Pharmacokinetics and efficiency of brain targeting of ginsenosides Rg1 and Rb1 given as Nao-Qing microemulsion

Nao-Qing solution has been shown to be clinically effective in the treatment of acute ischemic stroke (AIS). The purpose of this study was to improve the pharmacokinetics and brain uptake of Nao-Qing, administered as an oil-in-water microemulsion. Sprague–Dawley (SD) rats were given Nao-Qing microemulsion by intranasal or intragastric routes. Samples of blood, brain, heart, liver, lung and kidney were collected at pre-determined time intervals, and the contents of ginsenosides Rg1 and Rb1 (active ingredients of the Nao-Qing microemulsion) were analyzed by high-performance liquid chromatography (HPLC). The results showed that contents of ginsenosides Rg1 and Rb1 in Nao-Qing microemulsion was 8475.13?±?54.61?μg/ml and 6633.42?±?527.27?μg/ml, respectively, and that the particle size, pH and viscosity of the microemulsion were 19.9?±?5.07?nm, 6.1 and 3.056?×?10^?3?Pas, respectively. Absorption of ginsenoside Rg1 was higher than that of ginsenoside Rb1, which was barely detectable after intragastric administration; furthermore, the concentration of ginsenoside Rg1 in blood and other tissues at each time point was lower for intragastric than for intranasal administration. Compared with intragastric administration, intranasal administration resulted in a shorter t_max (0.08 versus 1?h), a higher C_max (16.65 versus 11.29?μg/ml), and a higher area under the concentration–time curve (AUC) (592.91 versus 101.70?μg?h/ml) in the brain. The relative rates of uptake (R_e) and the ratio of peak concentration (C_e) in the brain were 126.31% and 147.48% for ginsenoside Rg1, respectively. These data illustrate that intranasal administration can promote the absorption of drugs in Nao-Qing microemulsion and achieve fast effect.     

Self-assembly synthesis of ZnO with adjustable morphologies and their photocatalytic performance

ZnO with hierarchical microspheres and hexagonal prisms structures were successfully synthesized by hydrothermal microemulsion route. Based on X-ray diffraction and scanning electron microscopy observation of the products at the different reaction time periods, the formation mechanism of three-dimensional hierarchical ZnO microspheres was proposed. Ultraviolet and visible diffuse reflectance spectra indicated that as-synthesized ZnO microspheres had enhanced absorption in both ultraviolet and visible light areas. The photocatalytic activities of as-synthesized products were evaluated by monitoring the degradation of methylene blue solution. Due to the synergistic effects of the high crystallization and special hierarchical structure, the hierarchical ZnO microsphere exhibited the highest photocatalytic activity.     

微乳常温水基超声波机用清洗剂的研制

奥氏体不锈钢板,经拉深工艺,成筒体型的产品后,要求对筒体表面的拉深油,用超声波机清洗,现采用的清洗剂是强碱与表面活性剂两种产品配伍使用,要求温度为(60±5)℃,清洗时间为5 min,在60℃高温消耗能源的同时,清洗剂所产生的蒸汽,既有强碱的刺激味道,还有随时能够对人体构成伤害的不足之处。经检测,净洗力在89.7%。没有达到JB/4323—1999(水基金属清洗剂)标准要求,为克服上述不足之处,研制了一种微乳常温水基超声波机用清洗剂。     

O/W型微乳液应用于三线态湮灭上转换介质研究

光子上转换是吸收低能量（长波长）的光发射高能量（短波长）光的过程,在太阳能光伏、光催化等领域具有潜在应用价值而受到广泛研究,然而通常介质采用有机溶剂及绝氧处理都大大限制了上转换的实际应用.本文报道了可用于三线态湮灭上转换过程的新介质-O/W型微乳液,该体系制备简单、无毒环保,无需除氧脱气条件下,上转化发光稳定,具有未来实际应用的潜力.     

