挤出滚圆法制备马来酸曲美布汀胃黏附微球

目的利用适合于工业化生产的方法制备具有较好生物黏附能力和适宜缓释效果的马来酸曲美布汀胃黏附微球。方法通过挤出滚圆法制备马来酸曲美布汀胃黏附微球 ;以动物体内外胃黏膜表面滞留程度 ,考察CP的含量和微球粒径对微球黏附能力的影响 ;以体外释药速率评价热处理 ,CP的含量 ,CP、SA与EC间的比例 ,TM含量 ,微球粒径对微球缓释效果的影响 ;以镇痛效果考察最终处方的药效。结果CP比例增加 ,微球的黏附性增强 ,药物缓释效果降低 ,呈现负相关 ;TM含量增加 ,微球的黏附性降低 ,缓释效果降低 ;微球粒径增大 ,微球的黏附性降低 ,缓释效果增加 ;最佳处方的作用时间延长 ,作用强度增强。结论载药量在 2 0 % (w)以下 ,粒径为 5 0 0～ 90 0 μm,CP含量为 1 3 3 0 % (w)的TM微球在胃黏膜表面具有良好的黏附特性 ,且药物缓释可达 8h。     

盐酸乙胺丁醇微球的制备及体外释药性能

目的 :研究肺靶向性盐酸乙胺丁醇微球的制备和体外释药性能。方法 :采用乳化 热固化法制备微球 ,并对其形态学 ,载药量 ,体外释药等性能进行了研究。结果 :微球粒径在 12～ 42 μm ,载药量为 :(2 1.2 4± 0 .36 ) % (n =5 ) ,体外释药试验结果显示 ,盐酸乙胺丁醇微球体外释药符合Higuichi方程。 结论 :本法制得的盐酸乙胺丁醇微球具有缓释性。     

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.     

小檗碱胃粘附微球的制备和体外性质评价

目的制备小檗碱胃粘附微球并评价其药剂学性质。方法采用液中干燥法制备小檗碱胃粘附微球,以微球的成球效果、载药量、包封率为指标,分别考察无水乙醇与液体石蜡体积比、Span 80浓度、小檗碱用量、乙基纤维素和卡波姆的总用量、乙基纤维素和卡波姆的比例等5个因素,筛选最佳工艺条件,对其制备的微球进行表征,并对所制备的小檗碱胃粘附微球进行体外释放度评价。结果小檗碱胃粘附微球最佳处方为无水乙醇与液体石蜡体积比为1∶8,Span 80浓度为2%,小檗碱用量为800 mg,乙基纤维素和卡波姆的用量分别为500 mg,乙基纤维素和卡波姆的比例为1∶1;制备得到的3批微球的载药量、包封率、粒径、表面形态以及圆整度均符合质量检测要求;制备的小檗碱胃粘附微球具有一定的缓释特性,体外释药行为符合Higuchi方程。结论采用液中干燥法可将小檗碱制备成微球,制备的小檗碱胃粘附微球具有良好的缓释特性。     

盐酸雷尼替丁中空缓释微球的制备及其特性

目的:以盐酸雷尼替丁(RH)为模型药物,研究中空微球的制备,并对制备过程中的影响因素进行考察。方法:以乙基纤维素(EC)为载体材料,乙醇/乙醚为混合溶剂,采用溶剂扩散-挥发法制备盐酸雷尼替丁中空微球。以产率、平均粒径、载药量和微球形态为指标,考察了处方工艺对微球性能的影响。并考察了EC粘度,RH/EC比例以及粒径对微球释药速率的影响。结果:中空微球产率为84.51%,粒径分布均匀,平均粒径632μm,载药量13.71%,包封率55.86%。电镜扫描显示:微球外观圆整光滑,内部为中空结构。体外释药研究表明随着EC粘度的增加释药速率降低;随着RH/EC比例和搅拌速度的增加释药速率增加。最终所得到的中空微球缓释可达24h,体外漂浮实验表明在人工胃液中可持续漂浮48h以上。结论:该处方工艺简便可行,制得的盐酸雷尼替丁中空微球在人工胃液中缓释性和漂浮性良好。中空微球有望成为吸收窗药物的又一新型给药系统。     

