喷雾干燥法固化黄豆苷元固体脂质纳米粒的研究

目的：建立一种干燥的固体脂质纳米粒的制备方法。方法：采用超声分散法制备黄豆苷元固体脂质纳米粒的混悬液,然后采用喷雾干燥法将其制成干燥的、可再分散的固体脂质纳米粒。结果：在混悬液中黄豆苷元固体脂质纳米粒为球形粒子,平均粒径约为280 nm,喷雾干燥后得到的纳米粒仍为球型,分散后的粒径与喷干前相比有所增大,平均粒径约为720 nm,稳定性较好。结论：喷雾干燥法制备黄豆苷元固体脂质纳米粒是可行的。     

降香挥发油固体脂质纳米粒的制备工艺研究

目的研究降香挥发油固体脂质纳米粒制备中的主要影响因素。方法分别采用高压乳匀法和熔融 超声法制备了降香挥发油固体脂质纳米粒混悬液。以单因素考察和正交设计法研究制备工艺中影响降香挥发油固体脂质纳米粒质量的主要因素 ,筛选出较理想的处方和工艺。结果所得纳米粒为圆整的类球形实体粒子 ,表面光滑 ,平均粒径为 4 0 0nm和 34 5nm ,含药量为 72 11%和71 5 4 % ,包封率为 91 2 7%和 92 36 %。结论采用熔融 超声法制备降香挥发油固体脂质纳米粒实用性更强。     

莪术油固体脂质纳米粒的制备

目的研究影响莪术油固体脂质纳米粒制备的主要因素。方法采用高压均质法制备莪术油固体脂质纳米粒混悬液,以单因素考察和正交设计法筛选出比较理想的处方和工艺,并考察其形态、粒径、载药量及包封率。结果所制得的固体脂质纳米粒为圆整的类球形实体粒子,表面光滑,平均粒径为80.3nm,载药量为11.82%,包封率为81.75%。结论高压均质法可用于莪术油类液体药物固体脂质纳米粒的制备。     

全反式维甲酸固体脂质纳米粒的制备及体内外评价

目的以山嵛酸甘油酯(Compritol 888 ATO)为脂质材料，采用超声分散法制备维甲酸固体脂质纳米粒，并考察其体内外性质。方法选用脂溶性较高的维甲酸作为模型药物，采用超声分散法制备固体脂质纳米粒，并对其各种理化性质进行研究。考察了纳米粒的体外释放，以维甲酸溶液剂为对照，测定了两种纳米粒在大鼠体内的药代动力学参数。结果采用超声分散法可以简便、快速制备得到两种维甲酸固体脂质纳米粒，透射电镜测得纳米粒为圆球状，大小均匀。动态光散射法测得平均粒径分别为(158±9) nm和(89±11) nm。于4 ℃放置1年粒径无明显变化，载药量为3.3%，包封率大于95%。药物体外释放符合Weibull方程。与对照组相比，两种维甲酸固体脂质纳米粒静脉注射后药物在血液中的滞留时间显著延长。结论超声分散法适用于固体脂质纳米粒的制备。     

薄膜分散-超声法工艺参数对烟酸姜黄素酯纳米粒粒径及包封率的影响

摘 要 目的：探索薄膜分散 超声法制备烟酸姜黄素酯固体脂质纳米粒的工艺参数对其粒径及包封率的影响,以期获得制备粒径小、包封率高的工艺参数。方法: 采用HPLC法测定烟酸姜黄素酯的含量,以烟酸姜黄素酯固体脂质纳米粒粒径及包封率为评价指标,通过正交设计试验法、95%可信区间重叠法统计分析,优选薄膜分散 超声法制备烟酸姜黄素酯固体脂质纳米粒粒径小、包封率高的工艺参数。结果:烟酸姜黄素酯固体脂质纳米粒的最佳工艺参数为：水浴温度40℃,茄型瓶旋转速度80 r·min^-1。制得的固体脂质纳米粒平均粒径为107.8 nm,聚合物分散性指数（PDI）为0.583,包封率为68.91%。结论:茄型瓶旋转速度对薄膜分散 超声法制备烟酸姜黄素酯固体脂质纳米粒的粒径影响较大,而水浴温度对其包封率影响较大,两者兼顾考虑,在优选的工艺条件下,可获得平均粒径较小、包封率较高的烟酸姜黄素酯固体脂质纳米粒。     

