替硝唑固体分散体的制备及其体外释放特性研究

目的:利用固体分散技术制备替硝唑固体分散体,增加替硝唑溶解度和溶出速度。方法:以聚乙二醇(PEG)为载体材料,采用溶剂-熔融法制成固体分散体,测定表观溶解度,进行体外溶出试验,并采用差示扫描量热(DSC)法鉴别药物在固体分散体中的存在状态。结果:替硝唑的溶出度和表观溶解度随PEG的比例不同而不同,且溶出度随载体用量增加而增加。固体分散体的DSC曲线中替硝唑药物的特征熔融峰消失。结论:所制得的固体分散体能明显提高替硝唑的溶出度和表观溶解度。     

格列喹酮固体分散体的制备及溶出度测定

目的:制备格列喹酮固体分散体并考察其体外溶出性。方法:以聚乙烯吡咯烷酮K30(PVP)、聚乙二醇6000(PEG)为载体,溶剂熔融法和溶剂法制备格列喹酮固体分散体,并与原料药比较体外溶出度。结果:载体比例越大,药物溶出愈快。载体为PVP所制固体分散体的体外溶出行为总体优于载体为PEG者。格列喹酮-PVP固体分散体(1∶7)10min内体外溶出度达到70%以上,优于格列喹酮原料药。结论:成功制备了格列喹酮固体分散体。     

艾地苯醌固体分散体的制备及体外溶出度研究

目的:制备艾地苯醌固体分散体,并考察其体外溶出度。方法:以泊洛沙姆407(P407)为载体,单因素考察不同制备方法(熔融法和溶剂法)和不同药载比(1∶1、1∶3、1∶8)对药物溶出度的影响,并采用差式扫描量热(DSC)、X-射线粉末衍射(XRD)鉴别药物在固体分散体中的存在状态。结果:以溶剂法制备的药载比为1∶3的艾地苯醌固体分散体,其体外溶出度约为80%。艾地苯醌在固体分散中主要以无定型或分子状态存在。结论:成功制得体外溶出度较高的艾地苯醌固体分散体。     

淫羊藿素-泊洛沙姆188固体分散体的制备及溶出度研究

目的:制备淫羊藿素-泊洛沙姆188固体分散体以提高淫羊藿素的溶出度。方法:以泊洛沙姆188为载体,采用熔融法制备固体分散体。通过体外溶出度比较,考察了载体泊洛沙姆188的用量(淫羊藿素-泊洛沙姆188质量之比为5∶1、3∶1、2∶1、1∶1、1∶3、1∶5、1∶7、1∶9、1∶11、1∶13、1∶15、1∶17、1∶19、1∶27、1∶31)、熔融温度(60、70、80℃)、冷却温度(-20、0、20℃)对固体分散体中淫羊藿溶出度的影响;同时比较了淫羊藿素原料药及其物理混合物、固体分散体的体外溶出度以证实固体分散体的形成。结果:所制固体分散体的淫羊藿素溶出度在一定程度上随载体比例增加而增加,当淫羊藿素与载体之比为1∶17~1∶27时淫羊藿素在120min时的溶出度均在90%以上;熔融温度、冷却温度经综合分析后分别确定为60、0℃;在溶出30 min时,固体分散体的溶出度是物理混合物的1.5倍。结论:制备的固体分散体显著提高了淫羊藿素的溶出度。     

Formulation Development and Dissolution Rate Enhancement of Efavirenz by Solid Dispersion Systems

The aim of this study was to enhance the dissolution rate of efavirenz using solid dispersion systems (binary and ternary). A comparison between solvent and fusion method was also investigated. Solid dispersions of efavirenz were prepared using polyethylene glycol 8000, polyvinylpyrrolidone K30 alone and combination of both. Tween 80 was incorporated to obtain a ternary solid dispersion system. Dissolution tests were conducted and evaluated on the basis of cumulative percentage drug release and dissolution efficiency. Physicochemical characterizations of the solid dispersions were carried out using differential scanning calorimetric, powder X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. Dissolution was remarkably improved in both systems compared to pure efavirenz (P<0.05). An optimum ratio was identified at a drug:polymer of 1:10. Incorporation of Tween 80 to 1:10 formulations formed using solvent method showed further improvement in the dissolution rate. Physicochemical characterization results suggested that efavirenz existed in the amorphous form in all the solid dispersion systems providing evidence of improvement in dissolution. No statistically significant difference (P>0.05) in dissolution was observed between the two methods. Binary and ternary solid dispersion systems both have showed a significant improvement in the dissolution rate of efavirenz. Formulations with only polyvinylpyrrolidone K30 showed best dissolution profile and 1:10 was identified as an optimum drug-polymer weight ratio.     

