GM-1缓释微球的制备及体外释药特性研究

目的:制备GM-1的乳酸/羟基乙酸共聚物(PLGA)微球,考察其一般性质和体外释药特性。方法:应用W/O/W型乳化溶剂干燥法制备GM-1的PLGA微球,测定微球粒径、载药量、包封率和体外释药曲线。结果:微球形态规则,粒径约为(18±8)μm,载药量约为4.9%,包封率约为61%,微球体外释药规律符合Higuichi方程Q=0.153t1/2+0.03705(r=0.9950)。结论:GM-1微球体外释药特性及其制备工艺良好,体外具有明显缓释作用。     

罗哌卡因乳酸羟基乙酸共聚物微球的制备及体外释药研究

目的:优化罗哌卡因乳酸羟基乙酸共聚物微球制备工艺,并考察其粉粒学特征和体外释药特性。方法:以乳酸羟基乙酸共聚物为载体,采用W/O/W乳剂-扩散溶剂挥发法制备微球,以微球的粒径、药物包封率、载药量及微球形态等重要粉粒学特征为考察指标,通过正交分析试验优化微球制备工艺,并进行体外释药研究。结果:以优化处方制备的制剂,外观光滑圆整,平均粒径为(2.525±0.047)μm,粒径在1.8～5.0μm的占总数的80%以上,载药量(6.067±0.312)%,包封率(58.05±1.169)%。其体外释药曲线可用Higuchi方程拟合,192h累积释药率达82%,t1/2=60.16h。结论:罗哌卡因乳酸羟基乙酸共聚物微球具有明显的缓释性。     

利培酮长效注射微球的制备及体外释放的研究

目的：制备利培酮长效注射微球并考察其体外释放行为。方法：使用乳酸-羟基乙酸共聚物（PLGA）为材料,采用乳化-溶剂挥发法制备利培酮微球,观察微球的形态及粒径,测定微球的载药量和包封率,考察微球的体外释放情况。结果：利培酮微球表面圆整,粒径集中在40～80μm之间。微球的包封率较高,达到80％以上,以低分子量PLGA（50：50）制备的微球,体外突释很高达到40％以上;以高分子量PLGA（75：25）制备的微球,在高载药量时突释较小,可持续释放达3周以上。结论：以高分子量PLGA制备的高载药量的利培酮微球,体外突释较小可缓释达3周以上。     

牛血清白蛋白阳离子微球的制备及体外评价

目的 制备牛血清白蛋白(BSA)口服阳离子微球,考察天然阳离子物质壳聚糖(CHS)的加入对蛋白微球的粒径、电动电势、包封率、载药量及体外释放情况的影响。方法 以乳酸/羟基乙酸共聚物(PLGA)和壳聚糖(CHS)为载体材料,采用W/O/W复乳-溶剂挥发法制备牛血清白蛋白乳酸/羟基乙酸共聚物-壳聚糖(PLGA/CHS)阳离子微球。通过正交设计优化制备工艺,确定最佳处方。建立准确而简便的蛋白含量测定方法,并对微球进行体外评价。结果 最佳处方为：BSA浓度为150 g·L^-1、PLGA浓度为8%、外水相体积为80 mL、壳聚糖浓度为0.2%。制得的微球形态圆整,平均粒径为(6.9±5.5)μm,为表面荷正电的阳离子微球[ζ电势=(10.0±0.6)mV],包封率为(75.4±4.6)%,载药量为(9.3±0.2)%。体外释放结果表明,在模拟胃液和模拟肠液中,壳聚糖的加入均能减少突释,延缓药物的释放。结论 与PLGA微球相比,制得的PLGA/CHS阳离子微球表面带正电,具有较高的包封率和载药量,可以延缓药物释放,同时减少突释现象。     

牛血清白蛋白阳离子微球的制备及体外评价

目的制备牛血清白蛋白（BSA）口服阳离子微球,考察天然阳离子物质壳聚糖（CHS）的加入对蛋白微球的粒径、电动电势、包封率、载药量及体外释放情况的影响。方法以乳酸／羟基乙酸共聚物（PLGA）和壳聚糖（CHS）为载体材料,采用W／O／W复乳-溶剂挥发法制备牛血清白蛋白乳酸／羟基乙酸共聚物-壳聚糖（PLGA／CHS）阳离子微球。通过正交设计优化制备工艺,确定最佳处方。建立准确而简便的蛋白含量测定方法,并对微球进行体外评价。结果最佳处方为：BSA浓度为150g·L^-1、PLGA浓度为8％、外水相体积为80mL、壳聚糖浓度为0．2％。制得的微球形态圆整,平均粒径为（6．9±5．5）μm,为表面荷正电的阳离子微球[ζ电势=00．0±0．6）mV],包封率为（75．4±4．6）％,载药量为（9．3±0．2）％。体外释放结果表明,在模拟胃液和模拟肠液中,壳聚糖的加入均能减少突释,延缓药物的释放。结论与PLGA微球相比,制得的PLGA／CHS阳离子微球表面带正电,具有较高的包封率和载药量,可以延缓药物释放,同时减少突释现象。     