不同粒径多西他赛固体脂质纳米粒制剂及其细胞毒活性

目的制备不同粒径的多西他赛(docetaxel,DTX)固体脂质纳米粒,考察多西他赛固体脂质纳米粒理化性质,研究粒径对体外释放行为以及细胞毒作用的影响。方法通过热熔超声法制备不同粒径多西他赛固体脂质纳米粒,观察纳米粒形态,测定其包封率、粒径、Zeta电位。考察粒径因素对固体脂质纳米粒体外释放行为、体外细胞毒性的影响。结果制备的纳米粒均为球形及类球形,3种粒径的多西他赛固体脂质纳米粒平均粒径分别为(83.7±8.4)、(162.7±11.9)、(232.1±26.4)nm;Zeta电位分别为-24.19、-23.67、-23.19 mV;包封率分别为98.03%、97.84%、97.92%。60 h粒径分别为83、16、232 nm的多西他赛固体脂质纳米粒在释放介质中分别累计释放86.34%、76.98%、67.14%。3种不同粒径多西他赛固体脂质纳米粒(DTX-SLN-83,DTX-SLN-162,DTX-SLN-232),多西他赛原料药(DTX solutions)以及空白SLN溶液与多西他赛的混合溶液(physi-calm ixture)对MCF-7细胞作用24 h的IC50值分别为3.36、6.20、9.74、13.15、12.92 mg.L-1;48 h的IC50值分别为0.93、2.01、4.35、9.48、9.21 mg.L-1;72 h的IC50值分别为0.30、0.91、1.67、7.36、7.82 mg.L-1。随着多西他赛固体脂质纳米粒粒径的减小,其肿瘤细胞杀伤力逐渐增强。结论热熔超声法可用于制备不同粒径多西他赛固体脂质纳米粒。降低固体脂质纳米粒粒径有利于药物更完全地释放,同时增强其对肿瘤细胞的杀伤能力。     

酮洛芬固体脂质纳米粒的制备

目的：微乳法制备固体脂质纳米粒,以酮洛芬作为模型药物,考查其载药性能。方法：通过对空白微乳粒径和稳定性考查,确定优化处方,将其保温分散于冷水中制备固体脂质纳米粒。对影响其质量的工艺因素和处方因素进行考查和优化设计,筛选最优处方。结果：制备固体脂质纳米粒的直接影响因素包括脂质用量、药物的用量、冷水相温度和微乳保温温度等,所得固体脂质纳米粒的平均粒径（143.9±1.2）nm,多分散系数为0.443。载药固体脂质纳米粒包封率为81.47%,载药量为8.16%。结论：该法稳定可靠,可用于酮洛芬固体脂质纳米粒的制备。     

三氧化二砷纳米粒的制备及对4种肿瘤细胞的抑制作用

目的采用星点设计优化处方,制备三氧化二砷固体脂质纳米粒并探讨其对4种肿瘤细胞的抑制作用。方法采用乳化超声法制备三氧化二砷固体脂质纳米粒。采用MTT法考察三氧化二砷固体脂质纳米粒对4种肿瘤细胞的体外抑制作用。结果筛选的最优处方为PEG-单硬脂酸甘油酯用量0.11 g,大豆卵磷脂的用量0.18 g。平均粒径为131.54 nm,包封率73.46%,载药量为1.07%。不同浓度三氧化二砷固体脂质纳米粒对4种细胞均有抑制增殖作用。结论采用乳化超声法制得的三氧化二砷固体脂质纳米粒具有较好的稳定性,粒子分布均匀,符合制剂学要求。携带阳离子三氧化二砷固体脂质纳米粒组抑制作用最强。     