Docetaxel-Loaded Solid Lipid Nanoparticles: Preparation,Characterization, In Vitro,and In Vivo Evaluations

The aim of the present study was to prepare, characterize, and evaluate solid lipid nanoparticles (SLNs) containing docetaxel (DTX) to improve the efficacy of this chemotherapeutic agent. SLNs containing DTX (SLN-DTX) were prepared by microemulsion and probe sonication techniques. In vitro cytotoxicity of SLN-DTX compared with Taxotere® (TXT) was evaluated on colorectal (C-26) and malignant melanoma (A-375) cell lines. Cellular uptake experiment was also carried out on C-26 cells. In in vivo tests, tumor inhibitory efficacy and survival were compared with TXT on C-26-implanted BALB/c mice. SLN-DTX particle size was 180 nm and PDI of 0.2 with spherical shape. Encapsulation efficacy was more than 98%. SLN-DTX at concentration of 100 μM caused 100% and 99.9% viability reduction in C-26 and A-375 after 48 and 72 h, respectively. The half maximal inhibitory concentration (IC₅₀) of SLN-DTX on C-26 and A-375 was respectively 0.769 and 28.132 μM after 24 h. DTX cell uptake from SLN-DTX was remarkably higher than TXT. SLN-DTX showed better tumor inhibitory efficacy and survival at a dose of 10 mg/kg versus 10 and 20 mg/kg TXT. In conclusion, the results of the present study showed that the efficacy of SLN-DTX was better than TXT in cell-uptake and in vivo experiments.     

穿心莲内酯固体分散体的制备及体外溶出实验

目的应用固体分散体技术,以提高穿心莲内酯的体外溶出速率。方法采用溶剂法制备了含有不同比例表面活性剂吐温-80的穿心莲内酯-聚乙烯吡咯烷酮（PVPk30）固体分散体,采用正交实验优化固体分散体组成,并进行体外溶出;采用X射线衍射（XRD）与扫描电镜（SEM）分析了固体分散体中药物的分散状态。结果穿心莲内酯从固体分散体中溶出的速率明显增加,增加表明活性剂含量有利于药物的溶出;XRD与SEM结果表明,固体分散体中药物以无定形形式存在于载体中。结论以PVPk30为载体,并加入表面活性剂吐温-80制备穿心莲内酯固体分散体能有效地提高穿心莲内酯的溶出速率。     

姜黄素固体分散体的制备及体外溶出度测定

目的：利用固体分散技术提高难溶性药物姜黄索的体外溶出速率。方法：选择聚乙烯吡咯烷酮和壳聚糖两种载体，分别采用溶剂法和溶剂分散法制备姜黄素固体分散体；通过差热分析对固体分散体进行鉴定，并考察姜黄素及其物理混合物和固体分散体的溶出特性。结果：差热分析图谱表明姜黄素-聚乙烯吡咯烷酮（1：3）固体分散体中药物以非晶型存在，而姜黄素-壳聚糖（1：1）固体分散体中，药物与载体形成低共熔物，药物以微晶形式存在于载体中；体外溶出结果表明两种载体制备的固体分散体均能显著提高药物在溶出介质中的溶出速率。结论：以聚乙烯吡咯烷酮和壳聚糖为载体制备姜黄素固体分散体均能有效地提高姜黄素的溶出速率。     

缬沙坦固体分散体的制备及体外溶出度研究

目的采用冷冻干燥法制备缬沙坦（Valsartan）速释固体分散体（SD）来提高其体外溶出度。方法分别以羟丙甲基纤维素（HPMC）、聚乙二醇6000（PEG6000）、聚乙烯吡咯烷酮k30（PVPk30）为载体,十二烷基硫酸钠（SDS）为表面活性剂来制备不同比例的缬沙坦固体分散体,通过测定体外溶出度,来选择最优辅料及比例,结果当以PEG6000载体,SDS为表面活性剂时,且药物：PEG6000：SDS=1：5：1％时药物呈现了很好的水溶性。结论在5min时即可溶出90％以上,很大程度上提高了缬沙坦的体外溶出度。     

