载银缓释型抗菌敷料

近10年来,载银缓释型抗菌敷料因其优良特性,在医药、卫生等领域引起科学家们的广泛关注。本文综述了银的抗菌机理和载银缓释型抗菌敷料的缓释机制;重点介绍了目前在国际市场上销售的代表性载银缓释型抗菌敷料的性能,并从不同的载体材料角度(如生物高分子、合成高分子、生物和合成高分子共用、有机硅材料)总结了新型载银抗菌敷料的研究进展;最后,讨论了载银抗菌医用敷料在研究和应用中需要解决的问题。     

纳米蒙脱石对海漂蛸和瓦楞子的缓释作用研究

研究了海螵蛸和瓦楞子及加入缓释剂后与人工胃液反应的速率,为延长制酸止痛的时间提供依据。利用压差计求出气体物质的量的变化⊿n为纵坐标,以时间t为横坐标作图,可直观地求出反应速率。结果表明,在上述两种药物中加入缓释剂蒙脱石后,它们与胃酸反应速率明显降低。从而达到延长制酸止痛时间的目的。     

壳聚糖/生发药物缓释膜的制备及性能

报道了壳聚糖生发药物缓释膜的制备、性能。确定了壳聚糖溶液成膜的最佳条件 ,用 3 5× 1 0 -5mol L壳聚糖溶液、0 2mol L的乙醇和少量甘油 ,制备的壳聚糖膜抗拉强度为 5 3 5 0 8N m。用UV分光光度法测定了生发药物缓释膜在水中的释放速率 ,对膜的缓释机理进行了初步探讨     

载药(甲磺酸帕珠沙星)水凝胶的制备及其药物缓释性能

以甲磺酸帕珠沙星(1)为药物,以壳聚糖修饰的多壁碳纳米管(MWCNT-CS)/壳聚糖半互穿网络水凝胶(C)为载体,采用浸泡法合成了不同MWCNT-CS含量(0%,2.5%,10.0%)的三种载药水凝胶[C0(1),C2.5(1)和C1000(1)].研究了C(1)中MWCNT-CS含量以及pH对1释放性能的影响.结果表...     

载银活性炭的制备与表征

在活性炭上负载银离子,制备具有抗菌性能的吸附材料载银活性炭.首先,优选了分散剂的种类为聚乙烯吡咯烷酮(PVP),得出PVP:银离子最佳质量比为1:1;其次,探讨了在不同碳化温度下改性活性炭载银量,未经碳化处理时载银量为17.09％,碳化温度为500℃时,载银量为18.24％;碳化温度800℃时,载银量增加到18.61％...     

Ni^2—交换蒙脱石中的镍物种及焙烧温度影响研究

对一组自制Ｎｉ＾２＋交换蒙脱石样品中镍物种的存在在形及焙烧温度影响进行了ＴＰＲ和ＸＲＤ考察结果表明，样品中镍负载量等于或小于Ｎｉ＾２＋的交换量时，镍主要以难还原听可交换性阳离子Ｎｉ（ＯＨ）＾ｑ＋ｘ和易还原的自由态镍Ｎｉ（ＯＨ）２或ＮｉＯ两种形式存在。     

载银离子PLGA-PEG-PLGA温度敏感水凝胶的制备及体外抗菌性能

利用聚乙二醇(PEG 1000)引发乙交酯和 D,L-丙交酯开环共聚合, 制备了聚丙交酯乙交酯(PLGA)三嵌段共聚物(PLGA-PEG-PLGA)温敏水凝胶材料; 利用核磁共振氢谱( ¹H NMR)确定了产物的结构及组成. 通过还原硝酸银的方法制备银纳米粒子(AgNPs), 并将其与PLGA-PEG-PLGA三嵌段共聚物水凝胶混合, 制得新型AgNPs/PLGA-PEG-PLGA复合水凝胶; 对该复合水凝胶的相关性能进行了表征. AgNPs/PLGA-PEG-PLGA复合水凝胶仍然具有温敏性能, 随着温度升高可发生溶胶-凝胶的相转变; 还可以持续释放银纳米粒子, 从而发挥抗菌性能. 体外细胞实验结果表明, AgNPs/PLGA-PEG-PLGA复合水凝胶具有良好的生物相容性, 未见明显细胞毒性, 是具有应用前景的新型复合水凝胶.     

