载铜蒙脱石的制备与表征

以蒙脱石和硫酸铜为主要原料,制备载铜蒙脱石。比较载铜前后蒙脱石的晶体结构和表面特性。结果表明：铜主要是以水合阳离子的形式,以离子交换的方式进入蒙脱石品格层间,还有少量铜以化学吸附的形式进入Si-O四面体和Al-O八面体的微孔中。与蒙脱石相比,载铜后的蒙脱石总比表面积、微孔比表面积、微孔体积减少,而离子交换容量、外比表面积、孔体积和孔径增大。另外,载铜蒙脱石的总电荷、层间电荷、端面电荷和zeta电位的绝对值均低于蒙脱石,表明所载铜降低了粘土矿物质的负电荷。     

直接从水玻璃合成表面修饰的纳米SiO2微粒

采用溶胶-凝胶法,以水玻璃为原料,在加入复合表面活性剂和分散剂的条件下,与乙酸反应直接得到纳米表面修饰的SiO2微粒。TEM照片显示,纳米SiO2颗粒为球形,粒度为10～30nm,统计平均粒径为20nm。合成工艺研究表明,纳米SiO2粒度大小和分散度大小可由表面活性剂浓度、反应物浓度、分散剂浓度和反应温度等控制,其中表面活性剂浓度、反应物浓度、分散剂浓度、反应温度的最佳值分别为：0．6mmol／L,0．6mol／L,7mmol／L,55℃。     

4种壬菌铜细菌专用配方的抑菌活性筛选

采用抑菌圈法测定4种壬菌铜细菌专用制剂对白菜软腐病菌和水稻向叶枯病菌室内毒力,结果表明：壬菌铜细菌专用1号、2号、3号均对白菜软腐病菌有不同程度的抑制作用;1号和2号均对水稻白叶枯病菌有抑制活性。其巾壬菌铜细菌专用1号对供试的2种病菌的抑制作用最显著,EC50分别为30．66mg／L和46．25mg／L。     

铜型抗菌层状硅酸盐的合成研究

采用液相离子交换法,将抗菌铜离子与钠基蒙脱石合成抗菌层状硅酸盐材料。研究了溶液浓度、pH值及反应时间等对合成抗菌材料中铜离子含量的影响。通过正交试验确定合成铜型抗菌层状硅酸盐的较佳反应条件为:CuCl2溶液的浓度0 1mol·L-1,在自然pH值下反应约1h。实验还测定抗菌层状硅酸盐的抗菌性能:铜型抗菌层状硅酸盐抗大肠杆菌、金黄色葡萄球菌等细菌性能良好,但抗霉菌性能一般。     

蒙脱石在医药中的应用

蒙脱石因其特殊的晶体结构而具有良好的吸附能力、阳离子交换能力和吸水膨胀能力。蒙脱石药理研究表明，它对大肠杆菌、霍乱弧菌、空肠弯曲菌、金黄色葡萄球菌和轮状病毒以及胆盐都有较好的吸附作用；对细菌毒素有固定作用；蒙脱石只吸附、固定表面带有粒编码蛋白（CS31A）的致病性带电病原菌，对表面不带CS31A的正常菌群无固定清除作用。因此，蒙脱石在医药上得到广泛应用。     

载银纳米二氧化钛的制备及抗菌性能研究

以碳酰二胺为沉淀剂与TiOSO4溶液反应生成Ti(OH)2沉积于AgCl晶种表面制备载银纳米二氧化钛,产物对金黄色葡萄球菌(S.aureus)、大肠杆菌(E.coli)和白色念珠菌(C.albicans)达到99%抗菌率的最小浓度分别是90、70、60 mg/L,经电子透射显微镜(TEM)表征,粒径主要分布于100～200 nm。     