罗哌卡因-醋酸地塞米松PLGA微球的制备及体外释药特性研究

目的 制备罗哌卡因 醋酸地塞米松聚乳酸羟基乙酸共聚物（PLGA）微球（简称微球）并研究其体外释药特性。方法以PLGA为载体,采用W1/O/W2双重乳化 溶剂挥发法制备微球,研究实验过程中有机相PLGA浓度、外水相/有机相体积比、内水相体积、外水相聚乙烯醇（PVA）浓度几项因素变化对罗哌卡因 醋酸地塞米松PLGA微球粒径、表面形态﹑载药量﹑包封率和突释行为的影响。结果有机相PLGA浓度在制备微球的过程中是一个关键性因素。随着PLGA浓度增加,微球粒径增大,载药量﹑包封率明显提高,突释降低;外水相/有机相体积比增大,微球粒径增大, 载药量﹑包封率明显提高,微球表面更加光滑﹑微孔减少,突释降低;随着内水相体积增加使得微球表面的微孔明显增多,突释增加,载药量﹑包封率降低;当外水相PVA浓度由0.5%增加到2%,微球粒径变小,突释效应增加。通过优化条件制备的微球形状为球形,外观光滑圆整,粒径分布均匀,其中＞90%分布在20～70 μm。罗哌卡因载药量（7.48±0.33）%,包封率（70.97±2.36）%;醋酸地塞米松载药量（1.52±0.16）%,包封率（57.30±1.17）%。结论采用W1/O/W2双重乳化 溶剂挥发法成功制备罗哌卡因加醋酸地塞米松PLGA微球;以优化工艺制备的微球,在体外具有明显的缓释行为,释药曲线呈典型S形三阶段模式。     

扑尔敏PLGA缓释微球的制备及体外质量评价

目的以扑尔敏为模型药物,开发一种PLGA缓释微球给药系统。方法采用复乳-溶剂挥发法制备扑尔敏PLGA缓释微球,紫外分光光度法测定其载药量、药物释放。结果制得的扑尔敏PLGA缓释微球平均粒径为(112±57)μm,含药量为(798.33±145.00)μg,载药量为(0.32±0.12)%;药物9 d累积药物释放量可达87%。结论本研究扑尔敏PLGA缓释微球制备方法简单,药物能达到长期缓慢释放。     

GM-l PLGA微球的制备及其体外释药性质研究

目的制备GM l PLGA微球，考察其一般性质和体外释药特性。方法应用W/O/W乳化溶剂干燥法制备GM l PLGA微球，测定微球粒径、载药量、包封率和体外释药曲线。结果微球形态规则，粒径约为（18±8） μm，载药量约为4.9%，包封率约为61%，微球体外释药规律符合Higuichi方程：Q=0.153t1/2+0.037 05(r=0.995)。结论GM l PLGA微球的制备工艺良好，体外释药呈明显的缓释作用。     

紫杉醇PLGA微球制备及体外性质评估

目的：以乳酸-羟基乙酸共聚物（PLGA）为材料,制备用于肿瘤内注射的紫杉醇PLGA长效缓释微球.方法：采用改良溶剂蒸发法制备,对微球的体外性质以及不同剂量（10,15,25 kGy）60Coγ射线对微球性质的影响进行考察.结果：制得的微球形态圆整,载药量、包封率、平均粒径和跨距分别为1.53%,97.29%,42.72μm和0.95.药物体外释放30 d累计释放达到56.19%,体外降解30 d后微球失去完整结构,表面粗糙.3个剂量60Coγ射线的灭菌效果均良好,且对微球的体外性质均无明显影响.微球中二氯甲烷的残留量低于药典规定的限度.结论：紫舷杉醇PLGA微球满足缓释长效的要求,对恶性肿瘤的间质化疗具有一定前景.     