合成云母蒙脱石的交联及其性能的研究

分别用十三铝低聚物和丙胺基三乙氧基硅烷与合成云母蒙脱石交联,制得了柱高分别为0.83和0.86 nm的交联云母蒙脱石Al-CLM和Si-CLM。按Si-O键长估算,硅柱可能由SiO_2的三聚物构成。IR、DTA研究结果表明,在交联蒙脱石焙烧时,因交联而使八面体层中羟基易于脱除。云母蒙脱石交联物的酸性与柱的性质有关。硅交联物的强酸点减少,弱酸点增多,B酸所占份额增加。铝交联物强酸点增加,弱酸点减少,L酸所占份额增大。裂解活性主要与催化剂强酸中心有关。活性衰减速率似受强L酸影响更多。     

焙烧温度对ZnO粉体结晶及其光学性能的影响

以草酸铵和醋酸锌为原料,采用直接沉淀法制备ZnO粉体,考察了焙烧温度对粉体结晶和光学性能的影响。采用热重分析(TGA-DTA)、X射线衍射、紫外-可见漫反射(UV-Vis)、荧光分光光度计(FS)和扫描电子显微镜(SEM)等方法对样品进行了分析。结果表明,制备的前驱物为C2O4Zn·2H2O,最低焙烧温度400℃,随着焙烧温度的提高,粉体结晶度提高,一次粒径增大;600℃焙烧后有较强紫外发光峰,粉体由200 nm的粒子排列成层叠状;900℃焙烧后有较强可见发光峰,粉体粒子大于500 nm,团聚严重;粉体有较强的紫外吸收,吸收峰有蓝移。     

载钯磷酸锆的制备和催化性能研究

本文制备了载钯磷酸锆，作为由丙酮和氢气一步法合成甲基异丁基甲酮（ＭＩＢＫ）的催化剂．考察了制备时的ｐＨ对催化剂比表面积、酸度、酸强度以及催化性能的影响．     

Preparation and Evaluation of Theophylline Sustained Release Microcapsules Using Coacervation

Preparation of sustained release dosage forms is one of the main objectives in drug formulation. Theophylline that has a narrow therapeutic index, making it a good choice to prepare a sustained release dosage form. Theophylline sustained release microcapsules were prepared by applying the coacervation method. The effect of the type and ratio of polymers, as well as the type of washing solvents, was studied on particle size, drug loading efficiency, and in vitro drug release profile. Results showed that Eudragit RS and RL could be more suitable polymers for preparation of sustained release microcapsules of theophylline when used in ratio of 1:1 and when the washing solvent was hexane.     

Encapsulation and Sustained Release of Curcumin using Superparamagnetic Silica Reservoirs

For controlled release and targeted delivery of curcumin in an aqueous medium a method of encapsulating curcumin and magnetic nanoparticles inside porous silica matrix has been developed. Curcumin and superparamagnetic nanoparticles are loaded inside porous silica in a single process. The graphic shows the TEM image of microtomed sample of Fe₃O₄ particles surrounded by a silica matrix.

     

Influence of Temperature and Time on the Stability of Silver in Silica Sol-Gel Glasses

The darkening of silica sol-gel glasses doped with 0.05 mol% silver was studied. Six sols were prepared from TEOS and silver nitrate. Different additives were used, to influence the chemical and physical states of silver: oxidizing or reducing agents (H₂O₂, As₂O₅), colloid stabilizer (sodium citrate) and network modifiers (Li₂O, CaO). Sols were gelified at 60°C and densified at 600°C. The samples without additives and those prepared with H₂O₂ at room temperature even if they were protected from light. With increased temperature, the darkening became samples were heated above, 400°C, reversible bleaching took place. This darkening-bleaching is of thermal nature (“thermochromic effect”) and seems to be determined by a reversible aggregation-disaggregation of tiny silver particles. The presence of sodium citrate, as an additive delayed the darkening effect and the presence of CaO delayed it even further. Lithium oxide inhibited it totally.     