人参皂苷Rd固体脂质纳米粒的制备

目的:制备人参皂苷Rd固体脂质纳米粒,并考察其理化性质。方法:从旋转薄膜-超声分散法、乳化蒸发-低温固化法、高剪切乳化超声法和高压乳匀法中优选出制备方法;在脂质、表面活性剂等辅料和主药用量的单因素考察基础上,采用正交试验设计,确定最佳处方组成和制备工艺条件;用凝胶柱色谱和HPLC法测定包封率,透射电镜观察形态,激光粒径分析仪测定粒径和Zeta电位。结果:脂质、表面活性剂、助表面活性剂和主药的用量对Rd固体脂质纳米粒的粒径、Zeta电位和包封率均有不同程度的影响。高压乳匀法适合制备Rd固体脂质纳米粒。纳米粒表面呈圆整的球状,大小相近,分散均匀;平均粒径为(102.7±27.0)nm,Zeta电位为(-44.9±9.5)mV,包封率和载药量分别为(81.8±2.6)%和(6.37±0.21)%(n=3)。纳米粒稳定性良好,在4℃下保存4周后,粒径和包封率变化不明显。结论:高压乳匀法适合制备人参皂苷Rd固体脂质纳米粒,工艺稳定可行。     

氟尿苷二醋酸酯固体脂质纳米粒的研制及质量评价

目的：对氟尿苷二醋酸酯固体脂质纳米粒的制备工艺和含量测定方法进行研究，并对其质量进行评价。方法：采用薄膜超声分散法制备氟尿苷二醋酸酯固体脂质纳米粒，并对其包封率、形态等性质进行研究。结果：制得氟尿苷二醋酸酯固体脂质纳米粒形态均匀圆整、粒径范围为（215．3±83．1）nm，包封率为98．27％，裁药量为8．20％。结论：选择薄膜超声分散法制备氟尿苷二醋酸酯固体脂质纳米粒方法可行，为开发氟尿苷新型注射制剂提供了实验依据。     

A NONPARAMETRIC PROCEDURE OF THE SAMPLE SIZE DETERMINATION FOR SURVIVAL RATE TEST

Inthesurvivalstudiesofchronicdiseases,themostfrequentlyusedmethodsofdataanalysisarethenonparametricestimationsandcomparisonsofsurvivalratesatdifferenttimesbuttherehavebeennomatchedmethodsfordeterminingtherequiredsamplesizesofar.Insteadhavebeenoftenusedtheparametricmethodsbasedontheassumptionofexponentialdistributions[1～7]suchthattherelevantsamplesizesmaynotbesatisfiedwiththeprescribedpower.Thispaperreportsanonparametricprocedureofthesamplesizedeterminationforsurvivalratetest.1　SurvivalRateT…     

两生存率检验所需样本容量的模拟

本文以模拟试验展示以前提出的两生存率检验所需样本容量测定方法的行为。取α=0.05(单侧),β=0.1,按不同数值的最小临床承认疗效差量或两生存率和终检率交叉组合得出32种方案结合Weibull生存分布形状参数1/3—3形成160个试验集各重复1000次。在几乎全部指数生存分布试验集,该检验的观测功效符合预定功效。在如此大范围形状参数Weibull分布下,变异甚微。这提示,这种方法对于指数生存分布十分精确,对于不同形态的实际分布,仍然适用。     

Polyurethane-based microparticles: Formulation and influence of processes variables on its characteristics

