口腔纳米载银无机抗菌材料的抗菌性能

背景：纳米载银无机抗菌剂具有抗菌谱广、抗菌能力强等特点,是目前口腔无机抗菌材料研究的热点之一。 目的：研究纳米载银无机抗菌材料的抗菌性能及抗菌机制,为基础实验研究和临床应用提供参考信息。 方法：研究多种口腔纳米载银无机抗菌材料对常见病原菌如变形链球菌、白色念珠菌以及粘性放线菌等的抗菌性能,其中包括最低杀菌浓度以及抗菌率等,同时进行对比分析。并且研究纳米载银无机抗菌材料的抗菌机制,明确其优点与不足。 结果与结论：口腔纳米载银无机抗菌材料具有较广的抗菌谱,对变形链球菌、乳酸杆菌、粘性放线菌、白色念珠菌、牙龈卟啉单胞菌、金黄色葡萄球菌以及大肠埃希菌等均具有较强的抗菌性能,最低杀菌浓度较低,而抗菌率较高。但是同一纳米载银无机抗菌材料对不同的病原菌,其最低杀菌浓度不同,抗菌率也不同,而不同的纳米载银无机抗菌材料对同一病原菌的最低杀菌浓度也不相同,抗菌率也不同。     

P型纳米二氧化硅载银抗真菌耐高温及稳定性试验的研究

目的:研究P型纳米二氧化硅载银抗菌粉抗真菌效果及耐热性和稳定性。方法:(1)测定不同浓度,不同作用时间的抗真菌率。(2)耐高温和稳定性测试。结果:P型纳米二氧化硅载银抗菌粉浓度越高抗真菌效果越好,作用时间越长抗真菌效果越好。最小抑菌浓度,P型纳米二氧化硅载银抗菌粉(含银0.35%)1 g 5 mL水与白色念珠菌作用20分钟平均抑菌率可达70.21%。P型纳米二氧化硅载银抗菌粉置于94℃电热恒温水浴锅中放置14天后,配制浓度为1 g 5 mL的药液与白色念珠菌作用20分钟,抗真菌率仍可达到56.25%。结论:P型纳米二氧化硅载银抗菌稳定性很好,耐高温、不失效。     

纳米氧化锌对白色念珠菌的抗菌作用

背景：纳米氧化锌作为无机抗菌剂,与有机杀菌剂的抗菌机制明显不同。 目的：探讨纳米氧化锌对白色念珠菌等真菌的抗菌作用。 方法：分别配制成100,75,50,25,10 g/L的纳米氧化锌与普通氧化锌悬浊液,以生理盐水作为阴性对照,采用KB纸片扩散法将30 μL不同浓度悬浊液分别作用于白色念珠菌,将培养平板上置于37 ℃恒温箱培养24 h观察并测量抑菌圈大小。 结果与讨论：随着纳米氧化锌浓度的提高,对白色念珠菌的抑制作用逐渐增强,抑菌圈直径逐渐增大。普通氧化锌的无明显抑菌作用。证实纳米氧化锌能够抑制白色念珠菌等真菌的生长。     

纳米载银磷酸锆抗菌聚氨酯的抗菌性能****

背景：聚氨酯材料具有优异的物理和化学性能,良好的生物相容性和抗凝血性能,且易加工成形,但聚氨酯制造的人工器官容易受到细菌等微生物的入侵。 目的：观察纳米载银无机抗菌剂对聚氨酯抗菌性能的影响。 方法：将纳米载银无机抗菌剂RHA-2,按0%(空白对照组),0.5%,1%,1.5%,2%,2.5%,5%比例添加到聚氨酯中。采用薄膜密着法检测抗菌聚氨酯对金黄色葡萄球菌、大肠杆菌的抑菌作用,并分析比较抗菌剂添加比例与聚氨酯抗菌性能的相关性。 结果与结论：添加纳米载银无机抗菌剂的聚氨酯对金黄色葡萄球菌、大肠杆菌具有良好的抑菌作用。抗菌剂添加比例0.5%~5%组对金黄色葡萄球菌的抑菌率分别为80.23%,91.32%,95.23%,99.19%,99.87%,99.93%,对大肠杆菌的抑菌率分别为76.70%,86.96%,92.92%,95.43%,99.34%,99.87%,显示抗菌性能随抗菌剂添加比例的上升而明显提高。表明纳米载银无机抗菌剂的添加赋予了聚氨酯优异的抗菌性能,且从抗菌角度出发,推荐纳米载银无机抗菌剂在聚氨酯中的添加比例不应低于1.5%。     

