维生素M的微乳化研究

制备了维生素M微乳液和胶束;电导率法区分了微乳液的O/W、W/O和B.C.区域;研究了微乳和胶束对维生素M增溶及温度对维生素M稳定性的影响;还研究了微乳液体外缓释效果。结果表明,微乳体系及胶束都对维生素M有增溶作用;维生素M对高温比较敏感,但在O/W型微乳液中较稳定。微乳液粒径和多分散度分别为6.481 nm和0.107。     

水包油型纳米乳的影响因素及稳定性研究

以硬脂酸甘油酯为主要表面活性剂,采用高压均质、超声波等高能乳化法制备水包油型(O/W)纳米乳,研究了油脂、醇类、金属离子、增稠剂及制备方法对O/W型纳米乳粒径大小的影响。结果表明,油脂类中肉豆蔻酸异丙酯和霍霍巴油对O/W型纳米乳粒径为500～520 nm;醇类中甘油对乳液粒径的降低能力最强,为360 nm;盐类中,适合浓度的条件下随着盐类价态的增加,乳液粒径从400 nm降低至340 nm;增稠剂中,随着增稠剂量的增加,乳液粒径增加,从280 nm增加至310 nm。探究出高能乳化制备O/W型纳米乳的关键指标及O/W型纳米乳的不稳定性机制符合奥斯特瓦尔德熟化。     

水包油型纳米乳的影响因素及稳定性研究

以硬脂酸甘油酯为主要表面活性剂,采用高压均质、超声波等高能乳化法制备水包油型(O/W)纳米乳,研究了油脂、醇类、金属离子、增稠剂及制备方法对O/W型纳米乳粒径大小的影响。结果表明,油脂类中肉豆蔻酸异丙酯和霍霍巴油对O/W型纳米乳粒径为500～520 nm;醇类中甘油对乳液粒径的降低能力最强,为360 nm;盐类中,适合浓度的条件下随着盐类价态的增加,乳液粒径从400 nm降低至340 nm;增稠剂中,随着增稠剂量的增加,乳液粒径增加,从280 nm增加至310 nm。探究出高能乳化制备O/W型纳米乳的关键指标及O/W型纳米乳的不稳定性机制符合奥斯特瓦尔德熟化。     

树枝化聚己内酯替莫唑胺微球的制备和表征

利用哑铃型三嵌段聚己内酯(PCL)-聚乙二醇(PEG)-聚己内酯作为壁材,十二烷基硫酸钠为乳化剂,二氯甲烷为有机溶剂,去离子水为水相介质,通过W/O/W型复乳法制备替莫唑胺(Temozolomide,TMZ)载药微球.制得的载药微球粒径分布窄、平均粒径为2.20～ 2.42 μm,载药量可达到9.01％,体外释放实验的缓释时间达到27 d以上.     

纳米氧化铈的制备及其反相微乳液的稳定条件

探讨了用于制备氧化铈纳米粒子的反相微乳体系组成及稳定性,以溴化十六烷基三甲基铵/正丁醇/环己烷/水构成了用于制备纳米氧化铈的W/O微乳液,通过测定体系的电导率的方法确定相点,绘制了溴化十六烷基三甲基铵和正丁醇-环己烷-水反相微乳区拟三元相图.结果表明,表面活性剂与助表面活性剂质量比,即溴化十六烷基三甲基铵与正丁醇的质量比等于1.6时为制备纳米粒子的最佳值,加入硝酸铈会使微乳液的区域减小,随着温度的升高微乳区域略微减小.按实验确定的条件,制备出纳米氧化铈,XRD分析结果表明,纳米氧化铈粒径为19~22 nm.     

井冈霉素载药二氧化硅空心微球的原位制备及缓释性能评价

利用正硅酸乙酯在W/O乳液中的原位水解聚合,成功制备了包埋井冈霉素的二氧化硅载药空心微球. 对所得产品进行了SEM, XRD, FT-IR和粒径分布等分析,结果表明,载药空心微球粒径分布窄,范围在7.5~15 mm,球状形貌良好,具有空心结构,呈无定型态. 热重分析表明载药空心微球的药物负载量约为31.9%(w),缓释溶出实验显示载药空心微球药物释放持续时间约240 min,最终释放量达总载药量的90%以上.     

Tween-60+Span-80/异戊醇/环己烷微乳液法制备纳米Fe3O4

采用W/O型Tween-60 Span-80/异戊醇/环己烷微乳液作为"微反应器"合成纳米磁性Fe3O4粒子。研究结果表明纳米Fe3O4粒子磁化率均随着反应温度、pH、铁离子的浓度比例ω(=[Fe2 ]/[Fe3 ])的增大先增大后减小;最优的制备条件为反应温度30℃、ω=1.2:2、pH=11。最优条件下制备的纳米Fe3O4粒子AFM图片表明所得纳米Fe3O4为均匀分散的球形微粒,平均粒径为70nm。     

