新型高分子季鏻盐改性抗菌塑料的制备及性能研究

高分子季鏻盐抗菌剂具有安全、高效的特点,使用过程中不会通过皮肤组织进行渗透。本文将实验室自制的新型高分子季鏻盐抗菌剂粉末与低密度聚乙烯(LDPE)基体材料共混,通过熔融挤出法制备了含梯度浓度抗菌剂的抗菌塑料,研究了不同抗菌剂添加浓度对基体材料熔融性质及其抗菌性能的影响,并探讨了抗菌塑料的生物安全性。结果表明,梯度浓度的抗菌剂改性塑料对金黄色葡萄球菌和大肠杆菌均有良好的抗菌效果;生物安全性测试结果表明,抗菌塑料的细胞毒性为0级,说明抗菌塑料具有较高的生物安全性。     

抗菌涂料的研究进展

抗菌涂料是涂料发展研究的重要方向之一。抗菌涂料是指在涂料中加入抗菌剂,使涂料具有抗菌性能,当用于室内涂装时可以有效降低居室、家具以及电器等表面的细菌密度。常用的抗菌剂包括有机抗菌剂、无机抗菌剂和天然抗菌剂3种。该文对抗菌涂料常用的3种类型抗菌剂进行介绍,并对其抗菌机理进行概述。     

抗菌聚合物的研究进展

微生物感染已经成为人类健康的第一杀手,同时给人们带来了巨大的经济损失,特别是在公共医疗卫生、食品安全等方面。使用抗菌剂是防治微生物滋生和繁殖的有效手段。与无机抗菌剂、有机抗菌剂和天然抗菌剂相比,抗菌聚合物因其有效官能团密度高、低毒、长效等优点,正成为目前科研的热点。本文介绍了抗菌聚合物的制备方法、分类和抗菌机理,并基于近五年来的文献资料,综述了在医疗领域、食品领域和纺织领域中抗菌聚合物的研究进展。     

溴化苄基取代吡啶类季铵盐的制备和抗菌性能

抗菌材料和抗菌制品的研究与应用一直是世界各国研究的重要课题~([1-3]),其中有机抗菌剂占据主要地位.季铵盐是研究比较多的一类有机抗菌剂,它们表现出良好的物理性质,如胶束浓度低,黏弹性好和溶解性强~([4]),同时此类抗菌剂具有强效的抗菌作用~([5]),引起了人们的极大兴趣.季铵盐广泛应用于医药、卫生、食品、饲料工业、农业、纺织、塑料、橡胶、造纸、水处理、油田开采、涂料、日常生活等多种领域~([6-10]).     

纳米抗菌剂的研究进展

纳米抗菌剂是一种新型高效的抗菌药物,现已逐步应用于纺织、建筑、医疗等各个行业中。传统抗菌方法存在着安全性差、灭菌时间长、操作不方便等缺点,纳米抗菌剂具有使用安全、方便,稳定性好,抗菌谱广和抗菌效力强等优点。综述了纳米抗菌剂的发展概况,展望了纳米抗菌剂发展的主要趋势。     

有机高分子抗菌剂的制备及抗菌机理

综述了有机高分子抗菌剂的研究进展,分别对带有季铵盐、季鳞盐、有机锡、吡啶类、胍盐类、卤代胺类和壳聚糖衍生物类七种抗菌基团的有机高分子抗菌剂的合成及应用等方面作了评述.重点介绍了季铵盐与季鳞盐两种有机高分子抗菌剂的发展情况,对季铵盐和季鳞盐应用于抗菌剂领域的优劣进行了比较.介绍了近几年发展较快的几种有机高分子抗菌剂的制备...     