几种常用载银抗菌材料改性方式的研究现状

背景：银系抗菌剂具有生物安全性高,抗菌谱广,不产生耐药性等特点,是口腔无机抗菌剂中研究的热点。 目的：围绕几种常用银系无机抗菌剂载体结构、载银原理及对其载银方式、载银环境等改性增强其抗菌效果和改善原材料缺陷的研究现状作以综述。 方法：应用计算机检索CNKI数据库、OVID数据库2000/2010有关银系抗菌剂及其载体的相关文章。 结果与结论：无论是传统的沸石、磷酸盐等载体,还是新型的纳米载银方式,人们都从材料本身特征及其载银特质方面不断改性,以期得到用量更少,抑菌性能更优及克服了变色等性能缺陷的优质载银抗菌剂。以后载银无机抗菌材料的开发,除了可以更进一步地利用纳米载银以外,还可以往复合抑菌,缓释抑菌以及将抑菌作为其他材料的添加辅助性能等方面发展。     

LZB-GC纳米载银抗菌剂在藻酸盐印模材料中的抗菌性

背景：关于藻酸盐印模材料的消毒方法一直存在争议。 目的：分析LZB-GC纳米载银抗菌剂在藻酸盐印模材料中的最佳添加比例。 方法：将LZB-GC抗菌剂分别以0.125%,0.25%,0.5%,1%,1.5%,2%,2.5%的比例添加到藻酸盐印模材料中,以未添加LZB-GC抗菌剂的藻酸盐印模材料为对照,采用薄膜密着法测试其对金黄色葡萄球菌和大肠杆菌的抗菌性能。 结果与结论：随着LZB-GC抗菌剂添加量的增加,对金黄色葡萄球菌和大肠杆菌的抗菌率随之增大(P < 0.05),当添加量达到0.5%及以上,抗菌率可达到99%以上。说明LZB-GC抗菌剂在藻酸盐印模材料中的最佳添加比例为0.5%。     

纳米氧化锌抗菌性能及机制*◆

 背景：氧化锌作为一种活性氧化物类抗菌材料,拥有良好的生物相容性、安全性以及长效性。目的：总结纳米氧化锌的抗菌性能及其抗菌机制。方法：应用计算机检索1995-12/2011-02 Elsevier (ScienceDirect)及Web of Science期刊引文索引数据库相关文章,检索词为“antibacterial properties of nano-zinc oxide”,并限定文章语言种类为English。同时计算机检索1995-12/2011-02 CNKI学术总库及万方数据库相关文章,检索词为“纳米氧化锌抗菌性能”,并限定文章语言种类为中文。共检索到文献75篇。结果与结论：纳米氧化锌在很多方面的杀菌性能都很强,并且由于其良好的生物相容性、安全性以及长效性,可以取代医学上其他活性氧化物抗菌材料。文章从纳米氧化锌抗菌性能改性,以及形貌与结构对抗菌性的影响等方面,详细总结了纳米氧化锌的抗菌性能及其抗菌机制,但是如何提高纳米氧化锌的利用率和杀菌性能,如何使纳米氧化锌应用于更多细菌的抑制或更广阔的领域,都需要人们的继续努力。关键词：纳米氧化锌;抗菌材料;抗菌机制;生物材料;综述文献 doi:10.3969/j.issn.1673-8225.2012.03.033      

中性粒细胞防御素对致病酵母菌的抗菌活性

本实验用琼脂糖弥散抗菌试验检测兔中性粒细胞防御素NP-2和人中性粒细胞防御素HNP对白色念珠菌M1012R、白色念球菌NIH A-207、乳酒念珠菌、热带念珠菌、高里氏念珠菌等5株的抗菌活性。结果显示,在含菌琼脂平板试验孔中每孔加入156ng(31.25ug/ml×5μl)NP-2时即对上述5株真菌呈现显著抗菌活性。随着每孔加入NP-2量增多,其抗菌环直径增大。5株酵母菌对NP-2的敏感性依次为高里氏念珠菌、白色念珠菌M1012R、乳酒念珠菌、热带念珠菌、白色念珠菌NIH A-207。在试验孔中每孔加     

