电导法对CTAB/正丁醇/环己烷/水四组分微乳体系的研究

利用电导率(K)-增溶水量(ml)关系曲线研究了CTAB/正丁醇/环己烷/水四组分微乳体系在不同增溶水量时的3种结构,即油包水(W/O)、油水双连续(B.C.)、水包油(O/W).讨论了表面活性剂CTAB与助表面活性剂正丁醇不同浓度时对微乳液稳定性的影响,得出了微乳液稳定时CTAB和正丁醇的合适配比.     

柠檬烯U型微乳的构建及水增溶过程中微观结构变化过程模拟

以柠檬烯为油相,吐温80为表面活性剂制备微乳,利用拟三元相图研究不同助表面活性剂及其与表面活性剂的不同比值(Km值)对微乳有效区域的影响。结果发现,当油相与表面活性剂之比小于或等于5∶5时,微乳体系可无限增溶,为U型微乳。采用电导率法、黏度法对U型微乳的水增溶过程进行研究,实验结果发现,当含水量小于40%时,微乳体系为油包水(W/O)型;当含水量为40%~60%时,微乳体系为双连续型;当含水量大于60%时,微乳体系为水包油(O/W)型。利用耗散粒子动力学(DPD)方法对水相增溶过程中微乳体系的微观结构和微乳液滴的形态特征变化进行模拟,模拟结果表明,在水相增溶过程中,微乳体系能够在含水量为40%和60%时发生相的转变,与实验结果较好吻合。     

电导法对CTAB／正丁醇／环己烷／水四组分微乳体系的研究

利用电导率（K）-增溶水量（ml）关系曲线研究了CTAB／正丁醇／环己烷／水四组分微乳体系在不同增溶水量时的3种结构，即油包水（W／O）、油水双连续（BC）、水包油（O／W）。讨论了表面活性剂CTAB与助表面活性剂正丁醇不同浓度时对微乳液稳定性的影响，得出了微乳液稳定时CTAB和正丁醇的合适配比。     

番茄红素微乳液制备及降解动力学研究

目的 设计一种包埋手段，最大限度地提高番茄红素的稳定性，延缓番茄红素降解速率，从而扩大番茄红素的应用。方法 以番茄红素晶体为目标芯材，利用伪三元相图获得番茄红素微乳液的最佳配方。利用光降解和热降解动力学模型，探究番茄红素晶体包埋前后的光、热稳定性。结果 制备番茄红素微乳液的最佳配方：油相为乙酸乙酯，表面活性剂为吐温60，助表面活性剂为无水乙醇，表面活性剂与助表面活性剂之比(K_m)为2∶1，此时形成的微乳面积最大为53.05%。番茄红素微乳液中番茄红素的质量浓度为352.90μg/mL，平均粒径为13.22 nm，聚合物分散性指数(PDI)为0.054 8，其构相为O/W型微乳液。制备的番茄红素微乳液具有良好离心稳定性和贮藏稳定性。在不同光照时间和温度处理下，其降解均符合一级降解动力学规律，且微乳中番茄红素降解速率小于番茄红素晶体降解速率。结论 番茄红素被微乳液包埋后提高了水溶性、稳定性，同时能够有效延缓番茄红素晶体的光降解和热降解速率，对番茄红素起到保护作用。     

葡聚糖水凝胶微球的制备与表征

采用反相微乳液交联法,以葡聚糖天然高分子为原料,制备了一系列基于葡聚糖的水凝胶微球。葡聚糖通过高碘酸钠氧化进行醛基化修饰,进一步与乙二胺发生还原胺化反应进行交联;交联反应在以失水山梨酸酯类(Span 80/Tween 80)表面活性剂复配体系作为乳化剂、环己烷为油相构成的油包水型反相微乳液中进行。表面活性剂复配体系的组分配比是影响该葡聚糖水凝胶微球的粒径及形貌的重要因素,研究结果表明,随着表面活性剂复配体系的亲水亲油平衡值(HLB value)增加,微球粒径呈现先减小而后增大并基本保持不变的趋势;当该复配表面活性剂的HLB=5.27(即,m(Tween 80)/m(Span 80)=10)时,获得的葡聚糖凝胶微球粒径最小且平均粒径为(21.6±1.65)μm,粒径分布在15~28μm之间。     

微乳液技术在纳米材料合成中的应用

微乳液是由表面活性剂、助表面活性剂在有机溶剂或水中形成的热力学稳定的各向同性的单分散体系,其分散质点为纳米级。它为纳米粒子的制备提供理想的模板和微环境。本文介绍了纳米材料、微乳液以及运用微乳液技术制备纳米材料以及该法的优点和和应用范围。     