微乳液法制备纳米二氧化硅及表征

制备Triton X—10/正辛醇/环己烷/水(或氨水)油包水(W/O)型微乳液,讨论了微乳液相关性质与含水量的关系;以正硅酸乙酯(TEOS)为硅源,在制备的微乳液中受控水解制得纳米SiO2粒子,并用FT—IR、TEM、比表面测定进行表征;结果显示含水量和硅源浓度与粒子尺寸相关,TEM照片显示粒径40~80 nm。     

MAP-乙醇-水三元相图的绘制及其在纳米羟基磷灰石制备中的应用

绘制了单烷基磷酸酯(MAP)-乙醇-水三元体系在30℃的相图,用电导法结合偏光显微镜等测试仪器将相图分为W/O微乳区、O/W微乳区、MAP过量区、微乳液与液晶共存区和液晶单相区。选取相图中W/O微乳区内的一个液相组分点,制备了纳米羟基磷灰石。小角X射线衍射、透射电子显微镜分析结果显示:纳米羟基磷灰石具有规则排列的层状微观结构。     

制备纳米BaSO4的W/O微乳液体系组成及稳定性

以Triton X-100/正己醇/环己烷/水制成W/O微乳反胶团体系，通过测定体系的电导率和观察液晶相的出现确定相点绘制了各体系的拟三元相图，研究了温度、盐浓度和油相组分对W/O微乳液体系稳定性的影响.实验发现助表面活性剂与表面活性剂的配比对微乳液的稳定性有显著影响.随着温度的升高，W/O微乳液稳定区域减小，可通过升高温度对微乳液进行破乳；与以纯环己烷为油相的体系相比，油相中含有少量正己烷的体系具有更优异的性质.所得结果为利用该W/O微乳液体系制备纳米颗粒提供了基础数据.     

Formation of W/O microemulsion based on natural glycolipid biosurfactant, mannosylerythritol lipid-a

Mannosylerythritol lipid-A (MEL-A) is a glycolipid biosurfactant abundantly produced from soybean oil by microorganisms at a yield of up to 100 g/L. In this study, the formation of water-in-oil (W/O) microemulsion based on the single component of MEL-A was confirmed using dynamic light scattering (DLS) and freeze fracture electron microscopy (FF-EM). DLS and FF-EM measurements revealed that the diameter of the microemulsion increases with an increase in water-to-surfactant mole ratio (W(0)) ranging from 20 to 60 nm, and the maximum W(0) value was found to be 20, which is as high as that of soybean lecithin. Glycolipid biosurfactant has a great potential for the formation of W/O microemulsion without using any cosurfactants.     

烷基葡糖苷微乳液中苯乙烯聚合的研究

在烷基聚葡糖苷(APG0810)/苯乙烯/水三元体系O/W微乳液中,选用水溶性K2S2O8作为引发剂,制得小粒径(46.6nm)、单分散(P=0.106<0.2)聚苯乙烯颗粒。着重研究了表面活性剂浓度、引发剂浓度以及无机盐浓度对产物粒径和多分散度的影响。最后得出随表面活性剂浓度的增加胶束数目增多,聚合所得颗粒粒径变小(44.3nm),单分散性变差;而随盐浓度的增加聚合物颗粒粒径变小(45.2nm),超过一定浓度时颗粒粒径有增大的趋势;随引发剂浓度的增加聚合物粒径变小(41.2nm)。     

晚香玉香精壳聚糖纳米粒的制备及表征

以三聚磷酸钠(TPP)为交联剂,通过离子凝胶法制备晚香玉香精壳聚糖纳米粒。研究了壳聚糖质量浓度、香精质量浓度、乳化剂与香精的质量比及反应时间对晚香玉香精壳聚糖纳米粒粒径的影响,并采用动态激光光散射仪(DLS)、透射电镜(TEM)、红外光谱仪(IR)及热重分析仪(TGA)对其结构及性能进行了表征。结果表明,当壳聚糖质量浓度为1.71 g/L、香精质量浓度为1.72 g/L、m(乳化剂)∶m(香精)=1∶2、反应时间为1 h时,制备的晚香玉香精壳聚糖纳米粒平均粒径为138 nm,粒径分布系数为0.100,香精装载量达28.4%,能减缓高温下香精的释放速率。     

Nanosize Polyacrylamide/SiO2 Composites by Inverse Microemulsion Polymerization

Nanosize polyacrylamide/silica (PAM/SiO₂) composites were prepared by water- in-oil (W/O) microemulsion process. In this system, aqueous solution of acrylamide containing disperse 10 nm size silicon dioxide was used as the dispersed phase of the microemulsion while the dispersion medium was sodium bis (2-ethylhexyl) sulfosuccinate (AOT)/toluene solution. The size of the synthesized PAM/SiO₂ nanocomposites was 38–76 nm as determined by dynamic light scattering (DLS). The incorporation of nanosize silica filler reduces the particle size of PAM latex. It had also been found that the size of composite particles decreases with increasing filler loading along with better polydispersity. The presence of silica particles in the polymer latex particles and interaction of polymer chains with silica particles in hybrid nanocomposites were characterized by Fourier transform infra red spectrophotometry (FTIR), thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC). The TGA results showed improved thermoresistance and high thermal stability behavior of hybrid composites. The DSC measurements revealed that the incorporation of filler favors crystallization, increases the enthalpy of melting and thermal stabilization of the synthesized composite particles. A scanning electron microscope (SEM) was used to study the morphology and topography of the prepared nanocomposites.     

