Formation of Regular Hole Pattern in Polymer Films

Ordered macroporous materials recently have attracted much attention. A method that utilizes the condensation of monodisperse water droplets on a polymer solution is proposed for the preparation of honeycomb microporous films. Our results show that it is a general method that can be used for patterning a wide range of polymers. The presence of water vapor and polymer is necessary for the formation of regular holes in films. The formation of hexagonal packing instead of other kinds of packing takes place because the hexagonal packing has the lowest free energy. The formation mechanisms of regular hole pattern and imperfections in the hexagonal packing are proposed.

Hexagonal hole structures in a PMMA film.     

甲氨碟呤脂质体的几种制备方法比较

目的探讨脂质体的制备方法 ,以便在具体工作中根据不同的目的选择适当的制备方法。方法采用逆相蒸发法、注射法、薄膜法和超声法制备包裹了甲氨喋呤和环胞苷的脂质体。对各种方法的关键步骤进行了讨论。结果被包物质如不稳定 ,采用薄膜法轻轻振摇超过 10h ,包封率可比短时间或震荡激烈提高。被包物质如经过短时间的超声和有机溶剂处理 ,采用逆相蒸发法 ,可获得较高包封率。结论根据被包物质的性质及具体工作不同 ,选择适当的脂质体制备方法 ,会得到较高的包封率和工作效率     

黄芩苷脂质体的制备工艺研究

目的:探讨黄芩苷脂质体的制备工艺.方法:采用逆相蒸发法、乙醚注入法和薄膜超声法制备黄芩苷脂质体,SephadexG-50凝胶柱分离脂质体,UV-法测定包封率,Zetasizer3000粒度测定仪测定其粒径,透射电子显微镜进行形态学观察.结果:逆相蒸发法制备的黄芩苷脂质体平均粒径360nm,包封率56.02%;乙醇注入法平均粒径2600nm,包封率26.14%;薄膜-超声法平均粒径1200nm,包封率53.65%.结论:逆相蒸发法制备的黄芩苷脂质体粒径小,包封率高,条件易掌握,可作为黄芩苷脂质体的常规制备方法.     

天然大豆磷脂制备热敏脂质体的方法及质量评价

目的：研究用天然磷脂替代合成磷脂制备热敏脂质体的方法及其质量评价。方法：以天然大豆磷脂为主要材料，胆固醇为附加剂，参照均匀设计原理选取影响脂质体热敏性的两个因素：磷脂与胆固醇的比例、制备温度和超声顺序(作为一个因素来考虑)，每个因素选取五个水平进行实验。采用逆相蒸发法制备氟脲脱氧核苷热敏脂质体并对其药物释放量、粒径大小及水中稳定性进行测定。结果：42℃时，药物释放量达到了被包封药物量的88．28％。水中放置4个月基本稳定，渗透率4．5％。结论：天然磷脂能替代合成磷脂制备具有良好相变温度的热敏脂质体。     

姜黄素聚乙二醇-聚乳酸嵌段共聚物纳米粒的制备及其质量评价

目的制备姜黄素(Cur)聚乙二醇-聚乳酸嵌段共聚物(mPEG-PLA)纳米粒(Cur-mPEG-PLA-NPs),并考察其理化性质、体外释药特性及抗肿瘤活性。方法采用乳化溶剂挥发法制备Cur-mPEG-PLA-NPs,通过正交设计优化处方工艺。利用透射电子显微镜观察纳米粒形态;激光粒度仪考察其粒径和Zeta电位;超速离心法测定其包封率及载药量;透析法考察其体外释药特性;四甲基偶氮唑盐(MTT)法考察其对人肝癌细胞SMMC-7721的抑制作用。结果根据优化处方工艺制备的Cur-mPEG-PLA-NPs外观呈圆形或类圆形,平均粒径为(129.24±1.45)nm,包封率和载药量分别为(82.15±1.07)%和(4.03±0.11)%;体外释药符合Weibull方程;与原料药Cur比较,Cur-mPEG-PLA-NPs对SMMC-7721细胞具有更强的抑制作用(P<0.05)。结论乳化溶剂挥发法可成功制备Cur-mPEG-PLA-NPs,为Cur新剂型的研究开发提供了实验基础。     