茶皂素―金属复合抗菌剂的制备及抗菌性能研究

通过抑菌环法探讨了茶皂素、金属离子、茶皂素―金属复合抗菌剂对大肠杆菌和金黄色葡萄球菌的抗菌活性,考察了茶皂素纯度、浓度、金属离子种类等因素对抗菌剂抗菌活性的影响。结果表明,茶皂素的抗菌活性与单一的金属离子的抗菌活性相当,茶皂素对大肠杆菌的最低抑制浓度为5 mg/mL,对金黄色葡萄球菌的最低抑制浓度是10 mg/mL;茶皂素与金属离子复配抗菌活性具有协同效应,尤其茶皂素―锌复合抗菌剂对大肠杆菌的抑制效果大大加强。     

一种新型胍盐抗菌剂的制备及其性能研究

采用盐酸胍盐、六亚甲基二胺、二乙基三胺和环氧氯丙烷为原料合成了一种新型的胍盐抗菌剂,使其同时起到抗菌和提高纸页湿强度的作用。用二维核磁共振谱(HH-COSY)对胍盐抗菌剂的结构进行了表征,同时研究了胍盐抗菌剂对大肠杆菌的最低抑菌浓度和对纸张的增湿强效果。通过UV吸收法和激光共聚焦显微镜对胍盐抗菌剂的抗菌机理进行了进一步的研究,结果表明,胍盐抗菌剂主要是通过先破坏细菌的细胞膜,然后引起细胞内的物质流出细胞,从而抑制细菌的生长繁殖。     

含胍基抗菌聚合物的合成及应用

开发能与细菌非特异性结合的新型抗菌剂是解决细菌感染难题的方法之一。本文首先介绍了一种具有持久广谱高效抗菌性、无真核细胞毒性和细菌很难产生耐药性的含胍基抗菌聚合物;接着详细介绍了含胍基抗菌聚合物与细菌非特异性静电结合的抗菌机理;然后重点评述了主链含胍基抗菌聚合物、侧链含胍基抗菌聚合物以及表面接枝含胍基抗菌聚合物的设计理念、合成方法和抗菌性能;最后对新型含胍基抗菌聚合物的可控合成策略及应用前景进行了展望。     

抗菌聚合物合成及其抑菌性能的研究进展

抗菌聚合物作为新型的抗菌剂,其可控的结构和多样化的合成方式使其有很好的抗菌活性和应用前景。介绍了抗菌聚合物的合成方法及影响抗菌活性的主要因素、抗菌聚合物抗菌效果与聚合物结构的关系,为制备高活性的抗菌聚合物提供有益的参考,综述了新型抗菌材料的研究现状和发展趋势。     

Quantitative evaluation of antibacterial activities of nanoparticles (ZnO,TiO2, ZnO/TiO2, SnO2, CuO,ZrO2, and AgNO3) incorporated into polyvinyl butyral nanofibers

Novel hybrid polyvinyl butyral nanofibers have been developed for antimicrobial applications. The nanofiber mats were obtained from a needleless rod electrospinning system. The novel inorganic antibacterial agents were incorporated into the nanofibers, and their antibacterial activity was compared. The obtained nanoparticle/nanofiber hybrid mats have a good surface morphology. The results indicated that the CuO, ZnO, ZnO/TiO₂, and AgNO₃ nanoparticle‐incorporated nanofiber layers have excellent antibacterial activity against to Escherichia coli compared with TiO₂, SnO₂, and ZrO₂ ones. Copyright © 2016 John Wiley & Sons, Ltd.     

Impact of Electrospinning Parameters and Post-Treatment Method on Antibacterial and Antibiofilm Activity of Chitosan Nanofibers

Chitosan, a natural biopolymer, is an ideal candidate to prepare biomaterials capable of preventing microbial infections due to its antibacterial properties. Electrospinning is a versatile method ideally suited to process biopolymers with minimal impact on their physicochemical properties. However, fabrication parameters and post-processing routine can affect biological activity and, therefore, must be well adjusted. In this study, nanofibrous membranes were prepared using trifluoroacetic acid and dichloromethane and evaluated for physiochemical and antimicrobial properties. The use of such biomaterials as potential antibacterial agents was extensively studied in vitro using Staphylococcus aureus and Escherichia coli as test organisms. The antibacterial assay showed inhibition of bacterial growth and eradication of the planktonic cells of both E. coli and S. aureus in the liquid medium for up to 6 hrs. The quantitative assay showed a significant reduction in bacteria cell viability by nanofibers depending on the method of fabrication. The antibacterial properties of these biomaterials can be attributed to the structural modifications provided by co-solvent formulation and application of post-treatment procedure. Consequently, the proposed antimicrobial surface modification method is a promising technique to prepare biomaterials designed to induce antimicrobial resistance via antiadhesive capability and the biocide-releasing mechanism.     

