聚(4-乙烯基吡啶季铵盐-丙烯酰胺)的抗菌性能与机理研究

季铵盐型阳离子聚合物具有絮凝、缓蚀与杀菌等多种功能,据此,我们通过分子设计,先将丙烯酰胺与4-乙烯基吡啶（4-VP）进行共聚合,然后使用季铵化试剂硫酸二甲酯使共聚物阳离子化,制备了吡啶季铵盐型阳离子聚丙烯酰胺（QPAV）,本文报道QPAV的抗菌性能,并探讨其抗菌机理,结果表明,吡啶季铵盐型阳离子聚丙烯酰胺具有很强的抗菌性能,且其抗菌机理是基于杀菌而不仅仅是抑菌。     

甲壳低聚糖表面活性剂的制备及其表面活性研究

通过氧化降解壳聚糖制得水溶性甲壳低聚糖，再与二甲基十二烷基缩水甘油基氯化铵反应，得到了季铵盐型阳离子甲壳低聚糖表面活性剂。用红外光谱、核磁共振(^1H，^13C)、元素分析等分析手段对产物进行了结构表征，并研究了取代度对产物表面活性的影响规律。     

高效液相色谱-串联质谱法测定冷冻饮品中的5种季铵盐

建立了快速测定冷冻饮品中5种季铵盐(十二烷基二甲基苄基氯化铵、十四烷基二甲基苄基氯化铵、十六烷基二甲基苄基氯化铵、十六烷基二甲基苄基氯化铵、十二烷基三甲基氯化铵和双癸基二甲基氯化铵)的高效液相色谱-串联质谱(HPLC-MS/MS)检测方法。样品经乙腈-乙酸乙酯(1∶1,体积比)提取2次,提取液于-20℃冷冻脱脂净化,经CAPCELL PAK CR(1∶20)色谱柱分离,以乙腈-5 mmol/L乙酸铵(含0.1%甲酸)水溶液为流动相,梯度洗脱,采用多反应监测(MRM)模式,基质外标法进行定量分析。结果表明,5种季铵盐在0.5～50.0μg/L质量浓度范围内线性关系良好,相关系数(r)均大于0.995。5种季铵盐的检出限为0.3～1.5μg/kg,定量下限为1.0～5.0μg/kg。样品基质在5.0、10.0和50.0μg/kg 3个加标水平下的平均回收率为80.3%～114%,相对标准偏差(RSD)为2.5%～8.3%。实际样品检测结果表明,冷冻饮品中存在季铵盐的残留污染。该方法操作便捷,灵敏度高,精密度良好,适用于冷冻饮品中5种季铵盐的定量检测。     

季铵盐类阳离子单体的合成工艺研究进展

对季铵盐类阳离子单体的合成工艺及结构改性研究进展进行了综述。基于季铵盐类阳离子单体的基本结构与性质,从合成反应基本历程及代表性制备工艺方法出发,介绍了二烯丙基季铵盐类、丙烯酰胺烷基季铵盐类和丙烯酰胺烷基季铵盐类三类最为重要的季铵盐阳离子单体的合成、聚合及结构改性最新研究进展,指出了已有研究工作的特色与不足,并认为开发高质量丙烯酰胺烷基季铵盐类单体及聚合物产品以及高纯度质量稳定的阳离子单体制备新工艺是今后应努力的方向。     

季铵化N,O-(2-羧乙基)壳聚糖的制备及其抑菌性能

以缩水甘油基三甲基氯化铵(GTMA)、缩水甘油基三乙基氯化铵(GTEA)、缩水甘油基三丙基氯化铵(GTPA)、缩水甘油基三丁基氯化铵(GTBA)和缩水甘油基二甲基苄基氯化铵(GDMBA)等活性季铵盐为季铵化试剂,对N,O-2-羧乙基壳聚糖(N,O-2-CEC)进行了化学改性,得到了系列季铵化N,O-2-CEC(QCEC...     