pH梯度法制备抗癌复方硫酸长春新碱脂质体

目的：制备同时包结硫酸长春新碱(VCR)、盐酸米托蒽醌(MTO)的复方脂质体并考察其制剂学性质。方法：采用pH梯度法合并逆相蒸发制备同时包结VCR、MTO的复方脂质体；用Sephadex G-50葡聚糖凝胶柱分离,HPLC同时测定VCR和MTO的包封率；以激光散射粒径分析仪测定复方脂质体的平均粒径及Z-电位；透射电镜观测形态；体外释放实验考察复方脂质体的释药特性。结果：所制备复方脂质体VCR的包封率为95.77%,MTO的包封率达99.53%；平均粒径为72.22 nm,Z-电位为-30.97 mV；外观圆整而均匀；体外释放结果复方脂质体中VCR的T_1/2为6.82 h,对照溶液中VCR的T_1/2为1.70 h,MTO在288 h仅释放了0.05%,对照溶液中MTO在12 h释放完全。结论：采用pH梯度法结合逆相法可制得同时包结VCR和MTO的复方脂质体,且包封率高、粒径小,体外释放证实复方脂质体具有缓释特性。     

丹参素钠-PLGA缓释微球的制备及药剂学性能评价

目的:优选丹参素钠-聚乳酸-羟基乙酸共聚物(PLGA)缓释微球的处方工艺并考察其药剂学性能。方法:采用W/O/O型乳化溶剂挥发法制备丹参素钠-PLGA微球,以载药量、包封率及收率为考察指标,通过单因素试验优选处方工艺,并考察其体外释药性能。采用激光粒度分析仪、扫描电子显微镜和X射线衍射法对该微球进行表征。结果:选取内水相体积300μL,PLGA质量浓度125 g·L~(-1),二氯甲烷-丙酮(3∶7),外油相为液体石蜡200 m L,加入正己烷6 m L,0.25%司盘80为乳化剂,1 400 r·min~(-1)搅拌4 h。丹参素钠-PLGA微球平均载药量(20.71±1.42)%,平均包封率(63.27±1.70)%,平均收率(99.10±0.83)%,体外累积释放率达98%需要120 h。平均粒径(71.72±1.71)μm,表面圆整光滑,内部含有蜂窝状孔洞。部分药物可能以晶体状态分散于载体材料中。结论:W/O/O型乳化溶剂挥发法成功制备了丹参素钠-PLGA微球,优选的处方工艺稳定合理,可为丹参素钠制剂的开发提供参考。     

黄芩素固体脂质纳米粒冻干粉的制备及体外释药性质的研究

目的制备黄芩素固体脂质纳米粒并冻干,考察其理化性质及体外释药特性。方法采用乳化蒸发-低温固化法,以包封率为考察指标,正交试验优化其处方并考察其粒径、形态、电位、多分散系数(PDI)及体外溶出。以外观、色泽、再分散性为考察指标筛选最佳冻干保护剂,利用差示扫描量热(DSC)、X射线衍射(XRD)、傅里叶红外光谱(FT-IR)分析药物在纳米粒中的存在状态。结果黄芩素固体脂质纳米粒外观呈球状体,分布均匀,平均粒径为(82.64±6.78)nm,PDI为0.242±0.013,Zeta电位为(-25.7±0.5)m V,包封率为(81.3±1.2)%,载药量为(7.16±0.14)%(n=3),以5%甘露醇作冻干保护剂效果较好,药物以无定形状态分散在脂质载体中,体外溶出实验表明黄芩素固体脂质纳米粒与原料药相比具有明显的缓释作用。结论乳化蒸发-低温固化法制得的黄芩素固体脂质纳米粒,粒径小,包封率高,稳定性好,工艺简单。     

Effects of Solvent Additive and Micro-Patterned Substrate on the Properties of Thin Films Based on P3HT:PC70BM Blends Deposited by MAPLE

Lately, there is a growing interest in organic photovoltaic (OPV) cells due to the organic materials’ properties and compatibility with various types of substrates. However, their efficiencies are low relative to the silicon ones; therefore, other ways (i.e., electrode micron/nanostructuring, synthesis of new organic materials, use of additives) to improve their performances are still being sought. In this context, we studied the behavior of the common organic bulk heterojunction (P3HT:PC70BM) deposited by matrix-assisted pulsed laser evaporation (MAPLE) with/without 0.3% of 1,8-diiodooctane (DIO) additive on flat and micro-patterned ITO substrates. The obtained results showed that in the MAPLE process, a small quantity of additive can modify the morphology of the organic films and decrease their roughness. Besides the use of the additive, the micro-patterning of the electrode leads to a greater increase in the absorption of the studied photovoltaic structures. The inferred values of the filling factors for the measured cells in ambient conditions range from 19% for the photovoltaic structures with no additive and without substrate patterning to 27% for the counterpart structures with patterning and a small quantity of additive.