不同pH值纳米羟基磷灰石复合根充糊剂的体外抑菌性

背景：目前临床应用的根管充填糊剂抗菌作用有限,存在组织刺激性强、成形困难、根管封闭性较差及易降解等缺点。 目的：比较不同pH值纳米羟基磷灰石复合根充糊剂对感染根管常见菌的体外抑菌作用。 方法：建立体外根管粪肠球菌、白色念球菌感染模型,评价pH 8纳米羟基磷灰石糊剂、pH 9纳米羟基磷灰石糊剂、pH 10纳米羟基磷灰石糊剂在离体牙根管内的抗菌作用,并以氧化锌丁香油做对照。 结果与结论：所有根充糊剂均具有抑菌作用。各pH值纳米羟基磷灰石糊剂对粪肠球菌抑制作用实验组优于氧化锌丁香油组(P < 0.05),不同pH值纳米羟基磷灰石组组间比较差异无显著性意义(P > 0.05)。而对白色念珠菌抑制作用各pH值纳米羟基磷灰石组不及氧化锌丁香油组(P < 0.05),各pH值纳米羟基磷灰石组组间比较,pH10纳米羟基磷灰石组>pH 9纳米羟基磷灰石组>pH 8纳米羟基磷灰石组(P < 0.05)。结果表明,感染根管模型中,纳米羟基磷灰石根充糊剂对粪肠球菌的抑制作用好于氧化锌丁香油(P < 0.05),而对白色念珠菌的抑制作用不及氧化锌丁香油(P < 0.05)。pH=10纳米羟基磷灰石复合根充糊剂的抑菌作用最佳。     

纳米载银磷酸锆抗菌聚氨酯的细胞毒性检测

背景：聚氨酯是一种研究热门的医用高分子材料,并在许多人工器官和医疗装置中发挥着至关重要的作用。 目的：制备并观察纳米载银磷酸锆抗菌聚氨酯生物材料对L929细胞增殖活性的影响及细胞毒性反应。 方法：采用MTT法检测各组抗菌聚氨酯对传代培养小鼠成纤维细胞L929的细胞毒性,L929细胞接种于96孔板,随机分为3组进行培养,实验组用抗菌聚氨酯浸提液处理,阳性对照组用苯酚溶液,阴性对照组用高密度聚乙烯浸提液,于24,48,72 h后在倒置相差显微镜下观察细胞形态,通过MTT比色法检测各组细胞的相对增殖率,并评价材料的细胞毒性。 结果与结论：实验组作用于小鼠成纤维细胞24,48,72 h后,相对增殖率分别为94.3%~97.9%,94.5%~99.8%和90.8%~96.3%,材料细胞毒性评级为Ⅰ级。提示添加低浓度纳米载银无机抗菌剂RHA-2(添加比例<5%)的热塑性聚氨酯,无细胞毒性,符合医用生物材料安全标准。     

Synthesis and characterization of antibacterial dental monomers and composites

The objective of this study is to synthesize antibacterial methacrylate and methacrylamide monomers and formulate antibacterial fluoride-releasing dental composites. Three antibacterial methacrylate or methacrylamide monomers containing long-chain quaternary ammonium fluoride, 1,2-methacrylamido-N,N,N-trimethyldodecan-1-aminium fluoride (monomer I), N-benzyl-11-(methacryloyloxy)-N,N-dimethylundecan-1-aminium fluoride (monomer II), and methacryloxyldecylpyridinium fluoride (monomer III) have been synthesized and analyzed by nuclear magnetic resonance (NMR) and mass spectrometry (MS). The cytotoxicity test and bactericidal test against Streptococcus mutans indicate that antibacterial monomer II is superior to monomers I and III. A series of dental composites containing 0-6% of antibacterial monomer II have been formulated and tested for degree of conversion (DC), flexure strength, water sorption, solubility, and inhibition of S. mutans biofilms. An antibacterial fluoride-releasing dental composite has also been formulated and tested for flexure strength and fluoride release. The dental composite containing 3% of monomer II has a significant effect against S. mutans biofilm formation without major adverse effects on its physical and mechanical properties. The new antibacterial monomers can be used together with the fluoride-releasing monomers containing a ternary zirconiun-fluoride chelate to formulate a new antibacterial fluoride-releasing dental composite. Such a new dental composite is expected to have higher anticaries efficacy and longer service life.     