替硝唑聚乳酸微球的制备及其体外释药性能

目的：采用聚乳酸[poly（DL-lactide）]制备替硝唑微球。方法：考察分散递质明胶溶液的浓度、油相中聚乳酸的浓度、投药比和搅拌速度等因素的影响，应用正交实验优选最佳制备工艺条件。结果：替硝唑聚乳酸微球的最佳制备工艺稳定、重复性好，微球表面圆整，粒径分布均匀，微球平均粒径为30．2μm，平均载药量为6．7％，平均包封率为64．5％。该微球在14d的药物累积释放率达81．2％。结论：替硝唑聚乳酸微球缓释时间长达14d，用于牙周炎的治疗是有效的。     

Biodegradable poly(D,L-lactide-co-glycolide) (PLGA) microspheres for sustained release of risperidone: Zero-order release formulation

The preparation and investigation of sustained-release risperidone-encapsulated microspheres using erodible poly(D, L-lactide-co-glycolide) (PLGA) of lower molecular weight were performed and compared to that of commercial Risperdal Consta^? for the treatment of schizophrenia. The research included screening and optimizing of suitable commercial polymers of lower molecular weight PLGA50/50 or the blends of these PLGA polymers to prepare microspheres with zero-order release kinetics properties. Solvent evaporation method was applied here while studies of the risperidone loaded microsphere were carried out on its drug encapsulation capacity, morphology, particle size, as well as in vitro release profiles. Results showed that microspheres prepared using 50504A PLGA or blends of 5050-type PLGAs exerted spherical and smooth morphology, with a higher encapsulation efficiency and nearly zero-order release kinetics. These optimized microspheres showed great potential for a better depot preparation than the marketed Risperdal Consta^?, which could further improve the patient compliance.     

2-脱氧葡萄糖聚乳酸微球的制备及其体外释药性能的研究

目的采用W/O/O乳化溶剂挥发法制备2-脱氧葡萄糖聚乳酸微球(2-Deoxyglucoseloadedpoly(DL-lactide)microspheres,2DG-PLA-MS),并研究其体外释药性能。方法考察3个因素(即投药比、水丙酮体积比和丙酮液体石蜡体积比)对微球的粒径、载药量和包封率的影响,应用正交实验优选最佳制备工艺条件。结果2DG-PLA-MS的制备工艺稳定,重复性好,微球表面圆整,粒径分布均匀,微球平均粒径45μm,平均载药量为42.41%,平均包封率为72.63%。该微球在14d的药物累积释放率达82.96%。结论2DG-PLA-MS具有明显的缓慢释放作用,能够实现延长药物作用时间、减少给药次数、降低药用剂量和减少不良反应等作用。     

醋酸戈舍瑞林缓释微球的制备及体外释药研究

目的制备醋酸戈舍瑞林缓释微球,考察其一般性质和体外释药特性。方法采用复乳-液中干燥法制备醋酸戈舍瑞林微球,测定微球的外观形态、粒度分布和体外释药曲线。结果微球形态规则,粒径约为85.6μm,微球体外释药规律符合Higuchi方程：Q=16.202t1/2＋1.550 3,r=0.991 0。结论制备的醋酸戈舍瑞林微球具有长时间的缓释作用。     

5-Fluorouracil-loaded microspheres prepared by spray-drying poly(D,L-lactide) and poly(lactide-co-glycolide) polymers: Characterization and drug release

5-Fluorouracil (5-FU), a hydrosoluble anti-neoplastic drug, was encapsulated in microspheres of poly(D,L-lactide) (PLA) and poly(lactide-co-glycolide) (PLGA) polymers using the spray-drying technique, in order to obtain small size microspheres with a significant drug entrapment efficiency. Drug-loaded microspheres included between 47?±?11 and 67?±?12?µg 5-FU?mg^?1 microspheres and the percentage of entrapment efficiency was between 52?±?12 and 74?±?13. Microspheres were of small size (average diameter: 0.9?±?0.4–1.4?±?0.8?µm microspheres without drug; 1.1?±?0.5–1.7?±?0.9?µm 5-FU-loaded microspheres) and their surface was smooth and slightly porous, some hollows or deformations were observed in microspheres prepared from polymers with larger T_g. A fractionation process of the raw polymer during the formation of microspheres was observed as an increase of the average molecular weight and also of T_g of the polymer of the microspheres. The presence of 5-FU did not modify the T_g values of the microspheres. Significant interactions between the drug and each one of the polymers did not take place and total release of the included drug was observed in all cases. The time needed for the total drug release (28–129?h) was in the order PLA?>?PLGA 75/25?>?PLGA 50/50. A burst effect (17–20%) was observed during the first hour and then a period of constant release rate (3.52?±?0.82–1.46?±?0.26?µg 5-FU?h^?1 per milligram of microspheres) up to 8 or 13?h, depending on the polymer, was obtained.     