This study reports the development of polyurethane-based microparticles and the influence of some processes variables on its characteristics. These microparticles were prepared by emulsion polymerization, using poly(caprolactone) diol (PCL) and poly(propylene glycol), tolylene 2,4-diisocyanate terminated (TDI) or poly(propylene oxide)-based tri-isocyanated pre-polymer (TI). The reaction of polymerization was confirmed by attenuated total internal reflection Fourier transformed infrared spectroscopy (ATR-FTIR). Their thermal characteristics were investigated by dynamical mechanical thermal analysis (DMTA) and thermogravimetric analysis (TGA). For good microparticles formation, formulation 80/20 (mass ratio isocyanate/PCL) was the most indicated. Their spherical shape and smooth surface were observed by optical and scanning electron microscopy (SEM). Zeta potential measurements suggest that ionized carbonyl groups existent at the surface can be responsible for the negative potentials obtained. Respecting size and size distribution of the particles, measured by laser diffraction spectroscopy (LDS), the stirring speed and type were the process variables that most influenced it.     

激光散射法测定阿维A原料药粒度

目的：建立测定阿维A原料药的粒度及其分布的方法。方法：采用Malvern Mastersizer2000激光粒度分析仪、Hydro 2000MU湿法进样器,以《中国药典》粒度和粒度分布测定法中的光散射法进行阿维A原料药的粒度分析并进行方法学考察,泵速为1500r/min,遮光比为5%～15%,背景与样品的扫描时间为5s,样品折射率为1.569,样品吸光率为0.01。结果：方法学考察结果d（0.5）的RSD均〈3%,d（0.1）和d（0.9）的RSD均〈5%;4批阿维A原料药的d（0.1）均小于5μm,d（0.5）均小于10μm,d（0.9）均小于20μm,符合《中国药典》相关要求。结论：该方法简便、准确、重复性好,适用于阿维A原料药的粒度控制。     

激光散射法测定乳糖的粒度

目的：确定激光散射法测定乳糖粒度分布，并与传统的筛分法进行比较。方法：Malvem Mastersizer 2000激光粒度分析仪，Scirocco 2000干法进样器；振动进样速度为50％；分散气压，60目和200目为2×10^5Pa，70目、80目、100目为5×10^4Pa；背景及样品的扫描时间为15s；遮光度为0．5％～5％；颗粒折射率为1．347；颗粒吸收率为0．1。Sympatec Helos＆Rodos激光粒度分析仪，振动进样速度为60％；分散气压为5×10^4Pa；透镜为2．5mm，遮光度为4％～10％。OCTAGON DIGITAL高速筛分机；筛分时间2min；振动幅度9。结果：激光散射法可以测定各种规格的乳糖样品，由体积平均粒径D[4，3]可以直观地表征不同规格的乳糖颗粒大小的差异，由d（0．1）、d（0．5）和d（0．9）可以看出其粒度分布特征。基于米氏理论或弗朗霍夫理论进行运算的激光粒度仪均可用于乳糖的粒度分析，两者的测定结果无显著性差异。结论：虽然筛分法与激光散射法均可以表征乳糖的粒度分布，但激光散射法能更好地表征样品的粒度分布，同时可减少测量过程中人为操作误差的影响。     

激光粒度仪测定环索奈德粒度分布的应用研究

目的 建立激光粒度仪测定环索奈德粒度分布的测定方法。方法 采用马尔文2000激光粒度仪，以浓配法配制供试品溶液，表面活性剂浓度为0.01%(W/W)吐温20，分散介质水500mL，遮光度界限为10%~15%，泵转速为2000r/min，超声能量为12.5，超声定时120s，样品测量时间10s，样品测量快照10000，背景测量时间10s，背景测量快照10000。结果 3批样品中环索奈德粒径分布特征值d0.1、d0.5和d0.9平均值分别为1.215、2.726和5.734μm，平均标准差分别为0.086、0.186和0.251μm，测定结果与显微镜法基本一致。结论 本法快速、简便、重现性好、精密度高，适用于微粉化活性成份环索奈德的粒度测定。     