Study on the heat resistant property of Ag/4A antibacterial agent

The heat resistant property of silver-loading zeolite 4A antibacterial agent (SLZ) was investigated by heat treatment methodology. The morphological and structural changes of the specimens were characterized by using differential thermal analyzer (TG-DTA), scanning electron microscopy, and X-ray diffraction techniques. The particle size of the specimens was measured by Malvern instruments zetasizer systems, and silver content of specimens was determined by inductively coupled plasma spectrometer. Escherichia coli (E. coli) was chosen as indicators of fecal contamination to evaluate the antibacterial effect of the specimens by minimum inhibitory concentration method. The service life of the specimens was also tested. The experimental results indicated that as heat-treatment temperature increases, the particle size increases, more aggregating occurs, silver content decreases, the color of SLZ gradually changes from white to brown, and the antibacterial ability falls. The release rate of Ag(+) cation from SLZ became slow after heat treatment at 400, 450, and 500 degrees C, thus resulting in prolonged service life of SLZ. When the heat-treatment temperature approached 800 degrees C, the collapse of SLZ structure occurred, and the crystals of SiO(2) and Al(2)O(3) were formed after recrystallization. Consequently, the heat resistant temperature of SLZ can be as high as 500 degrees C. SLZ could be used in antibacterial plastics, antibacterial fibers, or biomedical materials.     

TiO2-xNx抗菌托槽的抑菌性能

 背景：有研究表明TiO_2-xN_x薄膜对变形链球菌、黏性放线菌及白色念珠菌具有良好的抗菌效果。目的：进一步评价TiO_2-xN_x薄膜托槽的抗菌性能。 方法：纳入10例正畸患者,将口内牙齿以上下中线分为左右两侧,分别粘接普通金属托槽和TiO_2-xN_x薄膜托槽,在矫治前、矫治后1,2,3,4周检测正畸菌斑指数、牙龈指数、龈沟出血指数及釉质脱矿指数。结果与结论：普通金属托槽组矫治后1,2,3,4周的正畸菌斑指数、牙龈指数、龈沟出血指数及釉质脱矿指数均高于矫治前(P < 0.05);TiO_2-xN_x薄膜托槽组矫治后3周的牙龈指数高于矫治前(P < 0.05),矫治后1,2,3周的龈沟出血指数高于矫治前(P < 0.05),矫治后2,3,4周的釉质脱矿指数高于矫治前(P < 0.05);TiO_2-xN_x薄膜托槽组矫治后1-4周的正畸菌斑指数、龈沟出血指数均低于普通金属托槽组(P < 0.05),矫治后2-4周的牙龈指数、釉质脱矿指数均低于普通金属托槽组(P < 0.05)。表明TiO_2-xN_x薄膜托槽具有较好的抗菌效果,可更好地控制和清除菌斑。中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

A facile method to construct hybrid multilayered films as a strong and multifunctional antibacterial coating

A multifunctional multilayered film containing TiO(2) nanoparticles as contact-active antibacterial agent and nanosilver as a release-active antibacterial agent was fabricated via layer-by-layer assembly. TiO(2) nanoparticles with the anatase crystalline dominant structure were synthesized via a sol-gel method. The QCM, AFM, and contact angle measurement results indicated that the TiO(2) nanoparticle-chitosan was successfully assembled with heparin via layer-by-layer assembly. The UV visible spectroscopy demonstrated that the silver ions could be loaded into the multilayers and in situ synthesize silver nanoparticles in the multilayers template. The short-term antibacterial assay showed the TiO(2)-chitosan/heparin multilayers loaded with nanosilver was bactericidal both in the low intensity UV light and in the dark. The long-term antibacterial assay indicated although the antibacterial in dark decreased with the PBS immersion time, the hybrid multilayered films sustained the long-term antibacterial in the low intensity UV light.     

