试pQAC-Fe3O4微球对革兰氏阳性、革兰氏阴性菌及真菌的抗菌活性,结果表明两种具有外磁场响应性的pQAC-Fe3O4颗粒均具有高效广谱杀菌性,且经磁分离回收循环利用10次后对大肠杆菌的杀菌率仍可达95%以上。颗粒杀菌效果不仅与接枝季铵盐基团的多少有关还与季铵盐取代基团有关。     

Preparation and antibacterial activity of chitosan microshperes in a solid dispersing system

In this study, we investigated the interface contacting inhibition behaviors of chitosan against bacterial in the dispersing state. For that purpose, chitosan microspheres (CMs) in the dispersing state was prepared by the emulsification cross-linking method. The CMs had smooth surface and spherical shape with the diameter of about 124 μm. They were stable after sterilization at 121°C and 150 kPa for 20 min. The CMs had similar antibacterial activity to that of chitosan in the solution form. Their antibacterial activities increased with the increase of the CM concentration, while decreased with the increase of pH of the system. It was found that the CMs with the degree of deacetylation (DD) of 63.6% exhibited the highest antibacterial activity, while the CMs with the DD of 83.7% exerted the lowest antibacterial activity among the three tested samples.     

Ag-羧甲基壳聚糖复合微粒的制备及其抑菌活性

壳聚糖经羧甲基化改性后得到水溶性较高的羧甲基壳聚糖（OCMC）,它具有优良的稳定性和抗菌性。对比OCMC在不同溶剂中的溶解度,发现OCMC在2wt%乙酸溶液中的溶解性最好。将OCMC与纳米Ag（AgNPs）复合得到Ag-OCMC复合微粒,采用UV-Vis、FTIR、XPS、TEM、SEM和TG-DTA对Ag-OCMC复合微粒的组成、微观结构和热性能进行表征。以大肠杆菌和金黄色葡萄球菌为模型菌种测试Ag-OCMC复合微粒对革兰氏菌的抗菌性能。结果表明:AgNPs为面心立方晶型,平均粒径为40~50 nm;AgNPs的引入提高了壳聚糖和OCMC的分解温度。Ag-OCMC复合微粒对革兰氏菌的抑菌活性明显高于单一壳聚糖基抗菌剂。      

Facile fabrication of superior antibacterial cotton fabric based on ZnO nanoparticles/quaternary ammonium salts hybrid composites and mechanism study

In the research for the safe and efficiently antibacterial cotton fabrics to minimize risk for human health, an organic–inorganic hybrid material of ZnO nanoparticles (NPs) and quaternary ammonium salt (QAS) was employed to modify cotton fabrics by a dipping–padding–drying method. The synergistic effects of ZnO NPs and QAS on the structure and antibacterial properties of cotton fabrics were studied in detail. Results displayed that the QAS and ZnO NPs were immobilized firmly in cotton fabric by the formation of chemical covalent bonds and silica gel structure. ZnO/QAS/cotton had a good inhibitory effect on the growth of E. coli and S. aureus, with superior antibacterial efficiency of >99.99%. ZnO/QAS/cotton preserved good mechanical property, water absorbability, and limpness. We also provided a detailed analysis of antibacterial mechanism for the hybrid materials. The contact mechanism and the Zn²⁺ release were considered as the main mechanisms for the ZnO/QAS/cotton, while the reactive oxygen species (ROS) generation only had a little contribution to the antibacterial activity. In short, the excellent integrated properties endowed the hybrid cotton fabrics as potential application in many fields, like healthcare, food packaging.     

含纳米银的明胶/壳聚糖纳米纤维的制备及其抗菌性能研究

以浓度为88%的甲酸溶液作为纺丝溶剂,采用静电纺丝和紫外光照射还原的方法制备了含纳米银颗粒的明胶/壳聚糖纳米纤维。研究发现,壳聚糖的加入量低于明胶质量的3/16时可以得到纳米纤维,纤维平均直径随着硝酸银加入量的增大而减小,纤维表面纳米银的平均直径随着硝酸银加入量的增大而增大,在纺丝体系中硝酸银的加入量存在一个极限值。所制得含纳米银的明胶/壳聚糖纳米纤维对金黄色葡萄球菌和绿脓杆菌具有较好的抑菌性能,纺丝时加入1%硝酸银制得纳米纤维膜的抑菌率达到99%以上,这种抗菌型纳米纤维可以应用于医用敷料等领域。     

N,N,N-三甲基-1-金刚烷基季铵盐的合成

以金刚烷胺为原料,通过艾希魏勒-克拉克反应(Eschweiler-Clarke)合成了N,N-二甲基金刚烷胺,优化反应条件为金刚烷胺∶甲酸∶甲醛的摩尔比为1∶5∶4,反应时间为18h,温度为98℃,产物收率93.4%,进而合成了N,N,N-三甲基-1-金刚烷基季铵盐,产物收率90.5%,其结构经1H-NMR,13C NMR,MS和GC-MS表征。     

Synthesis,characterization and antibacterial activity of superparamagnetic nanoparticles modified with glycol chitosan

Iron oxide nanoparticles (IONPs) were synthesized by coprecipitation of iron salts in alkali media followed by coating with glycol chitosan (GC-coated IONPs). Both bare and GC-coated IONPs were subsequently characterized and evaluated for their antibacterial activity. Comparison of Fourier transform infrared spectra and thermogravimetric data of bare and GC-coated IONPs confirmed the presence of GC coating on IONPs. Magnetization curves showed that both bare and GC-coated IONPs are superparamagnetic and have saturation magnetizations of 70.3 and 59.8 emu g⁻¹, respectively. The IONP size was measured as ∼8–9 nm by transmission electron microscopy, and their crystal structure was assigned to magnetite from x-ray diffraction patterns. Both bare and GC-coated IONPs inhibited the growths of Escherichia coli ATCC 8739 and Salmonella enteritidis SE 01 bacteria better than the antibiotics linezolid and cefaclor, as evaluated by the agar dilution assay. GC-coated IONPs showed higher potency against E. coli O157:H7 and Staphylococcus aureus ATCC 10832 than bare IONPs. Given their biocompatibility and antibacterial properties, GC-coated IONPs are a potential nanomaterial for in vivo applications.     

Synthesis,characterization and antibacterial activity of superparamagnetic nanoparticles modified with glycol chitosan

Abstract

Iron oxide nanoparticles (IONPs) were synthesized by coprecipitation of iron salts in alkali media followed by coating with glycol chitosan (GC-coated IONPs). Both bare and GC-coated IONPs were subsequently characterized and evaluated for their antibacterial activity. Comparison of Fourier transform infrared spectra and thermogravimetric data of bare and GC-coated IONPs confirmed the presence of GC coating on IONPs. Magnetization curves showed that both bare and GC-coated IONPs are superparamagnetic and have saturation magnetizations of 70.3 and 59.8 emu g^?1, respectively. The IONP size was measured as ～8–9 nm by transmission electron microscopy, and their crystal structure was assigned to magnetite from x-ray diffraction patterns. Both bare and GC-coated IONPs inhibited the growths of Escherichia coli ATCC 8739 and Salmonella enteritidis SE 01 bacteria better than the antibiotics linezolid and cefaclor, as evaluated by the agar dilution assay. GC-coated IONPs showed higher potency against E. coli O157:H7 and Staphylococcus aureus ATCC 10832 than bare IONPs. Given their biocompatibility and antibacterial properties, GC-coated IONPs are a potential nanomaterial for in vivo applications.