熔融法制备非诺贝特固体分散体及体外溶出研究

目的：制备非诺贝特固体分散体。方法：采用熔融法制备,考察药物和载体的比例、混合温度、冷却温度对溶出率的影响,比较固体分散体和物理混合物的溶出率的区别。结果：药物和载体比例达到1∶2时,载体的量足够使药物分散均匀;混合温度对溶出率影响较大;冷却温度对溶出率影响不大。与物理混合物相比,固体分散体将非诺贝特的溶出率显著提高。结论：非诺贝特固体分散体提高了非诺贝特的体外溶出率。     

维A酸固体分散体的制备及其胶囊的溶出度评价

目的:制备维A酸固体分散体,并对其胶囊进行体外溶出度评价。方法:选用聚维酮k30等为辅料,采取溶剂法制备维A酸固体分散体。以体外累积溶出率为指标,在9种不同组成处方中筛选出较佳处方,并进行验证试验。结果:以处方8为较佳处方,所制胶囊体外累积溶出率在45min时均达到95%以上。结论:以聚维酮k30等为辅料可制备溶出度理想的维A酸胶囊。     

Preparation, Characterization, and In Vitro Evaluation of Ezetimibe Binary Solid Dispersions with Poloxamer 407 and PVP K30

Ezetimibe (EZE), a water insoluble drug, depicts variable bioavailability. The objective of the present investigation was to improve dissolution characteristics of EZE, which might offer improved bioavailability. The solid dispersions were prepared using poloxamer 407 (L 127) and polyvinyl pyrrolidone by melt and solvent method, respectively. Phase solubility studies indicated linear relationship between drug solubility and carrier concentration. In vitro release studies revealed improvement in the dissolution characteristics of EZE in solid dispersions. Solid dispersion with L 127 gave better rate and extent of dissolution. The best fit model indicating the probable mechanism of drug release from solid dispersions was found to be Korsemeyer–Peppas. The results of characterization of solid dispersions by Fourier transform infrared spectroscopy, differential scanning calorimetry, and powder X-ray diffraction revealed reduction in drug crystallinity which might be responsible for improved dissolution properties. The tablets of solid dispersion, containing L 127 prepared by direct compression, exhibited better drug release as compared to marketed formulation.     

DRV Liposomal Bupivacaine: Preparation,Characterization, and In Vivo Evaluation in Mice

Purpose. To evaluate the dehydration-rehydration technique to prepare a formulation of liposomal bupivacaine, and to assess its analgesic efficacy. Methods. Bupivacaine hydrochloride (BUP) was encapsulated into dehydration-rehydration vesicles (DRV) of varying phospholipid (PL) compositions. Two bilayer-forming phospholipids were used, the fluid dimyristoyl-phosphatidylcholine and the solid dis- tearoyl-phosphatidylcholine (DSPC), with 20 or 40 mol% cholesterol, in the presence of bupivacaine at a 1.28 or 0.64 BUP/PL mole ratio. After rehydration, drug/lipid ratios were determined. The formulation with the highest drug/lipid ratio (DSPC/cholesterol in an 8:2 mole ratio prepared in the presence of bupivacaine in a 1.28 BUP/PL mole ratio) was adjusted to a final bupivacaine concentration of 3.5% or 0.5%. The duration of skin analgesia after subcutaneous injection in mice produced by these formulations was compared with the conventional administration of a plain 0.5% solution of BUP. In addition, the concentration of residual bupivacaine at the injection site was followed for 96 h. Results. The relatively low organic solvent/aqueous phase and membrane/aqueous phase partition coefficients, together with liposomal trapped volume and BUP/PL mole ratio, indicated that most of the drug was encapsulated in the intraliposome aqueous phase of the DRV. The DSPC/cholesterol 8:2 mole ratio had the best drug encapsulation (BUP/PL = 0.36). Compared to plain BUP, these BUP-DRV produced significant prolongation of analgesia, which is explained by longer residence time of the drug at the site of injection. Conclusions. Bupivacaine-DRV may have a role in achieving safe, effective, and prolonged analgesia in humans.     