苯乙烯—丙烯酸酯类乳液在涂料中的应用与发展

本文在揭示苯丙乳液的组成、以及该组成与其性质之间关系的基础上 ,提出苯丙乳液的微粒化是实现其高功能化的重要途径。对研究中可能出现的问题提出了解决的办法 ,并进行了论证。     

Wettability reversal of reservoir rock surface through surfactant stabilized microemulsion

In the process of the tertiary recovery of oil and gas resources, it is necessary to use external fluids to displace the crude oil in the reservoir. Whether the crude oil on the surface of the rock can be effectively displaced and the wettability of the rock can be changed to avoid re-adsorption by the crude oil is directly related to the level of oil recovery. Therefore, it is critical to study the cleaning and wettability reversal of reservoir rock surface. Because microemulsions have outstanding performance in changing the wettability of rocks and solubilizing crude oil, this paper uses cetyl trimethyl ammonium bromide (CTAB) as a surfactant and n-butanol as a co-surfactant to prepare microemulsions. The performance of microemulsions with different microstructures on the cleaning and wettability changes of crude oil on the rock surface were studied. The results show that the water-in-oil (W/O) microemulsion has good cleaning efficiency, and the oil removal rate on the sandstone core surface can reach 79.65%. In terms of changing the wettability of the rock surface, W/O, bi-continuous phase (B.C.) and oil-in-water (O/W) microemulsions can change the core surface from lipophilic to hydrophilic. And the effects of the B.C. and O/W microemulsions are more obvious. The microemulsion system that was prepared based on cationic surfactants has a good application prospect in changing the wettability of the reservoir and cleaning the adsorbed crude oil.     

内标法研究Winsor Ⅲ型微乳液的醇分布及其增溶参数

利用气相色谱内标法,测量了不同微乳体系形成WinsorⅢ型微乳液时,正丁醇在油相和水相的体积分布,根据测量结果,对增溶参数的计算进行了修正。研究发现,对于单一阴离子或阴/阳离子复配表面活性剂微乳体系,形成WinsorⅢ微乳时的平衡油相中只含有正辛烷和正丁醇,未检测到水,平衡水相中只含有水和正丁醇,未检测到正辛烷;正丁醇在平衡油相中的体积分数较大,均在11%—12%之间变化,正丁醇在水相中的体积分数较小,在单一表面活性剂微乳体系中维持在1%—2%,而在复配表面活性剂微乳体系中则在2%—4%。修正后的最佳增溶参数SP**较原来增加,最大增幅达15%,最佳盐度S**有所减小,最大减幅为5%,且在最佳盐度条件下对应的界面膜中,随着正丁醇和表面活性剂的摩尔比nA/nS增加,微乳液的增溶能力也随之增强。     

烷基糖苷在高效氯氰菊酯微乳剂中的应用研究

选用新一代绿色表面活性剂烷基糖苷(APG)为乳化剂,研制高效氯氰菊酯微乳剂,对溶剂、表面活性剂的用量进行了对比与筛选,通过制剂质量技术指标的测定,确定了5%高效氯氰菊酯微乳剂的最佳配方。对最佳配方进行了重复性试验,表明该剂型具有良好的热、冷贮稳定性,各项理化指标均符合微乳剂产品标准要求。     

交联聚丙烯酰胺纳米微球的制备及性能评价

以丙烯酰胺(AM)单体水溶液为分散相,Span80/Tween80为乳化剂,煤油为分散介质,绘制了AM/H2OSpan80/Tween80-煤油体系的拟三元相图。依据拟三元相图配制了含油相质量分数52.0%、Span80/Tween80(质量比4∶1)复合乳化剂质量分数7.8%、水相质量分数40.2%的W/O微乳液(以体系总质量计),在70℃利用反相微乳液聚合法制备了纳米级交联聚丙烯酰胺微球。结合激光衍射粒度分析仪(LPSA)探讨了交联剂、引发剂用量及搅拌速率等合成条件对交联PAM微球粒径及吸水溶胀性能的影响,并采用透射电子显微镜(TEM)、扫描电子显微镜(SEM)对微球形貌进行了表征,确定具有较高吸水倍率的交联PAM微球的优化合成条件为:交联剂(N,N-亚甲基双丙烯酰胺)MBA用量0.60%、引发剂(过硫酸铵)APS用量0.50%(以单体质量计)、搅拌速率1 000r/min。溶胀实验显示,该条件下合成的微球在1.0×105mg/L矿化度地层水中吸水倍率为1 690,表现出良好的耐盐性,高吸水倍率。SEM和TEM结果显示,微球具有较好的球形度、单分散性好,粒径分布较为均一,约为150~200 nm。岩心封堵实验表明,聚合物微球胶乳对地层有良好的封堵性,具有封堵、突破、深入、再封堵的逐级调剖特性。