Processing and Properties of Nanocomposite Filament Yarns with Various Filler Concentrations from Two Different Modification Methods

In this research, the possibility of producing and processing nanocomposite polypropylene filament yarns with permanent antimicrobial efficiency has been assessed by comparing two different methods. Therefore two approaches were used to mix various blending contents of antimicrobial agents based on silver/TiO₂ nano particles with PP: 1) mixing of PP powder and inorganic nanocomposite powder as an antibacterial agent with the appropriate concentration in a twin screw extruder, preparing modified granules and feeding them to the melt spinning machine, 2) producing masterbatch by a twin screw extruder and blending it with PP in the melt spinning process. In both methods, pure PP and all other combined samples had an acceptable spinnability at the spinning temperature of 240 °C and take-up speed of 2000 m/min. After producing as-spun filament yarns by a pilot plant melt spinning machine, samples were drawn, textured and finally weft knitted. Physical and structural properties of as-spun and drawn yarns with constant and variable draw ratios were investigated and compared. Moreover, the DSC, SEM and FTIR techniques have been used for samples characterization. Finally antibacterial efficiency of knitted samples was evaluated. The experimental results indicated that the maximum crystallinity reduction of modified as-spun yarns reached 5%. But by applying method 2 (masterbatch), crystallinity of modified as-spun yarns remained unchanged compared to pure yarn. However, drawing procedure has compensated this difference. By applying the second method, the drawing generally improved the increase of tenacity and modulus of modified fibers, whereas in method 1 the opposite effect was noticed in the case of constant draw ratio. Although the biostatic efficiency of nanocomposite fibers was excellent in both methods, modified fabrics obtained from method 1 showed higher bioactivity.     

Novel antibacterial fibers of amphiphilic N‐halamine polymer prepared by electrospinning

As a significant role in subcategory of halogen antibacterial field, amphiphilic N‐halamine polymers show a promise as potential antimicrobials having a broad spectrum of microorganisms, long‐term stability, and renewal of their antibacterial properties. By controlling the process parameters, electrospinning has been well recognized as a versatile and effective method being capable of making fibers and could be easily engineered with desired pore size and porosity to enhance the antimicrobial properties. The amphiphilic N‐halamine P (ADMH‐MMA‐HEMA) terpolymer fibers showed efficient antimicrobial properties against both Gram‐positive and Gram‐negative bacteria within brief contact time. The result meant that the polymer fibers of macromolecular architecture with control of structural parameters such as hydrophobicity/hydrophilicity balance achievement improved antimicrobial activities via electrospinning technique. In vitro cytotoxicity study demonstrated that the polymer was biocompatible. As a result, the integration of amphiphilic antibacterial materials and the electrospinning technique provided us a feasible method to fabricate biocompatible antimicrobial products easily with low manufacturing cost and would be applied in many promising application areas.     

Modification of natural fibers from Thespesia lampas plant by in situ generation of silver nanoparticles in single-step hydrothermal method

Ligno-cellulosic fibers have a great market and propose higher value addition and options to develop various products but they do not have inherent antimicrobial properties. In this study, a simple hydrothermal method was applied to build up antimicrobial properties to natural fibers by in situ-generating silver nanoparticles (AgNPs) in them. Herein, the ligno-cellulosic Thespesia lampas natural fibers were selected to develop antimicrobial activity using silver nitrate (AgNO₃) solution by hydrothermal method. The modified fibers were characterized by SEM, FTIR, XRD, TGA, and antibacterial activity tests. The modified fibers had spherical AgNPs with an average size of 95?nm. The thermal stability of the modified fibers was higher than that of the unmodified fibers. The modified fibers exhibited good antibacterial activity against both the Gram negative and Gram positive bacteria. These modified fibers can be considered as fillers in polymer matrices to make antibacterial composites.     