微乳液组分对体系增溶水量的影响及纳米羟基磷灰石的制备

应用电导率法研究了TritonX-100/正戊醇／环己烷体系中各组分及条件对微乳液最大增溶水量的影响。结果表明：当表面活性剂TritonX-100用量为3ml，助表面活性剂选正戊醇用量为1ml，环己烷为油相，温度为48℃，Ca（NO3）2溶液与（NH4）2HPO4溶液分别为0．24和0．14mol／L时，体系增溶水量最大，可得到较高产率的纳米羟基磷灰石。并且用XRD和TEM手段对产物进行了表征。     

NH_3·H_2O皂化二-(2-乙基己基)磷酸微乳液体系的溶水过程研究

研究了NH3·H2 O皂化二 - (2 -乙基己基 )磷酸微乳液体系增溶水过程微观结构的转变 ,测定了增溶水过程电导率和粘度的变化 ,以及在一定溶水量时电导率和温度的关系 ,求得了微乳液颗粒的活化能     

NH3·H2O皂化二—（2—乙基乙基）磷酸微乳液体系的溶水过程研究

研究了NH3*H2O皂化二-(2-乙基己基)磷酸微乳液体系增溶水过程微观结构的转变,测定了增溶水过程电导率和粘度的变化,以及在一定溶水量时电导率和温度的关系,求得了微乳液颗粒的活化能.     

微乳液法制备CNTs/PbO、CNTs/CuO复合材料

采用W/O型微乳液法制备出了CNTs/PbO和CNTs/CuO,利用电导率仪测量体系的溶水量,通过绘制三元相图研究了微乳液组成的表面活性剂和助表面活性剂的配比、温度以及盐的浓度等因素对W/O型微乳液相区的影响。分析得出最佳微乳液体系环己烷和活性剂的比为4 6,表面活性剂和助表面活性剂的比为2 3,反应温度为25℃。根据推进剂的成分,将一定量的燃烧催化剂和黑索今混合,通过热分析表征CNTs/PbO、CNTs/CuO对黑索今的催化热分解。结果表明,新的催化剂明显加快黑索今的热分解,分解峰位降低16.07℃。     

The microstructure characterization of meloxicam microemulsion and its influence on the solubilization capacity

Objective: The aim of this study was to characterize the microstructure of microemulsion consisting of oleic acid, Cremophor RH40, ethanol, and water (K_m?=?2), and investigate the influence of microstructure on the solubilization potential of the microemulsion to meloxicam (MLX).

Methods: Pseudo-ternary phase diagrams of microemulsion were constructed using the H₂O titration method. The microstructures of microemulsion on dilution line N91 were identified by means of conductivity, viscosity, surface tension, and density. The freeze-fracture electron microscopy proved the specific microstructure. Differential scanning calorimetry (DSC) was used to evaluate the position of MLX in microemulsion, and the solubility of MLX in chosen microemulsions on dilution line N91 was measured.

Results: The three microstructures along dilution line N91, including water-in-oil (W/O), bicontinuous (BC), and oil-in-water (O/W) microemulsion, were characterized. The solubilization capacity of W/O microemulsion is the best, compared with the other two, whereas the O/W is the weakest. A possible structure model has been applied for the explanation of difference.

Conclusions: The solubilization capacity of microemulsion is closely related with its microstructure.     

Physicochemical characterization of rutaecarpine-loaded microemulsion system

To develop an o/w microemulsion system containing poorly water-soluble rutaecarpine, the solubility of rutaecarpine in water, ethanol, various oils, and surfactants were investigated. Among the surfactants and oils tested, Tween 20/PEG 400 and castor oil were chosen as the surfactant system and oil phase of the microemulsion, as rutaecarpine was most soluble in them, respectively. Pseudoternary phase diagrams were constructed to obtain the concentration range of oil, surfactant, and cosurfactant for microemulsion formation, and the stability test of rutaecarpine delivered by microemulsion formation was then evaluated. Pseudoternary phase diagrams show that the areas of microemulsion appeared at those with 0-20% Smix (PEG 400/Tween80 = 60/40), 64-81% water, and 10-20% oil. The rutaecarpine (300 µg/g)-loaded microemulsion composed of 10.8% PEG 400, 7.2% Tween 80, 20% caster oil, and 72% water was physically and chemically stable for at least 6 months. Thus, the microemulsion system composed of castor oil, PEG 400, Tween 80, and water could be a stable dosage form for rutaecarpine.     