Preparation of Alendronate Liposomes for Enhanced Stability and Bioactivity: In Vitro and In Vivo Characterization

Liposomes containing bisphosphonates have been shown to deplete circulating monocytes and reduce experimental restenosis. However, acceptable shelf life was not achieved, and the disruption extent and rate of the vesicles in the circulation has not been examined. Designing an optimal liposomal formulation in general, and for an anti-inflammatory effect in particular, requires careful consideration of the factors that contribute to their in vitro stability and integrity in the blood after injection. An improved liposomal alendronate formulation was prepared by a modified thin lipid film hydration technique followed by extrusion, resulting in relatively smaller size vesicles, narrow size distribution, and low drug to lipid ratio in comparison to the reverse phase evaporation method. In order to rule out premature leakage of the drug, the integrity of the vesicles was examined by means of size-exclusion chromatography in vitro and in vivo, with subsequent analysis of size, drug (fractions of encapsulated and free) and lipid concentrations. Vesicles were found to be stable in serum, with 15 +/- 3% leakage of the drug after 10 min in rabbit's circulation, and intact liposomes were detected in the circulation 24 h following administration. It is concluded that the new formulation results in increased stability (2.5 years) as determined by the insignificant changes in vesicle size, drug leakage, lipid and drug stability, in vitro bioactivity (macrophages inhibition), as well as in vivo in depleting circulating monocytes and inhibition of restenosis in rabbits. Our in vitro stability results regarding dilution in serum paralleled in vivo data. Thus, in vitro assessment may provide a valuable tool in assessing in vivo integrity of liposomal formulations.     

尼莫地平固体分散体的制备及其理化性质表征

目的 考察不同载体材料经双螺杆热熔挤出技术制备尼莫地平固体分散体的工艺参数、理化性质、增溶效果以及物理稳定性。方法 以共聚维酮和3个规格（L、M和H）的醋酸羟丙甲纤维素琥珀酸酯作为载体材料,使用双螺杆热熔挤出机制备尼莫地平固体分散体。使用偏光显微镜、差示热扫描量热分析和粉末衍射考察制得固体分散体的理化性质,使用原位光纤技术测定固体分散体的动力溶解度,并考察固体分散体的物理稳定性。结果 以共聚维酮为载体材料更容易进行热熔挤出操作,挤出过程螺杆扭矩值<30%,口模内熔体压力<15 bar;制得的固体分散体易于粉碎;过饱和度达到6 000 μg·mL^-1,且溶解迅速;同时在2个月加速条件下保持稳定。结论 共聚维酮更适合用做热熔挤出制备尼莫地平固体分散体的载体材料。     

依托度酸固体分散体的制备及体外溶出试验

目的运用固体分散技术制备依托度酸固体分散体并提高其体外溶出速率。方法选用聚乙二醇为载体,采用溶剂-熔融法制备依托度酸固体分散体,通过差热分析对固体分散体进行鉴定。结果差热分析图谱表明,药物以无定形状态分散于载体中。结论依托度酸固体分散体能显著提高依托度酸的溶出速率。     

环孢素A固体分散体的制备及体外溶出

以聚乙二醇1000维生素E琥珀酸酯、聚乙二醇脂肪酸甘油酯的混合物为载体，微粉硅胶为吸附材料，制备环孢素A的固体分散体。溶出试验表明，所得固体分散体的体外溶出用零级方程拟合效果较好。自制胶囊与市售软胶囊在水、0．1mol／L盐酸和pH6．8磷酸盐缓冲液中的体外溶出行为相似。     

沙棘总黄酮-聚乙烯吡咯烷酮K30固体分散体的制备、表征及体外溶出研究

目的:制备沙棘总黄酮(TFH)-聚乙烯吡咯烷酮K30(PVP K30)固体分散体,并对其进行表征及体外溶出研究。方法:采用溶剂法制备不同药载比(1∶1、1∶2、1∶3、1∶4、1∶5)的TFH-PVP K30固体分散体,以溶出参数Td为指标设计单因素试验筛选药载比,以体外溶出度为指标设计正交试验优选制备工艺中的超声时间、水浴温度和干燥时间,并进行验证。采用扫描电镜法(SEM)、差示扫描量热法(DSC)和傅里叶红外光谱法(FT-IR)对固体分散体进行表征。结果:药载比为1∶3时TFH-PVP K30固体分散体的Td最小;最优工艺为超声时间10 min、水浴温度60℃、干燥时间12 h。以此工艺制备的TFH-PVP K30固体分散体90 min的累积溶出度平均值为90.22%(RSD=1.74%,n=3)。SEM、DSC与FT-IR结果表明,TFH以无定形分散在PVP K30载体中,二者之间形成氢键。结论:成功制得TFH-PVP K30固体分散体,其体外溶出度明显提高。