吸附和包埋法制备洛美沙星淀粉微球及其体外释放比较研究

目的制备盐酸洛美沙星淀粉微球,并对其体外释药模式进行研究。方法以盐酸洛美沙星为模型药物,采用吸附载药法和包埋载药法制备了载药淀粉微球,通过测定微球载药量、包封率和在不同的释放介质中的体外释放情况,对上述2种方法制备的载药微球进行质量评价。结果吸附法制备的载药微球的平均载药量为14.54μg·mg^-1,药物包封率为39.72%;而包埋载药法制备的淀粉微球的平均载药量为19.32μg·mg^-1,药物包封率为48.95%。体外释药特性研究表明它们具有缓释特性,其中包埋载药法制备的淀粉微球比吸附载药法制备的淀粉微球有更好的缓释能力,在不同的释放介质中释药曲线也有所不同,在模拟胃液中累计释药量只能得到70%;而在模拟肠液中累计释药量能达到80%以上。结论吸附载药法和包埋载药法制备的载药淀粉微球都具有缓释作用,但后者体外释药具有更明显的缓释效果。     

紫杉醇肺靶向微球的制备及体内外评价

目的用生物可降解材料聚乳酸-聚羟基乙酸共聚物(PLGA)制备肺靶向紫杉醇缓释微球。方法在单因素考察的基础上进行正交试验设计,筛选出肺靶向紫杉醇PLGA微球的最佳制备工艺条件;利用桨板法研究了微球的体外释药规律;用小鼠为实验对象,研究了紫杉醇聚乳酸微球的体内组织药物分布。结果制得的微球形态圆整,粒径在5~15μm范围内的占总体积的87.18%,微球平均粒径为9.65μm;包封率为83.8%;载药量为19.7%;体外释药符合Higuchi方程Q=-2.193 7 22.009t0.5,r=0.990 4;体内实验表明紫杉醇微球混悬剂较普通注射剂更趋于聚集在肺组织。结论微球制备工艺稳定,具有明显的缓释作用和肺靶向性。     

载环孢素A海藻酸钙-壳聚糖微球的制备及体外释放特性

目的:针对角膜移植术后免疫抑制治疗需求,制备眼部局部给药的小粒径载环孢素A缓释微球,并进行体外释放考察。方法:以海藻酸钠、壳聚糖为载体材料,采用静电液滴工艺,通过向制备体系添加表面活性剂,制备小粒径载环孢素A微球,设计正交试验优化处方工艺,扫描电镜观察微球表面形态,动态透析法考察微球的体外释放特性。结果:所制微球形态良好,粒径分布窄,平均粒径为(12.4±0.8)μm,包封率为(82.8±1.8)%,载药量为(50.1±1.2)%,体外释放行为用Higuchi方程拟合效果最好。结论:采用静电液滴工艺,通过减小制备体系的表面张力,制备了球形度优良、粒径小、包封率和载药量较高的载环孢素A的壳聚糖-海藻酸盐缓释微球,所得制剂的体外释药规律服从扩散机制。     

碱性成纤维细胞生长因子缓释微球的制备及其性质研究

目的 通过碱性成纤维细胞生长因子(bFGF)缓释微球的制备研究,为bFGF的缓释制剂提供科学依据。方法 以聚乳酸-聚乙二醇共聚物为包裹材料,采用复乳包囊法制备bFGF-聚乳酸-聚乙二醇共聚物缓释微球,并对微球的形态学、粒径分布、载药量、包封率和体外释药等进行研究。结果 所制备的微球表面光滑圆整,球体均匀度好;微球平均粒径为1.543±0.070 μm,平均径距为1.273±0.08;载药量和包封率分别为0.0267％和65.32％;微球的体外释药过程较为稳定,两周释药率为59.98％。结论 bFGF缓释微球比bFGF有明显的缓释作用。     