1H-吲哚亚甲基氨基硫脲席夫碱铜（Ⅱ）配合物及其涂层的抗菌性研究

选用具有生物活性的吲哚-3-甲醛与氨基硫脲制备了席夫碱及其铜（Ⅱ）配合物,通过核磁共振氢谱、红外及紫外光谱等手段鉴定了其结构并确认配合物的配位方式。选用金黄色葡萄球菌（S. aureus）与大肠埃希氏菌（E. coli）测试了席夫碱及其铜（Ⅱ）配合物的抗菌性。结果表明：所制备的铜（Ⅱ）配合物对革兰氏阳性与革兰氏阴性菌均具有较好的抗菌效果,对金黄色葡萄球菌（S. aureus）和大肠埃希氏菌（E. coli）的最小抗菌浓度分别为0.40 g/L和0.95 g/L,具备广谱抗菌性。以吲哚甲醛氨基硫脲席夫碱铜（Ⅱ）配合物作为抗菌剂制备的抗菌涂层同样具有良好的抗菌效果,质量分数为5%时就能够杀灭抗菌涂层上黏附的大肠埃希氏菌（E. coli）。通过电镜观察细菌形貌推测吲哚甲醛氨基硫脲席夫碱铜（Ⅱ）配合物可能通过直接作用于细胞膜将其杀灭,具有较优的抗菌性。     

卡松对几种重要植物病原菌的抑制活性

在实验室条件下，分别测定了1．5％卡松对棉花枯萎病菌、棉花红腐病菌、棉花红粉病菌、棉花黄萎病菌和棉花疫病菌等5种重要植物病原真菌及水稻白叶枯病菌、大白菜软腐病菌等两种重要植物病原细菌的抑制活性。结果表明，1．5％卡松对棉花枯萎病菌的MIC和EC50分别为40mg/L和9．2034mg／L，对棉花红腐病菌的MIC和EC50分别为40mg／L和0．7845mg／L，对棉花红粉病菌的MIC和EC50分别为20mg／L和0．6951mg／L，对棉花黄萎病菌的MIC和EC50分别为20mg／L和2．8383mg／L，对棉花疫病菌的MIC和EC50分别为2mg／L和0．3459mg／L；对水稻白叶枯病菌和大白菜软腐病菌的MIC分别为1mg／L和10mg／L；说明该药剂对供试7种植物病原菌均具有良好的抑制活性，尤以对棉花疫病菌和水稻白叶枯病菌的抑制活性较强。     

载铜无机抗菌剂的制备及性能

以天然麦饭石为载体、铜离子为抗菌离子,在一定条件下通过液相离子交换反应,制备载铜麦饭石抗菌剂.运用ICP和XRD等现代分析方法对抗菌剂中银离子的含量以及银离子与载体的结合方式进行了分析,并对其抗菌性、耐久性和安全性能进行研究.结果表明,在Cu2+浓度是0.1 mol·L-1,搅拌时间是4 h,反应温度是60 ℃时,制备的麦饭石抗菌剂具有优异抗菌性、耐久性和安全性.究其原因主要在于Cu2+能从载体上缓慢地释放出来,与细菌细胞作用,杀灭细菌,从而赋予该抗菌剂良好的、持久的抗菌能力.     

UV/TiO2悬浮体系光催化降解碱性品红及机理研究

研究了在UV／TiO2悬浮体系中光催化降解碱性品红。考察了碱性品红浓度、悬浮液pH值和外加无机盐对降解效果的影响。实验结果表明,当碱性品红质量浓度分别为20．0mg／L,30．0mg／L,40．0mg/L时,光照180min后,悬浮液中剩余的碱性品红质量浓度分别为1．8mg／L,2．3mg／L,3．4mg／L。pH=9．00时降解效果最好,当初始碱性品红质量浓度为30mg/L时,光照180min后,悬浮液中剩余的碱性品红质量浓度为0．8mg／L;pH=3．00的降解效果最差,光照180min后,悬浮液中剩余的碱性品红质量浓度为6．8mg／L;无机盐对降解效果有不同程度的负面影响。对降解机理的探讨表明光催化反应发生在光催化剂表面。     

吴茱萸柠檬苦素提取物的抑菌效果研究

采用稀释法研究了吴茱萸柠檬苦素提取物的最低抑菌浓度（MIC）和最低杀菌浓度（MBC）,并采用滤纸片法对吴茱萸柠檬苦素提取物和吴茱萸的醇提物的抑菌活性进行了对比研究。试验结果表明吴茱萸柠檬苦素提取物对藤黄微球菌、沙门氏菌、痢疾志贺氏菌、柠檬酸杆菌的抑菌效果及杀菌效果较好,其中吴茱萸柠檬苦素提取物的抑菌杀菌效果明显高于同浓...     