季铵盐阴离子交换膜研究进展

近年来,阴离子交换膜燃料电池的发展受到了广泛关注。开发具有碱稳定性能优异,电导率高的阴离子交换膜(AEMs)材料成为了研究的热点。AEMs主要由聚合物骨架和阳离子基团组成,这两者是影响膜碱稳定性和电导率的重要因素。本文综述了季铵盐类阴离子交换膜聚合物骨架结构中含有醚氧键和不含醚氧键的烷基季铵盐AEMs、N-螺环季铵盐AEMs和环季铵盐AEMs的碱稳定性、电导率等性能;总结了不同骨架结构季铵盐AEMs碱稳定性的差异;分析了季铵盐的降解机理。同时对于含有季铵盐阳离子交换基团的AEMs的结构设计进行了分析和展望。     

UPLC-MS/MS法测定冰淇淋与雪糕中3种季铵盐类化合物

基于固相萃取(SPE)技术和超高效液相色谱-质谱/质谱仪(UPLC-MS/MS),建立了一种测定冰淇淋和雪糕中3种季铵盐消毒剂(十二烷基二甲基苄基氯化铵、十六烷基二甲基苄基氯化铵和苄索氯铵)残留量的方法。样品融化混匀后,用乙腈提取和沉淀蛋白,提取液经弱阳离子交换(WCX)固相萃取柱净化,氮吹浓缩后,采用亲水色谱柱(HILIC)在0.1%甲酸乙腈-10 mmol/L乙酸铵流动相体系中等度分离,在质谱的电喷雾(ESI)离子源正模式和多反应监测(MRM)模式下测定。结果表明,3种季铵盐在0.5~20μg/L范围内线性关系良好,相关系数均大于0.999,方法的定量下限(S/N=10)为3.0~5.5μg/kg,3个加标水平的平均回收率为90.7%~102.2%,相对标准偏差(RSD,n=6)为2.4%~6.4%。该方法简单,准确灵敏,重现性好,适用于冰淇淋和雪糕中3种季铵盐消毒剂的检测。     

有机改性膨润土对己唑醇水悬浮体系物理稳定性的影响

利用4种季铵盐阳离子表面活性剂（十二烷基二甲基苄基氯化铵(1227)、十四烷基二甲基苄基氯化铵(1427)、十六烷基三甲基氯化铵(1631)和十八烷基三甲基氯化铵(1831)）分别对钠基膨润土（Na-Ben）进行有机改性,制得4种有机膨润土（1227-Ben、1427-Ben、1631-Ben和1831-Ben）并进行了红外光谱及X射线分析,考察了4种有机膨润土在水中的悬浮性能及对5%己唑醇水悬体系物理稳定性能的影响。 FT-IR及XRD分析结果表明,供试季铵盐阳离子的有机碳链均进入到膨润土的片层间。 水中悬浮性能测定实验表明,1831-Ben在水中悬浮性能相对较好,而其它3种均不理想,特别是1227-Ben和1427-Ben表现出强烈的斥水现象。 沉降试验表明,有机膨润土的使用有助于5%己唑醇水悬浮剂物理稳定性的提高,其中用1831-Ben制备出的水悬浮体系的物理稳定性明显优于其它3种,制剂析水率最低,屈服值与粘度最大,体系悬浮率最高,可见1831-Ben可以用作5%己唑醇水悬浮剂的抗沉降剂。     

季铵盐单体在蒙脱土中的插层原位聚合反应

通过四种结构相似的可聚合季铵盐(二甲基二烯丙基氯化铵、三甲基烯丙基氯化铵、丙烯酰氧乙基三甲基氯化铵、甲基丙烯酰氧乙基三甲基氯化铵), 通过蒙脱土层间构型排布的模拟及分析比较, 从分子水平上探讨了原位插层聚合反应中, 单体分子排列角度及构型对聚合反应的影响.     

反相高效液相色谱法测定复方化学消毒剂中苯扎氯铵

苯扎氯铵又名洁尔灭(BAC),是具有杀菌作用的季铵盐类阳离子表面活性剂,主要由3种正烷烃图1 BAC分子结构式F ig·1 Structure of BAC基(n-C12H25、n-C14H29和n-C16H33)取代的二甲基苄基氯化铵的同系物组成,结构式如图1。3种同系物的杀菌特性不同:n-C12H25-C9H13NC l是最有效的酵     

Adhesion of filamentous microbial cells on paper covered with ionic polymers by radiation polymerization

The adhesion of filamentous microbial cells such as Trichoderma reesei was studied by using carriers covered with polymers which were prepared by the radiation polymerization of ionic monomers. The weight of the cells adhering to the carriers increased with increasing cationic monomer content, indicating that the surface of the polymers prepared from cationic and hydrophobic monomers is suitable for the adhesion of the cells. The production of cellulase in the cells adhered to polymers from cationic monomers was higher than that in cells adhered to polymers prepared from anionic monomers. The growth of the cells adhered to the surfaces of the polymers was affected by the hydrophilicity of the polymers.     