Antibacterial Effects of Flavonoids and Their Structure-Activity Relationship Study: A Comparative Interpretation

According to the latest report released by the World Health Organization, bacterial resistance to well-known and widely available antibacterial drugs has become a significant and severe global health concern and a grim challenge to tackle in order to cure infections associated with multidrug-resistant pathogenic microorganisms efficiently. Consequently, various strategies have been orchestrated to cure the severe complications related to multidrug-resistant bacteria effectively. Some approaches involved the retardation of biofilm formation and multidrug-resistance pumps in bacteria as well as the discovery of new antimicrobial agents demonstrating different mechanisms of action. In this regard, natural products namely alkaloids, terpenoids, steroids, anthraquinone, flavonoids, saponins, tannins, etc., have been suggested to tackle the multidrug-resistant bacterial strains owing to their versatile pharmacological effects. Amongst these, flavonoids, also known as polyphenolic compounds, have been widely evaluated for their antibacterial property due to their tendency to retard the growth of a wide range of pathogenic microorganisms, including multidrug-resistant bacteria. The hydroxylation of C5, C7, C3′, and C4′; and geranylation or prenylation at C6 have been extensively studied to increase bacterial inhibition of flavonoids. On the other hand, methoxylation at C3′ and C5 has been reported to decrease flavonoids’ antibacterial action. Hence, the latest information on the antibacterial activity of flavonoids is summarized in this review, with particular attention to the structure–activity relationship of this broad class of natural compounds to discover safe and potent antibacterial agents as natural products.     

稀土、钼酸、糠醛缩水杨酰肼三元配合物的合成、 表征及生物活性的研究

通过回流冷凝法和低温固相法制备了8种稀土、钼酸、糠醛缩水杨酰肼三元配合物, 并通过元素分析, 摩尔电导, IR, UV-vis, TG-DTA, TC-ICP, XRD, XPS对其结构和化学组成进行表征, 确定其化学组成为Re(HL)MoO4Cl•6H2O (HL: 糠醛缩水杨酰肼), 通过抑菌实验表明所制备的三元化合物对大肠杆菌和金黄色葡萄球菌具有中等抑制作用, 属于广谱抗菌剂; 通过MTT比色法对配合物使癌细胞凋亡能力做了初步研究, 结果表明, 三元配合物的IC50在10～100 ng/mL之间, 对癌细胞具有较强的抑制杀伤作用, 具有潜在的药物应用价值.     

Microwave-assisted synthesis of water-soluble styrylpyridine dye-capped zinc oxide nanoparticles for antibacterial applications

ZnO nanoparticles were successfully synthesized using a microwave method, whose surface was modified with {4-[(E)-2-(furan-2-yl)ethenyl]pyridin-1-ium-1-yl}acetate as a capping agent (1 and 3%). Their structural properties were investigated using FTIR, XRD, SEM, EDS, and UV–visible spectroscopy. XRD confirmed the Wurtzite structure for all compounds, a size of 30.6 nm for uncapped and 22.9 nm for 3% dye-capped nanoparticles were calculated from Scherer's equation. Hexagonal wurtzite shape of nanoparticles can be clearly seen in the SEM images. The DFT calculations were carried out using quantum espresso. These dye-capped ZnO nanoparticles were proved to be potential antibacterial agents, the minimum concentrations of dye-capped ZnO nanoparticles that inhibit the growth of bacteria are 1.5 mg/mL for Escherichia coli and 0.78 mg/mL for Bacillus subtilis, which are much lower than those of uncapped ZnO. The bioactivity data suggest these organic–inorganic hybrid nanoparticles emerged as a new class of antibacterial agents.     

Bio-Organometallic Derivatives of Antibacterial Drugs

Overuse and misuse of antibacterial drugs has resulted in bacteria resistance and in an increase in mortality rates due to bacterial infections. Therefore, there is an imperative necessity of new antibacterial drugs. Bio-organometallic derivatives of antibacterial agents offer an opportunity to discover new active antibacterial drugs. These compounds are well-characterized products and, in several examples, their antibacterial activities have been studied. Both inhibition of the antibacterial activity and strong increase in the antibiotic activity of the parent drug have been found. The synthesis of the main classes of bio-organometallic derivatives of these drugs, as well as examples of the use of structure–activity relation (SAR) studies to increase the activity and to understand the mode of action of bio-organometallic antimicrobial peptides (BOAMPs) and platensimicyn bio-organometallic mimics is presented in this article.