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。     

盐酸索他洛尔生物粘附微球的制备及体外释药特性研究

目的：制备盐酸索他洛尔生物粘附微球,考察其体外释药特性并评价其粘附性能。方法：应用正交试验筛选盐酸索他洛尔生物粘附微球的最佳处方,采用高效液相色谱法测定盐酸索他洛尔生物粘附微球的含量与释放度,选用滞留率为指标考察微球的粘附特性。结果：盐酸索他洛尔生物粘附微球的最佳处方为盐酸索他洛尔投药量占处方组成的30％．分散相与连续相比为70％,司盘80用量为9．0g;体外释药试验结果表明盐酸索他洛尔生物粘附微球30min累积释药百分率达30％,4h释药达90％;离体法与在体法测得微球胃黏膜上的滞留率分别为（87．6±2．8）％与（60．2±9．8）％。结论：盐酸索他洛尔生物粘附微球处方设计合理,制备工艺简单,与盐酸索他洛尔普通片相比,盐酸索他洛尔生物粘附微球具有一定缓释特性,且其在离体与在体模型中粘附性能良好。     

Spray-dried chitosan/ethylcellulose microspheres for nasal drug delivery: swelling study and evaluation of in vitro drug release properties

The aim of this study was to develop spray-dried chitosan-based microspheres, suitable for nasal delivery of loratadine, and to evaluate their potential of modifying loratadine release. The microspheres were composed with ethylcellulose (EC) and chitosan (CM) in two different weight ratios, 1:2 and 1:3. One-phase systems (dispersions) and two-phase systems (emulsions and suspensions) were subjected to spray-drying, resulting in conventional and composed microspheres, respectively. The microspheres were evaluated with respect to the yield, particle size, encapsulation efficiency, physical state of the drug in the polymer matrix, swelling properties and in vitro drug release profile. It was shown that particle size, swelling ability and loratadine release from spray-dried microspheres were significantly affected by the polymeric composition and feed concentration in spray-drying process. Emulsifying method to produce composed EC/CM microspheres resulted in improved loratadine entrapment and moderate swelling, when compared to conventional chitosan microspheres. It seems like better formation of EC cores and chitosan coating were obtained when higher feed concentration and ultrasonic homogenization were employed in the preparation of emulsion systems and when EC to CM weight ratio was 1:3.     

硝苯地平生物黏附微球的制备及释药机制研究

目的:制备硝苯地平生物黏附微球并考察其体外释药情况。方法:在单因素考察的基础上应用正交设计筛选硝苯地平生物黏附微球的最佳处方,因素为加热温度、聚乙烯醇(PVA)用量、司盘浓度和戊二醛用量,评价指标为累积释药率;考察优化处方所制微球的质量指标如体外黏附力和累积释药率等,研究其释药机制。结果:优化处方工艺为:加热温度60℃、PVA用量0.6 g、司盘浓度5%、戊二醛用量0.6 mL;优化处方所制微球体外黏附力较高,平均载药量约为15%,包封率约为85%,平均粒径约为20μm;微球可持续24 h释药,释药符合Higuchi方程,释药机制符合非Fick扩散机制,即以溶蚀和扩散2种模式释放。结论:硝苯地平生物黏附微球制备工艺简单,具有较好的体外黏附性能和缓释效果。     

苯酰甲硝唑生物粘附微球的制备及粘附性能研究

目的：筛选苯酰甲硝唑生物粘附微球的最佳处方并进行粘附性能评价。方法：应用正交试验设计，以收率和包封产率为指标，选择最佳处方配比；并以滞留率为指标考察制备微球的粘附性能。结果：当苯酰甲硝唑投药量为35％，分散相与连续相比为0．9，乳化剂Span-80用量为7．5g时，苯酰甲硝唑生物粘附微球的收率和包封产率最高；离体法与在体法测得微球胃粘膜上的滞留率分别为（93．4±4．5）％与（58．4±9．3）％。结论：该处方设计合理，制备工艺可靠，质量稳定。     

Preparation, in vitro and in vivo evaluation of algino-pectinate bioadhesive microspheres: An investigation of the effects of polymers using multiple comparison analysis

Ionotropic gelation was used to entrap aceclofenac into algino-pectinate bioadhesive microspheres as a potential drug carrier for the oral delivery of this anti-inflammatory drug. Microspheres were investigated in vitro for possible sustained drug release and their use in vivo as a gastroprotective system for aceclofenac. Polymer concentration and polymer/drug ratio were analyzed for their influence on microsphere properties. The microspheres exhibited good bioadhesive property and showed high drug entrapment efficiency. Drug release profiles exhibited faster release of aceclofenac from alginate microspheres whereas algino-pectinate microspheres showed prolonged release. Dunnet's multiple comparison analysis suggested a significant difference in percent inhibition of paw edema when the optimized formulation was compared to pure drug. It was concluded that the algino-pectinate bioadhesive formulations exhibit promising properties of a sustained release form for aceclofenac and that they provide distinct tissue protection in the stomach.     