一氯三嗪-β-环糊精包合晚香玉香精纳米粒的制备及表征

以一氯三嗪-β-环糊精(MCT-β-CD)为壁材,晚香玉香精为芯材,通过包合法制备一氯三嗪-β-环糊精晚香玉香精纳米粒。研究了壁材与芯材的质量比、乙醇与水的体积比、反应时间、反应温度、搅拌速度对晚香玉香精纳米粒粒径的影响,并采用动态激光光散射仪(DLS)、透射电镜(TEM)、红外光谱(IR)及热重分析仪(TGA)对其结构及性能进行了表征。结果表明:在V(乙醇)∶V(水)=1∶0.67,m(香精)∶m(壁材)=1∶15,反应时间10 h,搅拌速度1 300 r/min,温度为35℃的条件下制备的晚香玉香精一氯三嗪-β-环糊精纳米粒的粒径为216.4 nm,粒径分布系数(PDI)为0.221,香精装载量达17.2%,能减缓高温下香精的释放速率。     

反胶束微乳液法制备纳米ZnO

以CTAB/煤油/正辛醇/氨水反胶束微乳体系,采用双微乳液混合法制备了纳米ZnO,考察了CTAB和反应物浓度对ZnO粒径的影响,利用TEM、XRD等手段对产品进行了表征。结果表明,所得纳米ZnO为球形六方晶体,粒径为20~70 nm,且分散性较好。     

十六烷基三甲基溴化铵/正丁醇/正辛烷/水油包水型微乳体系的相行为

文中分别考察了助表面活性剂(正丁醇)、有机溶剂(正辛烷)、温度、钨酸钠溶液浓度对十六烷基三甲基溴化铵(CTAB)/正丁醇/正辛烷/水油包水(W/O)型微乳区域形成的影响,并对该微乳体系的结构进行了电导研究,确定了微乳液体系形成区域及最佳比例配方。研究表明:助表面活性剂、有机溶剂、盐溶液质量浓度对该微乳液体系的微乳区域都会产生影响,温度对该微乳区域几乎没有影响;且当CTAB/正丁醇质量比为1∶2,(CTAB+正丁醇)/正辛烷质量比为4∶6时(滴加蒸馏水前),能够得到较大且稳定的微乳区域。该研究从热力学相图原理上为纳米粒子可控制备提供了理论依据。     

A pH-triggered charge reversal and self-fluorescent micelle as a smart nanocarrier for doxorubicin controlled release

A novel pH-sensitive charge reversal and self-fluorescent polymeric micelle is designed and synthesized successfully. The smart micelle is prepared based on MPEG-polyurethane multi-block copolymer, which is synthesized by polycondensation, with 1, 4-bis (hydroxyethyl) piperazine (HEP) and hydroxyl-sulfamethazine (Hydroxyl-SM) as pH-sensitive molecules and fluorescein isothiocyanate (FITC) as fluorescent segment. The resulting MPEG-polyurethane multi-block copolymer is examined by ¹H–NMR, UV-vis spectra, fluorescence spectra and an acid-base titration. Moreover, the diameter, morphology and cytotoxicity of obtained polymer micelle are measured by dynamic light scattering (DLS), transmission electron microscopy (TEM) and MTT assay. The results indicate that the micelle has a small diameter of less than 200 nm and can remain unchanged within two weeks. Zeta-potential measurement shows that the negative charge of micelle can switch into positive charge as the pH value decreasing from 9.0 to 3.0. Subsequently, the fluorescence intensity decreases significantly with the reducing of pH values. The MTT assay shows the low cytotoxicity and good biocompatibility of the MPEG-polyurethane polymeric micelles. Finally, doxorubicin (DOX) is loaded into micelles to detect in vitro release behavior. The drug loaded micelles show a faster release behavior at pH 5.0 than that at pH 7.4. Therefore, the pH-sensitive charge reversal and self-fluorescent micelle can be a potential smart carrier for delivery and controlled release of protein drug.     

烷基多苷微乳液中苯乙烯聚合的研究

在烷基多苷（APG）／苯乙烯／水三元体系O／W微乳液中,选用水溶性K2S2O8作为引发剂,制得小粒径（35．4nm）、单分散（P=0．180〈0．2）聚苯乙烯颗粒。研究了苯乙烯、过硫酸钾、烷基多苷以及NaCl质量浓度对产物粒径和多分散度的影响。结果表明：聚苯乙烯随苯乙烯的增加颗粒粒径变大（43．8nm）;随过硫酸钾的增加颗粒粒径变大（37．9nm）,多分散度变小（P=0．153）;随烷基多苷的增加颗粒粒径变小（33．4nm）,而多分散度变大（P=0．195）;随NaCl的增加颗粒粒径变大（45．6nm）。微乳结构的转变点对产物有重要的影响。