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Tao Li Ya-Jun Shu Jia-Yin Cheng Run-Cheng Liang Shao-Na Dian Xiao-Xun Lv 《Drug development and industrial pharmacy》2015,41(2):224-231
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 tmax (0.08 versus 1?h), a higher Cmax (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 (Re) and the ratio of peak concentration (Ce) 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. 相似文献
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Hong Du Qianjin Feng Xuezhi Yang Rongting Xu Haiyan Li Xiaoying Dong 《Drug development and industrial pharmacy》2014,40(10):1330-1339
Context: The difference between the chemical polarities of the two categories of active chemical constituents in Chinese angelica volatile oil (CAVO) and Chinese angelica water extract (CAWE) greatly limit the development and clinical application of Chinese angelica preparation.Object: The aim of this study is to design and prepare a “whole Chinese angelica” microemulsion (WCAM) that contains both CAVO and CAWE and at the same time to evaluate it in vivo and in vitro.Materials and methods: CAVO and CAWE extracted from Chinese angelica were used as the oil and aqueous phases, respectively, to prepare the WCAM; its physicochemical property was observed, and its drug potency and oral bioavailability were evaluated.Results: The formula of the WCAM was optimized as Tween-80:ethanol:CAVO:CAWE?=?3:3:1:40. The droplet size of the WCAM was 72.64?nm and the WCAM was proved to be physicochemically stable when it was kept at 0?°C, 4?°C, 25?°C and 40?°C for 3 months. The WCAM could markedly prolong blood clotting time, decrease whole blood viscosity and whole blood reduced viscosity at different shear rates, and improve hemorheological parameters. The results of the pharmacokinetic evaluation show that the AUC0–7 of the WCAM was 4510.66 and was about 4.41-fold compared to that of danggui concentrated pills (an existing Chinese angelica pharmaceutical preparation).Conclusion: It can be concluded, that the WCAM is a promising Chinese angelica preparation that has great prospects in the treatment of dysmenorrhea and irregular menstruation. 相似文献
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D相乳化法制备油墨清洗剂 总被引:1,自引:0,他引:1
本文主要介绍了用D相乳化法制备一种特效油墨清洗剂,并对清洗剂性能进行了探讨,这种清洗剂主要成分由烷基酚聚氧乙烯醚、环保油溶剂、十二烷基苯磺酸钠以及水等组成。清洗剂为中性,主要用于清洗印刷操作工手上所沾油墨。这种清洗剂对人体皮肤无伤害,去油墨效果非常显著,且无毒无污染,价格低廉,制作简单,使用方便。 相似文献
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Pd-Ag bimetallic alloy nanoparticles were synthesized by the reverse microemulsion method,and then deposited on Al2O3 to form the supported catalyst.The nanoparticles of Pd-Ag and Pd-Ag/Al2O3 samples were characterized by UV/Vis,HRTEM,EDX,XRD,and XPS.The test results indicated that Pd-Ag bimetallic alloy nanoparticles with a size of about 2 nm and a face-centered cubic(fcc) structure were formed in the measured area of microemulsion.The growth of nanoparticles was effectively limited within the droplet of micoremulsion.TEM image exhibited that the Pd-Ag alloy nanoparticles were well-dispersed on the Al2O3 support.The catalytic performance of various catalysts for selective hydrogenation of acetylene showed that a higher acetylene conversion and selectivity to ethylene upon acetylene hydrogenation was achieved on a nano-sized Pd-Ag bimetallic catalyst with a Pd/Ag alloy supported molar ratio of 1:1.5. 相似文献
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Zhenhua Li Qiang Li Songmin Shang Liang Li Xiaoming Yang Xianghua Yu Guoping Yan 《应用聚合物科学杂志》2011,119(3):1842-1847
Polystyrene/carbon nanotubes composites were readily prepared by reversed microemulsion polymerization. Compared with the composites prepared by solution mixing, the uniform dispersion of carbon nanotubes in polymer matrix could be obtained more easily and the thermal and electrical properties of the as‐prepared composites were also enhanced. The as‐prepared composites were deposited onto a microelectrode array to fabricate a vapor sensor. The response for different organic vapors was evaluated by monitoring the change in the resistance of the composites upon exposure to various gases. The change in resistance was of the order of about 103 for the composites prepared by reversed microemulsion polymerization. The chemical sensors based on the composites prepared by reversed microemulsion polymerization presented excellent reproducibility and reversibility in response. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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