Ag-TiO2抗菌树脂基托的生物毒性评价

背景：纳米Ag-TiO2抗菌剂结合金属Ag+与纳米TiO2的抗菌性能,具有抗菌广谱、长久性、耐高温、安全、经济等特点。 目的：评价Ag-TiO2抗菌树脂基托对人体的生物安全性。 方法：①口腔黏膜刺激实验：将含0(对照),0.5%,1.0%,1.5%,2.0%,3.0% 纳米Ag-TiO2抗菌剂的牙托粉缝合于成年金黄地鼠颊黏膜中14 d。②体外细胞毒性实验：将小鼠成纤维细胞L-929接种于含0(对照),0.5%,1.0%,1.5%,2.0%,3.0% 纳米Ag-TiO2抗菌剂的牙托粉浸提液中培养。 结果与结论：①黏膜刺激实验显示,与不同浓度抗菌树脂基托接触的颊黏膜与对照组切片无差异,未出现过敏或炎症反应。②细胞毒性实验证实,各浓度Ag-TiO2抗菌树脂基托无细胞毒性,毒性反应为0级。说明Ag-TiO2抗菌树脂基托符合中华人民共和国国家标准及相关的医药行业标准,对人体安全、无害,具有良好的生物相容性。     

Preparation and antibacterial activity of silver-loaded poly(oligo(ethylene glycol) methacrylate) brush

Herein, we report on a robust approach to fabricate antibacterial nanocomposite coating simply by immersing poly(oligo(ethylene glycol) methacrylate) (POEGMA) brush into a silver perchlorate solution without using any external reducing agents. The POEGMA brush of 48.3?nm in thickness is prepared via surface-initiated atom transfer radical polymerization method. Field-emission scanning electron microscope and Raman measurements indicate that silver nanoparticles of 14?～?25?nm in diameter are successfully embedded into the POEGMA brush. Antibacterial activities of the resultant silver-loaded POEGMA brushes against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus are measured by zone of inhibition and colony-counting methods, respectively. The results show that the silver-loaded POEGMA coatings exhibit enhanced antibacterial efficiency compared to bare POEGMA brush. In order to elucidate their antibacterial mechanism, silver release behaviors of these silver-loaded POEGMA brushes are monitored via inductively coupled plasma mass spectrometry.     

In situ formation of silver nanoparticles in photocrosslinking polymers

Nanocomposites of cross-linked methacrylate polymers with silver nanoparticles have been synthesized by coupling photoinitiated free radical polymerization of dimethacrylates with in situ silver ion reduction. A polymerizable methacrylate bearing a secondary amino functional group was used to increase the solubility of the silver salt in the hydrophobic resin system. Fourier transform infrared spectroscopy (FTIR) revealed that the silver ion reduction had no significant effect on the degree of vinyl conversion of the methacrylate. X-ray photoelectron spectroscopy (XPS) measurements showed an increased silver concentration at the composite surface compared to the expected concentration based on the total amount of silver salt added. Furthermore, the surface silver concentration leveled off when the silver salt mass fractions were 0.08% or greater. Composites with low concentrations of silver salt (< 0.08% by mass) exhibited comparable mechanical properties to those containing no silver. Transmission electron microscopy (TEM) confirmed that the silver nanoparticles formed within the polymer matrix were nanocrystalline in nature and primarily ≈ 3 nm in diameter, with some large particle aggregates. Composites containing silver nanoparticles were shown to reduce bacterial colonization with as little as 0.03% (by mass) silver salt, while additional amounts of silver salt did not further decrease their surface colonization. With a substantial effect on bacterial growth and minimal effects on mechanical properties, the in situ formation of silver nanoparticles within methacrylate materials is a promising technique for synthesizing antibacterial nanocomposites for biomedical applications.     

Antifungal and antibacterial properties of a silver-loaded cellulosic fiber

The skin is the interface between the body and the environment. Each skin type has a specific skin physiology and is more or less adapted for protection against multiple stress factors. Textiles on the other hand are the tissues with the longest contact to the human skin. They play a critical role especially in skin conditions with an increased rate of bacterial and fungal infections like atopic dermatitis and hyperhidrosis, and in diabetic patients and aged skin. The present study demonstrates the antifungal and antibacterial effects of SeaCell Active in an in vitro test system against Candida albicans (DSM 11225), Candida tropicalis (ATCC 1169), and Candida krusei (ATCC 6258). Furthermore, the antibacterial activity of fibers with different amounts of SeaCell Active fibers in a dose-dependent manner against Staphylococcus aureus (ATCC 22923) and Escherichia coli (ATCC 35218) could be demonstrated. If this fiber seems to be suited for bioactive textiles in specific anatomical regions and skin conditions with a susceptibility for fungal and bacterial infections due to Candida species, namely Staphylococcus aureus and Escherichia coli, must be examined by means of further investigations, especially in vivo tests in human, considering allergic and toxic effects of the fiber.