Antibacterial Activity of Poly(aniline-co-ethylaniline) against Staphylococcus aureus and Pseudomonas aeruginosa

This study describes the preparation of colloidal poly(aniline-co-ethylaniline) by chemical copolymerization. The product was characterized morphologically using scanning electron microscope and transmission electron microscopy, chemically using Fourier transform infrared spectroscopy and optically ultraviolet–visible spectroscopy. The prepared polymer was then tested for the antibacterial properties against Gram-negative bacteria; Pseudomonas aeruginosa and Gram-positive bacteria; Staphylococcus aureus. The antibacterial properties were assessed by disk diffusion, minimum inhibitory concentration, minimum bactericidal concentrations, and bactericidal kinetic methods. It was found that the minimum inhibitory concentration and minimum bactericidal concentrations values of poly(aniline-co-ethylaniline) against P. aeruginosa were 0.62 mg/ml and 1.25, respectively. The values of minimum inhibitory concentration and minimum bactericidal concentrations for S. aureus were 0.62 mg/ml.     

Cu~(2+)-膨润土的制备、结构及性能研究

研究了天然膨润土的提纯,钠化改型及Cu2+-膨润土的制备,比较了不同的钠化剂对钠化土的蒙脱石含量,离子交换容量的影响。结果表明,天然膨润土提纯后蒙脱石的含量增加;采用焦磷酸钠为钠化剂进行溶液交换的钠化效果最佳;悬浮体系酸、碱浓度适中时(pH=4~11),Cu2+-膨润土表现出对酸、碱的缓冲作用,pH值保持在4.76左右。     

季铵盐改性蒙脱土的抗菌活性及抗菌机理

采用离子交换法将不同季钱盐插层到钠基蒙脱土中制备了改性蒙脱土.改性蒙脱土对革兰氏阳性菌(S.aereus)和革兰氏阴性菌(E coli)均有很强的抗菌作用,并且随着季铵盐在蒙脱土中的质量分数增加其抗菌活性增强.不同季铵盐改性蒙脱土的抗菌活性不同,其中双季铵盐改性蒙脱土的抗菌活性最好,对S.aereus和E coli的最小抑菌浓度分别为6.25 mg/L和12.5 mg/L.用扫描电镜对与细菌接触不同时间后的改性蒙脱土进行观察,结果表明:细菌先吸附到改性蒙脱土的表面,然后慢慢的变形死亡.同时,对在0.9%的生理盐水中浸泡不同时间后的改性蒙脱土进行X射线衍射和热重分析.结果表明:随着浸泡时间的增加,蒙脱土中的有机物质量分数及层间距均逐渐减少,说明季铵盐能从蒙脱土的层间解吸出来,并进入溶液中直接杀死细菌.因而,改性蒙脱土的抗菌活性是吸附与释放到溶液中的季铵盐离子协同作用的结果.     

Cu2+-TiO2/蒙脱石自净化功能基元材料

以蒙脱石为载体,通过溶液离子交换以及高温灼烧法,将具有抗菌活性的Cu^2 固载到载体的孔道中,同时将具有光催化降解自净化功能的TiO2插入到硅酸盐的层问,得到了对大肠杆菌(8099)和金黄色葡萄球菌(ATCC6538)抗菌率为99．99％、光催化降解亚甲基蓝溶液的净化率为92．65％的自净化功能基元材料Cu^2 -TiO2/蒙脱石(Cu^2 -TiO2-M)。     

Cu2+/ZnO-蒙脱石抗菌材料的制备及抑菌活性研究

以Cu(NO3)2、ZnCl2、NaOH为主要原料,蒙脱石(MMT)作为载体,制备Cu2+/ZnO-MMT抗菌材料,并对其结构、表面性质和抑菌性能进行表征.结果表明,Cu2+/ZnO-MMT对大肠杆菌和金黄色葡萄球菌均具有较强的抑菌活性.以大肠杆菌为试验菌种,研究了所制材料的杀菌机理,首先大肠杆菌被吸附到蒙脱石表面,然后细菌细胞质膜被所载的Cu2+和ZnO损伤,使胞内溶物外流,最终细菌死亡.     