Physicochemical Characterization of Rutaecarpine-Loaded Microemulsion System

To develop an o/w microemulsion system containing poorly water-soluble rutaecarpine, the solubility of rutaecarpine in water, ethanol, various oils, and surfactants were investigated. Among the surfactants and oils tested, Tween 20/PEG 400 and castor oil were chosen as the surfactant system and oil phase of the microemulsion, as rutaecarpine was most soluble in them, respectively. Pseudoternary phase diagrams were constructed to obtain the concentration range of oil, surfactant, and cosurfactant for microemulsion formation, and the stability test of rutaecarpine delivered by microemulsion formation was then evaluated. Pseudoternary phase diagrams show that the areas of microemulsion appeared at those with 0–20% Smix (PEG 400/Tween80 = 60/40), 64–81% water, and 10–20% oil. The rutaecarpine (300 µg/g)-loaded microemulsion composed of 10.8% PEG 400, 7.2% Tween 80, 20% caster oil, and 72% water was physically and chemically stable for at least 6 months. Thus, the microemulsion system composed of castor oil, PEG 400, Tween 80, and water could be a stable dosage form for rutaecarpine.     

聚乙烯蜡的丙烯酸接枝改性及乳化工艺

以丙烯酸为单体,叔丁基过氧化氢（TBHP）为引发剂,二甲苯为溶剂,对聚乙烯蜡进行接枝改性。结果表明,当m（引发剂）∶m（聚乙烯蜡）=0.5∶100,m（丙烯酸）∶m（聚乙烯蜡）=15∶100,m（二甲苯）∶m（聚乙烯蜡）=300∶100,反应温度为120℃,反应时间6 h的条件下,可制得酸值为14 mg KOH/g蜡的...     

癸酸-棕榈酸-硬脂酸/膨胀石墨蓄能复合相变材料的制备与热性能研究

癸酸、棕榈酸、硬脂酸形成的三元低共熔物与膨胀石墨通过真空浸渍法制备出新型癸酸-棕榈酸-硬脂酸/膨胀石墨储能复合相变材料,适宜的质量比为m(癸酸)∶m(棕榈酸)∶m(硬脂酸)=77.0∶11.5∶11.5,m(癸酸-棕榈酸-硬脂酸)∶m(膨胀石墨)=13∶1。采用DSC、FT-IR、TG、SEM、冷热循环实验和蓄/放热实验研究了材料的结构和热性能。SEM和FT-IR分析结果表明低共熔物与膨胀石墨是通过物理吸附方式结合。DSC结果表明复合材料融化和凝固时的相变温度为28.93℃和16.32℃,相变潜热为137.38J/g和141.51J/g。TG结果表明复合相变材料在100℃以下具有良好的热稳定性。500次热循环和蓄/放热实验表明循环前后复合相变材料的热可靠性好,且使用寿命长。膨胀石墨的添加改善了复合材料的热性能和热导率。研究表明制备的新型复合相变材料具有合适的相变温度、较高的相变潜热和热导率,热性能稳定可靠,可用于低温蓄能领域。     

Solubilization and determination of solution thermodynamic properties of itraconazole in different solvents at different temperatures

The solubility of itraconazole (ITRA) in thirteen pure solvents including water, dimethyl sulphoxide, acetonitrile, methanol, 1,4-butanediol, ethanol, isopropyl alcohol, n-butanol, octanol, ethyl acetate, toluene, benzene, 1,4-dioxane were estimated at the temperatures ranging from 293.15?K to 318.15?K under atmospheric pressure (0.1?MPa). The results reflected that the solubility of ITRA was a function of temperature and was increased with a rise in temperature in each solvent. Moreover, the solubility in polar solvents was less and found to be increased in non-polar solvents. Furthermore, the results of solubilization were correlated by the Van’t Hoff equation, the modified Apelblat equation, the Buchowski???Ksiazaczak λh equation, and the polynomial empirical equation. The polynomial empirical equation proved to be more accurate and suitable for the correlation of solubilities of ITRA in studied solvents at various temperatures. Besides, theoretical ideal solubilities, activity coefficients, and thermodynamic properties of the solution process including standard molar enthalpy, entropy, Gibbs free energy, and excess enthalpy were calculated from the experimental solubility data. These thermodynamic parameters indicated that the solubilization process was not spontaneous, endothermic, and enthalpy driven. Such thermodynamic based solubility data of ITRA will be of immense help in solubilization, synthesis, process development, preformualtion, and dosage form development in pharmaceuticals.     