Reduction in burst release after coating poly(D,L-lactide-co-glycolide) (PLGA) microparticles with a drug-free PLGA layer

The high initial burst release of a highly water-soluble drug from poly (D,L-lactide-co-glycolide) (PLGA) microparticles prepared by the multiple emulsion (w/o/w) solvent extraction/evaporation method was reduced by coating with an additional polymeric PLGA layer. Coating with high encapsulation efficiency was performed by dispersing the core microparticles in peanut oil and subsequently in an organic polymer solution, followed by emulsification in the aqueous solution. Hardening of an additional polymeric layer occurred by oil/solvent extraction. Peanut oil was used to cover the surface of core microparticles and, therefore, reduced or prevented the rapid erosion of core microparticles surface. A low initial burst was obtained, accompanied by high encapsulation efficiency and continuous sustained release over several weeks. Reduction in burst release after coating was independent of the amount of oil. Either freshly prepared (wet) or dried (dry) core microparticles were used. A significant initial burst was reduced when ethyl acetate was used as a solvent instead of methylene chloride for polymer coating. Multiparticle encapsulation within the polymeric layer increased as the size of the core microparticles decreased (< 50 µm), resulting in lowest the initial burst. The initial burst could be controlled well by the coating level, which could be varied by varying the amount of polymer solution, used for coating.     

替莫唑胺壳聚糖缓释微球的制备及体外释药特性

目的:制备替莫唑胺壳聚糖缓释微球,并对其体外释药模式进行研究.方法:以替莫唑胺为模型药物,采用乳化交联法制备壳聚糖微球,两步优化法优化处方和制备工艺.通过测定微球的粒径及其分布、载药量、包封率和体外释放速度对微球进行质量评价.结果:优化工艺制得的微球平均粒径为(3.9±1.6)μm,载药量为(7.1±0.5)%(n=3),包封率为(25.0±0.8)%(n=3),体外释药特性研究具有良好的缓释特性,在0～8 h符合Higuchi方程,Q=11.717 26.951t1/2(r=0.980),8～24 h符合一级释放曲线,lnQ=4.37 0.007 5t(r=0.983).结论:通过优化处方和制备工艺,采用乳化交联法可制备出以壳聚糖为载体、替莫唑胺为模型药物的缓释微球,其体外释药具有明显的缓释作用.     

胸腺肽明胶微球的制备和体外释药的特性

目的:为提高胸腺肽的生物利用度,增强疗效,制备胸腺肽的明胶微球.方法:用乳化交联法制备胸腺肽明胶微球,正交设计法筛选其最佳制备工艺,Lowry法测定药物的含量,计算微球的载药量、包封率及体外释药量.结果:微球粒径范围为1.0～30.2 μm,平均粒径为14.64 μm,平均载药量为20.20%(w/w),平均包封率为80.82%,其体外释药符合Higuchi方程,稳定性考察实验结果表明其稳定性较好.结论:本法制备的胸腺肽明胶微球粒径分布集中,粒径大小符合设计要求,体外释药有明显的缓释作用,具有良好应用前景.     

重组降血压肽缓释微球的制备与体外释放

目的采用复乳溶剂蒸发法制备重组降血压肽(rAHP)缓释微球。方法以聚乳酸(PLA)为缓释材料,利用正交设计优化微球制备的最佳工艺条件,并考察了微球的体外释药特性。结果微球制备的最优工艺为:油相中PLA的浓度为7.5%、初乳搅拌速度为900 r/min、内水相与油相体积比为1∶10,外水相聚乙烯醇124浓度为5%;按此工艺制备的微球粒径跨度小、分布均匀,包封率为81.35%,载药量在10.92%,微球得率在80.26%,微球的平均粒径分布范围在75～80μm之间;载药微球在磷酸盐缓冲液中0.5 h内的累积释药量为17.5%,第15天累积释药率达到98.6%。结论该微球制备工艺成熟,包封率高,符合我国药典对缓释制剂的指导原则要求。     

不同封端的PLGA/PLA-醋酸曲普瑞林微球的制备及体内外评价

目的考察微球载体材料聚乳酸-羟基乙酸共聚物(poly-lactic-co-glycolic acid,PLGA)和聚乳酸(poly(D,L-lactide acid),PLA)的不同封端基团对于包载醋酸曲普瑞林(triptorelin acetate,TA)微球的形态、粒径、包封率、体外释放行为以及体内药效学的影响。方法使用复乳化-溶剂挥发法制备包载TA的PLGA和PLA微球;用扫描电镜观察微球的形态,用激光粒度测定仪测定微球的粒径;建立高效液相色谱法(HPLC)用于TA包封率及体外释放度的测定;采用酶联-免疫吸附法考察了微球经肌肉注射后对正常雄性Sprague Dawley大鼠血浆睾酮浓度的影响。结果制备得到的微球形态为球形或类球形,平均粒径约为30μm。PLGA和PLA,尤其是PLGA,其分子末端基团对TA的包封率和体外释放速率均有影响。酯封端的PLGA微球的包封率显著高于酸封端的微球,而酯封端的释放速度要慢于酸封端。体内药效学实验结果显示,大鼠体内睾酮水平在注射微球后两个小时达到峰值,之后逐渐下降,不同微球之间无显著性差异。结论不同封端结尾的PLGA和PLA对微球形态、包封率和体外释药速率有显著影响,但对正常大鼠体内睾酮水平的影响没有显著性差异。