Preparation and polymerization of methylenecyclobutene and 1-methyl-3-methylenecyclobutene

Methylenecyclobutene (MCB) and 1-methyl-3-methylenecyclobutene (MMCB) were synthesized, characterized, and polymerized by anionic and cationic initiators. Structural analyses of the polymers were carried out by infrared and NMR spectros-copy. The cationic polymerization of MCB appeared to proceed entirely by a 1,5-propagation mechanism to form low molecular weight polymers in low yields. Anionic polymerization of this monomer, on the other hand, proceeded primarily through a 1,2-propagation path, again forming only low molecular weight polymeric products in low yield. In contrast to MCB, the methyl-substituted monomer, MMCB, polymerized readily with cationic initiators to produce unusually high molecular weight polymers in high conversions. On the basis of both infrared and NMR spectroscopic analyses, it was concluded that the polymers also contained essentially only 1,5-addition repeating units. Anionic initiators such as n-BuLi were unable to induce polymerization of this monomer, but polymerization by Ziegler-Natta catalysts proceeded readily to yield polymers virtually identical in structure and molecular weight to those obtained with cationic initiators.     

纳米微晶纤维素聚合物的研究现状及应用前景

纳米微晶纤维素(NCC)具有广泛的兼容性和独特的物理尺寸效应,通过硫酸化、氧化、阳离子化、接枝和甲硅烷基化等化学改性可获得NCC聚合物,并赋予其独特的光学性质、流变性能和机械性能。NCC及其复合材料可应用于生物医药、航天航空、军事、建筑、造纸等领域。文章综述了NCC聚合物的研究进展及应用前景。     

含氟高分子基因载体

阳离子高分子被广泛应用为非病毒类基因载体,但这类高分子材料的转染效率与细胞毒性之间通常存在"恶性"关联,即获得高转染效率时往往会伴随严重的细胞毒性.如何制备兼具高效、低毒特点的高分子载体是成功实施基因治疗的关键.含氟高分子是一类具有独特理化性质的高分子,能够在低电荷密度条件下与核酸形成稳定的复合物,从而实现高效、低毒的基因转染.含氟功能基团可帮助阳离子高分子改善复合物稳定性、细胞内吞、内涵体逃逸、胞内核酸释放等多个环节,从而赋予了含氟高分子在基因递送过程中的氟效应.该专论系统地总结了含氟高分子基因载体的研究,介绍了含氟高分子的基因递送性能、作用机理以及在基因治疗、基因编辑中的应用,并对含氟高分子载体的未来发展进行了展望.     

基于门舒特金反应的酶触发自降解高分子载体及其在基因输送中的应用

用邻位苄基溴与双胺进行门舒特金反应,合成了2种线性的季铵盐阳离子聚合物.其中,含有酚基酯键的阳离子聚合物,一旦进入细胞后,可以在细胞内的酯酶催化下快速水解,使得聚合物自降解断裂为不带电的非季铵盐小分子,从而快速释放DNA,最终达到提高转染效率的目的.通过对复合物纳米颗粒的粒径和电势测定,证明了这2种阳离子聚合物都能够有效地结合DNA形成表面带正电的复合物纳米颗粒.凝胶阻滞电泳实验表明,所合成的阳离子聚合物都能稳定地包裹DNA.而在酯酶条件下,含有酚基酯键的阳离子聚合物可以发生降解,使得纳米复合物释放出DNA.同时,含有酚基酯键的阳离子聚合物由于其独特的可降解性,相比于PEI,降低了细胞毒性.在体外细胞转染实验中,2种阳离子聚合物都有较好的转染效果.其中酯酶响应的载体在高N/P下依然表现出较高的转染效率,说明该阳离子载体能够在细胞内有效降解并释放出DNA.     