High Resolution Size Determination of 20 nm Colloidal Gold Particles by SedFFF

Purpose. Assessment of lower size limit of Sedimentation Field-Flow Fractionation (SedFFF), specifically to evaluate if the method is suitable to determine the size and size distribution of 20 nm colloidal gold particles with high resolution. Methods. Sedimentation Field-Flow Fractionation was used to determine the size of the colloidal particles. Due to the high density of gold it was possible to extend the lower size limit of SedFFF well below 20 nm. The size distribution of a gold colloid was obtained from the peak broadening caused by the polydispersity of the sample. The peak broadening due to instrumental imperfections was determined. For comparison purpose the particles were also sized using SEM and PCS. Results. The mean diameter of the particles was determined to be (20.87 ± 0.05) nm, the standard deviation in size being 1.04 nm (about 5%). SEM could confirm that the particles are about 20 nm in diameter. A sizing with PCS was not possible. The particles have a strong tendency to aggregate and PCS yields a diameter that is much too large. Conclusions. At optimized analytical parameters Sedimentation Field-Flow Fractionation is an effective method to measure the size of gold particles as small as 15 nm with an accuracy of about 0.1 nm. The polydispersity of the sample can easily be determined.     

Sample Size Re-estimation Designs In Confirmatory Clinical Trials—Current State,Statistical Considerations,and Practical Guidance

A sample size re-estimation (SSR) design is a flexible, adaptive design with the primary purpose of allowing sample size of a study to be reassessed in the mid-course of the study to ensure adequate power. In real world drug product, biologic, and device development, there may be large uncertainty in key factors that drive the sample size estimation for a confirmatory clinical trial. For example, early phase studies may have encouraging results but could be of shorter duration, or use a different endpoint than what is required for confirmatory phase clinical trials. The negative impact of high uncertainty at design stage for a confirmatory trial can be mitigated by an SSR design. Recent surveys have reported an encouraging upward trend in the use of SSR designs in clinical trials since the release of the draft guidance for adaptive design clinical trials for drugs and biologics by the U.S. Food and Drug Administration in 2010 (U.S. Food and Drug Administration (FDA) (February, 2010), Draft Guidance for Industry: Adaptive Design Clinical Trials for Drugs and Biologics). To support broad understanding and acceptance of SSR designs in confirmatory settings, especially unblinded SSR designs, we summarize statistical methods pertaining to SSR designs, including recent development in this field, and discuss design alternatives among blinded SSR, unblinded SSR, and conventional group sequential designs. To support appropriate implementation of SSR designs, we make recommendations on operational logistics for trial conduct based on accumulated experience in recent years, and provide points to consider for final data analysis and reporting for studies where the sample size has been increased following either a blinded or an unblinded SSR algorithm.     

Statistical Analysis for Two-Stage Seamless Design with Different Study Endpoints

In the pharmaceutical industry, it is desirable to apply an adaptive seamless trial design to combine two separate clinical studies that are normally conducted for achieving separate objectives such as a Phase II study for dose finding and a Phase III confirmatory study for efficacy. As a result, an adaptive seamless Phase II{/}III trial design consisting of two phases, namely a learning phase and a confirmatory phase, is commonly considered in pharmaceutical development. In some cases, however, the study endpoints for the two separate studies may be different due to long treatment duration. In this case, test statistics for the final analysis based on the combined data are necessary developed. In this paper, a test statistic utilizing data collected from both phases is proposed assuming that there is a well established relationship between the two different study endpoints. Formula for sample size calculation based on the proposed test statistic is derived. Sample size allocation at the two phases is also discussed.     

Statistical Monitoring of Clinical Trials: Fundamentals for Investigators,L. A. Moyé

We consider collecting the measurements of a gold standard and two methods with error from each site of subjects. We propose an asymptotic test statistic to compare the concordance rates of two methods with the gold standard and a closed-form sample size formula. Through simulations, we show that the test statistic accurately controls the type I error in small sample sizes, and the sample size formula accurately maintains the power in various settings. The proposed test statistic and the sample size formula can be easily modified for other indices for agreement such as sensitivity and specificity. A real eye study is taken as an example.