Activity of antibacterial compounds immobilised on montmorillonite

The activities of antibacterial compounds, such as cetylpyridinium (CP), cetyltrimethylammonium (CTA), silver ions and metallic silver, immobilised on montmorillonite (MMT), were tested in Escherichia coli and Enterococcus faecium bacteria. The results of bacterial growth tests were confirmed by determination of the minimum inhibition concentrations (MICs). Unlike CP and CTA, the intercalated silver ions were easily released from MMT by ion-exchange with Na⁺ and acted as very effective antibacterial substances in the long term. Their bactericidal and bacteriostatic effects were determined. Generally, antibacterial compounds are effective when they are released from an inorganic carrier. Metallic silver was prepared by reduction of intercalated Ag⁺ with sodium borohydride. Antibacterial effects of metallic silver were not observed.     

Influence of ethanol addition on the modification of montmorillonite by hexadecyl trimethylammonium bromide

Although modification of montmorillonite (MMT) with cationic surfactants has been studied extensively, the influence of the reaction medium has not been investigated systematically. The present paper reports the influence of ethanol on the modification of MMT using hexadecyl trimethylammonium bromide (HDTMA-Br). Wide angle X-ray diffraction (WAXD) and thermogravimetric analysis (TGA) were used to characterize the organically modified montmorillonite (OMMT). The addition of ethanol had little influence on the cation exchange, but affected greatly on the intercalation of the surfactant ion pairs into the interlayer space when HDTMA exceed the cation exchange capacity (CEC) of MMT. The increase of the ethanol/water ratio increased the critical micelle concentration (CMC) of HDTMA-Br solution. The intercalation of HDTMA ion pairs proceeded when the HDTMA concentration was above the CMC. It was confirmed that both of basal spacing and organic fraction followed sigmoid functions for OMMT prepared with excess HDTMA-Br amount and various surfactant concentrations under different CMC.     

Antimicrobial Activity of Isothiocyanates from Cruciferous Plants against Methicillin-Resistant Staphylococcus aureus (MRSA)

Purified isothiocyanates from cruciferous plants (Brassicacea, Syn. Cruciferae) plants were evaluated against 15 isolates of methicillin-resistant S. aureus isolated from diabetic foot-ulcer patients aiming the study of the potential usage of allyl-isothiocyanate, benzyl-isothiocyanate and 2-phenylethyl-isothiocyanate against this important bacteria. Disc diffusion and minimum inhibitory concentration methods were used to access the antimicrobial activity. The index (Ia) and rate (Ra) of the antibacterial activity for each compound were calculated. The results showed a highly dose-dependent compound and chemical structure antibacterial effectiveness. The results showed a strong relation between the chemical structure of isothiocyanates and its antibacterial effectiveness. The benzyl-isothiocyanate was the most effective with a minimum inhibitory concentration varying between 2.9 and 110 µg· mL⁻¹ with an antibacterial activity rate up to 87%. Moreover, their antibacterial activity was mainly bactericidal. This study provides scientific evidence that isothiocyanates have an interesting biological value and must be considered as an important tool to be used against MRSA.     

二氧化钛/蒙脱石复合光催化剂抗菌动力学研究

以大肠杆菌和金黄色葡萄球菌为模型微生物,研究了TiO2/蒙脱石复合光催化剂的抗菌性能。分析了光照射方式、细菌接种世代对光催化抗菌效果的影响,并从悬菌液初始浓度、催化剂用量和缓冲液三方面考察了反应的动力学行为。实验结果表明,75 min内,TiO2/蒙脱石对两种细菌的灭菌率均达到99%左右;间歇光照射与连续光照射时的抗菌效果较为接近;细菌接种世代越多,其对光催化作用的敏感性越强。当菌液浓度为103~107cfu/mL时,TiO2/蒙脱石光催化抗菌反应符合表观拟1级反应动力学模型;催化剂用量与反应速率常数呈二次抛物线关系;使用不同的缓冲液,抗菌反应速率由大到小的顺序为:PBS(磷酸盐缓冲液)<生理盐水<无菌蒸馏水。