长春西汀聚乳酸-聚乙醇酸缓释微球的研制

目的:制备长春西汀聚乳酸-聚乙醇酸(PLGA)缓释微球,并研究其药剂学性质。方法:采用改良O/W乳化-溶剂挥发法制备微球,以PLGA浓度、理论载药量、有机相与分散介质的比例和分散介质中明胶的浓度为4因素,每个因素选定3个水平,按L9(34)的正交设计方案,以载药量、包封率和粒径分布为指标,优化处方。用扫描电镜观察微球的形态,用光学显微镜观察并计算微球的粒径分布,用差示扫描量热(DSC)法研究药物在载体中的分散状态,用紫外分光光度法检测微球中长春西汀含量并计算载药量和包封率,用动态透析释药法进行微球的体外释放研究。结果:最佳处方为PLGA浓度16%,理论载药量20%,有机相与分散介质的比例1:10,分散介质中明胶的浓度1%;制备的长春西汀PLGA缓释微球的形态圆整、光滑,粒径分布均匀,平均粒径为(10.0±0.18)μm(n=500),DSC法分析药物确已被包裹于微球中,载药量为(18.46±0.26)%,包封率为(91.30±0.98)%(n=3),24h累积释药率约为18%。结论:长春西汀PLGA缓释微球制备工艺稳定,质量符合药剂学要求,缓释性好。     

盐酸索他洛尔生物黏附微球的体外释药及黏附性能研究

目的考察盐酸索他洛尔生物黏附微球的体外释药特性并评价其黏附性能。方法采用高效液相色谱法测定释放介质与微球中盐酸索他洛尔含量,并以滞留率为指标考察微球的黏附特性。结果盐酸索他洛尔生物黏附微球30min累积释药百分率达30％,4h释药达90％;离体法与在体法测得微球胃黏膜上的滞留率分别为87．60±2．8％与60．2％±9．8％。结论盐酸索他洛尔高效液相色谱测定方法简便、可靠,与盐酸索他洛尔普通片相比,盐酸索他洛尔生物黏附微球具有一定缓释特性,且其在离体与在体模型中黏附性能良好。     

Floating-bioadhesive microspheres containing acetohydroxamic acid for clearance of Helicobacter pylori

A new strategy based on gastric retention is proposed for the treatment of Helicobacter pylori. (H. pylori) . A synergism between a floating and a bioadhesive system has been explored. Floating microspheres containing the antiurease drug acetohydroxamic acid (AHA) were prepared by a novel quasi-emulsion solvent diffusion method. The microballons were characterized for size distribution, morphology, drug content, drug release, and in vitro floating property. The microballons were coated with 2% w/v solution of polycarbophil by the air suspension coating method. The bioadhesive property of the microspheres was investigated by the detachment force measurement method. In vitro growth inhibition studies were performed in isolated H. pylori culture. The results suggest that AHA-loaded floating microspheres are superior as potent urease inhibitors whereas urease plays an important role in the colonization of H. pylori. We suggest that an oral dosage containing floating-bioadhesive microspheres may form a useful drug delivery system for the treatment of H. pylori.     

Preparation and characterization of ibuprofen microspheres

Ibuprofen was microencapsulated with Eudragit RS using an o/w emulsion solvent evaporation technique. The effects of three formulation variables including the drug:polymer ratio, emulsifier (polyvinyl alcohol) concentration and organic solvent (chloroform) volume on the entrapment efficiency and microspheres size distribution were examined. The drug release rate from prepared microspheres and the release kinetics were also studied. The results demonstrated that microspheres with good range of particle size can be prepared, depending on the formulation components. The drug:polymer ratio had a considerable effect on the entrapment efficiency. However, particle size distribution of microspheres was more dependent on the volume of chloroform and polyvinyl alcohol concentration rather than the drug:polymer ratio. The drug release pattern showed a burst effect for all prepared microspheres due to the presence of uncovered drug crystals on the surface. It was shown that the release profiles of all formulations showed good correlation with the Higuchi model of release.