碳-蒙脱石二维纳米复合粉体制备与提纯

以聚乙烯醇、钙基蒙脱石为原料,通过溶液插层、碳化和气流粉碎工艺和技术制备碳-蒙脱石二维纳米粉体。物相和粒径分析结果表明:在钙基蒙脱石、聚乙烯醇、水的质量比为5∶5∶90的反应体系中,获得层间距d(001)=2.11 nm的聚乙烯醇-蒙脱石插层型复合粉体;400℃碳化该复合粉体获得具有三明治结构特征的碳-蒙脱石复合粉体(d(001)=1.56 nm);将碳-蒙脱石复合粉体气流粉碎可得含碳质量分数为6%左右,平均片径约为2μm,厚度小于30 nm的碳-蒙脱石二维纳米粉体,以管状、单片和多片层堆积等形态存在于体系中。通过梯度离心分离法可以提取不同片径的碳-蒙脱石二维纳米复合粉体。     

Reverse microemulsion region and composition optimization of the AEO9/alcohol/alkane/water system

A reverse microemulsion method was applied to prepare ceramic inks for formation by jet-printing. Different reverse microemulsion systems were studied and optimized in order to obtain high concentration ceramic inks, and an AEO₉/alcohol/alkane/water system was chosen for preparing these ceramic inks as a result of its excellent water-dissolving characteristics. In this paper, different kinds and amounts of alcohol as a co-emulsifier and n-octane as oil, respectively were used to systematically investigate their effects on the microemulsion region in the quasi-ternary phase diagram of the system studied. These were mixed with water to form reverse microemulsion after vigorous stirring. The microemulsion region was determined and the conditions for maximum water-dissolving were given. Additionally, the effect of temperature on the reverse microemulsion region was studied. It was shown that the AEO₉/n-butanol/n-octane/water reverse microemulsion system exhibited excellent behavior in enhancing the amount of water-dissolving and the best composition for maximum water content was AEO₉:n-butanol:n-octane=25.7%:16.8%:57.7% in mass.     

Water/span80/Triton X-100/n-hexyl alcohol/n-octane microemulsion system and the study of its application for preparing nanosized zirconia

For the first time, a brand new microemulsion system (water/span80/Triton X-100/n-hexyl alcohol/n-octane) was studied and applied to prepare nanosized zirconia. In total, three types of aqueous phases (distilled water, 2.0 M ammonia solution, and 0.8 M ZrOCl₂ aqueous solution) have been studied, leading to three different ternary phase diagrams. This work indicates that such microemulsion system has two distinct advantages: on the one hand, significant improvement in the solubilization capability has been obtained (as high as 50 vol.% water content can be achieved in our case in compared with the maximum value around 30 vol.% as in previous reported ones); on the other hand, the cloudy point in our system can be manipulated in a wide range by simply adjusting the content of Triton X-100. Taking these advantages into account, we have successfully prepared nanosized zirconia utilizing this system. Furthermore, the analyses of the recorded DTA, XRD, and TEM spectroscopies have revealed that the calcination conditions are essential for the crystal growth of nanosized zirconia.     

The effect of component of microemulsion for transdermal delivery of nicardipine hydrochloride

Purpose: Nicardipine hydrochloride has been used widely for the treatment of angina pectoris and hypertension. Because of its extensive first pass metabolism after oral administration, the transdermal administration of nicardipine microemulsions was developed in this study. Methods: Microemulsions consisted of isopropyl myristate (IPM), surfactant mixture of Tween 80/Span 80 and/or Tween 80/Span 20, co-surfactant (ethanol) and aqueous phase. Pseudo-ternary phase diagrams were constructed using water titration method. The effect of component of microemulsion on the percutaneous absorption of drug was evaluated by in vitro permeation study. Results: The area of microemulsion isotropic region in the presence of ethanol was comparably larger in the absence of ethanol. The mean droplet size of nicardipine microemulsions ranged from 70 to 123 nm. With addition of ethanol, the droplet size became smaller. The permeation rate and extent of nicardipine microemulsion transport across rat skin was affected by the components of microemulsion. Nicardipine microemulsion had higher flux at surfactant mixture with lower hyrophile-lipophile balance (HLB) value and Tween content. Conclusions: The microemulsion consisted of 52% IPM, 35% surfactant mixture and 13% water had higher permeation rate through rat skin above 122.53±1.87 μg/cm2/h and was expected to develop a transdermal delivery system.