Tuned Cationic Dendronized Polymer: Molecular Scavenger for Rheumatoid Arthritis Treatment

Cell‐free deoxyribonucleic acid (cfDNA) released from either dead or damaged cells serves as a key autoantigen in rheumatoid arthritis (RA). They can be recognized by nucleic acid (NA) sensors such as the toll‐like receptor (TLR), leading to activation of the innate immune system and chronic inflammation. Developed here is a cationic molecular scavenger, by screening cationic dendronized polymers, which eliminates cfDNA and inhibits TLR recognition and nucleic‐acid‐induced inflammation. The structure–property study demonstrates that toxicity, NA binding capacity, and biodistribution could be balanced to achieve maximum therapeutic effect by exquisite control of the molecular structure. In addition, the optimized cationic polymer effectively inhibited joint swelling, synovial hyperplasia, and bone destruction in collagen‐induced arthritis (CIA) rat models. The results offer support for synthetic polymers offering new paradigm in autoimmune disease treatment.     

High DNA‐Binding Affinity and Gene‐Transfection Efficacy of Bioreducible Cationic Nanomicelles with a Fluorinated Core

During the last two decades, cationic polymers have become one of the most promising synthetic vectors for gene transfection. However, the weak interactions formed between DNA and cationic polymers result in low transfection efficacy. Furthermore, the polyplexes formed between cationic polymers and DNA generally exhibit poor stability and toxicity because of the large excess of cationic polymer typically required for complete DNA condensation. Herein, we report the preparation of a novel class of bioreducible cationic nanomicelles by the use of disulfide bonds to connect the cationic shell to the fluorocarbon core. These bioreducible nanomicelles form strong interactions with DNA and completely condense DNA at an N/P ratio of 1. The resulting nanomicelle/DNA polyplexes exhibited high biocompatibility and performed very effectively as a gene‐delivery system.     

A comparative study of interaction of ibuprofen with biocompatible polymers

In this paper we are reporting the interaction of a non-steroidal anti-inflammatory drug ibuprofen (IBF) with various biocompatible polymers. Being amphiphilic, the drug interacts with the polymers similar to the interaction of surfactants and polymers. Therefore, we have considered the polymer-amphiphile interaction approach using conductimetry. The polymers of different charges (cationic, anionic, and nonionic) have been taken for the study. It was found that the critical aggregation concentration (cac) decreases on increasing the polymer concentrations of cationic as well as nonionic polymers whereas it increases for anionic polymers. The results imply that anionic IBF interacts with cationic and nonionic polymers more strongly as compared to the anionic polymers. A possible anionic-anionic repulsion is responsible for the weak interaction of IBF with anionic polymers. On the other side, the critical micelle concentration (cmc) increases for all polymers which is a usual indication of the interaction between amphiphiles and polymers. Free energies of aggregation (ΔG_agg) and micellization (ΔG_mic) were also computed with the help of degrees of micelle ionization obtained from the specific conductivity - [IBF] isotherms.     

Organo-modified cationic silica nanoparticles/anionic polymer as flocculants

The synthesis of quaternized silica nanoparticles and its application to fine clay flocculation were investigated. N-trimethoxysilylpropyl-N,N,N-trimethylammonium chloride was used as a cationic reagent to introduce quaternary amine groups onto the surfaces of silica nanoparticles via the formation of covalent bonds between the methoxy groups of the cationic reagents and the silanol groups in the silica surface. The zeta potential, zeta, and charge density of the silica particles modified under various reaction conditions were determined. Dynamic clay flocculation experiments using a photometric dispersion analyzer (PDA) showed that the cationic silica alone contributed little to the flocculation. However, the cationic silica, in conjunction with an anionic polymer of high M(w) and low charge density, led to a significant improvement in the flocculation of fine clay particles. The mechanism of flocculation was explored by a systematic investigation of interaction between cationic silica and anionic polymers as well as of their adsorption behavior on clay surfaces. The influence of factors such as pH and electrolyte concentration on clay flocculation was also investigated.     

Amphiphilic branched polymers as antimicrobial agents

Cationic amphiphilic polymers were prepared from PEI and functional ethylene carbonates bearing cationic, hydrophobic or amphiphilic groups. The polymers are designed to exhibit antimicrobial properties. In a one-step addition, different functional ethylene carbonates were added to react with the primary amine groups of PEI. The water soluble polymers were studied regarding their ability to form soluble aggregates. Their hydrodynamic radii, their inhibition potential against proliferation of E. coli and their hemolytic potential were determined. A structure-property relationship was established by analyzing the antimicrobial activity as a function of the ratio of alkyl to cationic groups, length of the alkyl chains, and molecular weight of the PEI.