肝素化丝素支架作为骨形态发生蛋白-2缓释载体的研究

骨形态发生蛋白-2(BMP-2)的缓释载体一直是骨组织工程中的研究热点.本研究通过化学改性制备了两种肝素化丝素支架,并浸渍吸附BMP-2,研究了BMP-2在不同丝素支架样品上的吸附能力、体外释放性能及其对人骨肉瘤细胞MG-63碱性磷酸酶活性(ALP)的影响.结果表明,肝素化丝素支架对BMP-2具有较强的吸附能力,并能保持其体外缓慢释放性能;MG-63细胞在肝素化支架上生长状态良好,并具有显著的增殖能力,负载BMP-2后的肝素化支架能显著促进MG-63细胞的分化.因此,肝素化丝素支架是一种较理想的BMP-2缓释载体.     

Influence of Drying and Calcination on Remaining Amount and Immobile Character of Titanium on Titanium‐pillared Montmorillonite

Remove of titanium (Ti) from titanium‐pillared montmorillont (TIPM) is not expected during its application as adsorbent and photocatalyst, etc. But studies on immobilization of Ti on TIPM are seldom reported. In this work, TIPM was synthesized from TiCl₄ and Na⁺‐montmorillont (Na⁺‐MMT). Then the prepared TIPM was heated at different temperatures (100, 240 and 450°C) to yield three TIPM samples (TIPM1, TIPM2, and TIPM3). Inductively coupled plasma optical emission spectrometer (ICP‐OES) was used to determine the effect of heating temperature on the remaining amount of Ti on TIPMs. A two‐step treatment method which is often used in the pretreatment and application of TIPM was developed to investigate the immobile character of Ti on TIPMs. X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FT‐IR), N₂ adsorption/desorption isotherm, thermogravimetric analysis and differential scanning calorimetry (TG‐DSC) were also used to characterize TIPMs before and after the treatment. The results show that with an increase in heating temperature, the amount of Ti species remained on TIPM decreases gradually and Ti immobilization is strengthened on TIPM. For TIPM3, less than 2% Ti is removed from TIPM3 after the treatment required to simulate the practical conditions of TIPM in its application, while those of TIPM1 and TIPM2 are 6.6% and 8.4%, respectively. The reason may be that when TIPM is heated, Ti species intercalated into MMT become chemically bonded with the framework of MMT and partially migrate into the layer structure, which make Ti immobile on TIPM firmly during the treatment process.     

科研转化的综合化学实验:银纳米粒子的制备及其催化反应动力学测量

设计了一个包含胶体化学方法制备金属纳米粒子及其作为异相催化剂催化氧化还原反应的动力学过程等内容的本科生综合化学实验。首先采用晶种生长法合成了不同尺寸的球状和片状银纳米粒子,然后经过离心纯化后作为异相催化剂催化硼氢化钠还原4-硝基苯酚的反应,研究了催化反应动力学过程,分析了催化反应的表观反应速率常数和催化剂的活性。本实验可以锻炼学生制备纳米材料和跟踪反应动力学进程的能力,使学生进一步理解异相催化反应机理、熟悉光谱仪器的应用。     

探究不同银配合物对银镜反应的影响

为探究配体与银形成不同银配合物对银镜反应的影响,以氨水、乙二胺、硫氰化钾和甲胺为配体,通过利用不同银配合物的稳定常数研究不同温度条件下银镜反应的情况,对银镜形成时间和质量做比较。结果表明,在这4种配体中,以乙二胺为配体形成的银配合物稳定常数较高,且碱性较强,室温条件下能快速形成高质量的银镜,利于课堂上开展银镜反应实验演示教学。     

波纹状银纳米线的制备及其SERS性能研究

首先通过传统的多元醇方法合成了表面光滑的银纳米线,然后利用Fe（NO₃）₃作为刻蚀剂在室温条件下对合成的银纳米线进行刻蚀得到了具有波纹状表面的银纳米线. 通过扫描电镜（SEM）分析表明：银纳米线的表面粗糙程度随着刻蚀剂量的增加而增加,但过量的刻蚀剂又会导致纳米线的断裂甚至形成球状颗粒;当刻蚀剂的量为100 μL时,获得了波纹状表面的银纳米线. 对结晶紫（CV）的表面增强拉曼光谱（SERS）结果表明,这种波纹状银纳米线的拉曼信号强度比表面光滑的银纳米线提高了约5倍,其检测限可低至10^-10 mol/L. 此外,这种优势还可以延伸到敏感性检测10^-9 mol/L的对巯基吡啶（4-Mpy）分子,可以作为一种普适、有效的SERS活性基底.