辛伐他汀药物动力学及生物利用度

目的研究辛伐他汀(SV)的药物动力学,评价SV片剂和胶囊剂的生物等效性.方法采用反相高效液相色谱法测定10名志愿受试者单剂量口服40mgSV胶囊供试品与40mg标准参比制剂后血药浓度的变化.结果SV胶囊剂和片剂的AUC分别为(150.79±34.17)与(150.05±26.78)h*ng/ml,tmax分别为(2.35±0.41)与(2.45±0.28)h,cmax分别是(25.63±5.09)与(28.14±8.31)ng/ml.结论以SV胶囊供试品与标准参比制剂AUC、cmax和tmax为指标,经双单侧t检验,两者为生物等效制剂.     

口服胸腺肽微球在大鼠体内的药代动力学和生物利用度

目的 :研究胸腺肽微球在大鼠体内的药动学和生物利用度。方法 :用高效液相色谱测定大鼠血中胸腺肽浓度 ,3P87程序计算参数。结果 :胸腺肽微球的药动学参数分别为 :Cmax=2 8.6 0± 9.43μg/ml,tmax=2 10min ,t1/ 2 (β) =144 .40± 19.78min ,AUC0～∞ =76 6 2 .0 3± 70 4.36 μg·min/ml,相对于胶囊剂内容物的生物利用度是 2 38.8%。结论 :大鼠对胸腺肽微球的吸收明显优于胶囊剂内容物。     

RP-HPLC法测定壳聚糖微球中5-氟尿嘧啶的包封率

目的建立壳聚糖微球中5氟尿嘧啶包封率的测定方法。方法采用C18色谱柱,甲醇水(体积比为10∶90)为流动相,检测波长266 nm。用超声浸泡研磨法测定了药物的包封率,并与国内外常用的2种测定方法进行对比。结果平均回收率为103.64%,RSD为1.60%(n=5),质量浓度在2.0~20.0 mg.L-1内线性关系良好。测得壳聚糖微球的包封率为42.21%。而其他2种方法测定同一批微球的包封率值比实际偏高或偏低,即测定方法存在问题。结论该法简便灵敏,测得值真实、可靠,适用于交联法制备的壳聚糖微球中药物包封率的测定。     

尼莫地平片的相对生物利用度及药物动力学研究

目的　对尼莫地平片相对生物利用度及药物动力学进行研究。方法　采用反相高效液相色谱法 (RP HPLC)测定 10名志愿受试者单剂量口服 12 0mg尼莫地平片供试品与标准参比制剂后 ,尼莫地平血药浓度的变化。用 3p87药动学程序处理实验数据 ,并对实验结果进行配对t检验和双单侧t检验。结果　药时曲线下面积分别为 82 .5 1± 2 8.73ng·ml-1·h与 82 .92± 30 .93ng·ml-1·h ,达峰时间分别为 1.75± 0 .2 6h与 1.70± 0 .2 6h ,峰浓度分别为 2 8.84± 9.0 5ng·ml-1与 2 9.0 5± 8.6 9ng·ml-1。结果表明二者AUC、峰浓度及达峰时间无显著性差异 ,尼莫地平片供试品的相对生物利用度为 10 0 .70 %± 7.4 4 %。结论　尼莫地平片供试品与标准参比制剂为生物等效制剂。     

缬沙坦胶囊在人体的药物动力学及相对生物利用度

目的 :了解国产缬沙坦胶囊在人体的药物动力学和相对生物利用度。方法 :采用随机交叉试验设计 ,2 0名男性健康志愿者单剂量口服试验品与参比品各 80mg ,用HPLC法测定血药浓度。结果 :试验品与参比品主要药物动力学参数为T1/ 2α:(1 86± 0 93)h与 (1 94± 0 80 )h ,T1/ 2 β:(9 93± 3 41)h与 (9 81± 4 18)h ,tmax:(2 33± 0 80 )h与 (2 2 8± 0 47)h ;cmax:(2 6 1±1 15 ) μg·mL-1与 (2 43± 1 0 4) μg·mL-1,AUC0→T:(17 2 5± 6 90 ) μg·h·mL-1与 (16 92± 6 34 ) μg·h·mL-1。经交叉试验方差分析 ,上述药物动力学参数无统计学差异 (P >0 0 5 )。试验品的相对生物利用度为 (10 2 2 7± 14 2 6 ) %。结论 :试验品与参比品的cmax与AUC0→t经双单侧t检验分析 ,结果表明两者具有生物等效性。     

阿昔洛韦片相对生物利用度及药物动力学

目的 :研究阿昔洛韦片的药物动力学及相对生物利用度。方法 :采用反相高效液相色谱法测定10名志愿受试者单剂量口服600mg 阿昔洛韦片供试品与标准参比制剂后 ,阿昔洛韦血药浓度变化情况 ,经3p87药动学程序处理。结果 :药 -时曲线下面积分别为 (5 31±0 75) μg/ (ml·h)与 (5 44±0 99) μg/ (ml·h) ,达峰时间分别为 (1 90±0 39)h与 (1 95±0 37)h ,峰浓度分别为(1 12±0 19) μg/ml与 (1 15±0 16) μg/ml。配对t检验与双单侧t检验结果表明 ,二者药 -时曲线下面积、峰浓度及达峰时间均无显著性差异 (P>0 05)。阿昔洛韦片供试品的相对生物利用度为 (98 62±10 09) %。结论 :阿昔洛韦片供试品与标准参比制剂为生物等效制剂。     

磁性壳聚糖微球制备及生物相容性的研究

目的:制备5-氟尿嘧啶磁性壳聚糖微球并评价空载磁性壳聚糖微球的生物相容性。方法:采用乳化交联法制备5-氟尿嘧啶磁性壳聚糖微球并优化制备工艺,采用扫描电镜和振动样品磁强计(VSM)对微球进行表征;四噻唑蓝法观察细胞增殖情况,评估磁性壳聚糖微球的体外细胞毒性;溶血实验和血常规检查评估磁性壳聚糖微球的血液相容性;植埋实验评估磁性壳聚糖微球的组织相容性。结果:经过优化后的5-氟尿嘧啶磁性壳聚糖微球包封率和载药量分别为70.2%和12.3%,Z-均粒径为1 479.6 nm,饱和磁化度为4.79 emu.g-1,微球形态良好、均匀圆整;自制空载磁性壳聚糖微球体外细胞相容性符合要求,显示出良好的血液相容性和体内组织相容性。结论:优化了5-氟尿嘧啶磁性壳聚糖微球的制备工艺,制备的空载磁性壳聚糖微球具有很好的生物相容性。     

没食子酸在大鼠体内的药物动力学及生物利用度

目的建立大鼠血浆中没食子酸的高效液相测定方法;研究大鼠灌胃与静脉给药后没食子酸的药物动力学过程及生物利用度。方法分别灌胃和静脉给予大鼠没食子酸,不同时间点采血,样品经甲醇沉淀蛋白后,采用Phenomenex C18(250 mm×4.6 mm,4μm)色谱柱,甲醇-体积分数为0.5%的冰醋酸水溶液(体积比为7∶93)为流动相,流速为1.0 mL.min-1,检测波长为272 nm,以对乙酰氨基酚为内标测定血浆中没食子酸的浓度。应用DAS 2.0软件计算药物动力学参数。结果大鼠灌胃给药后t1/2α为46.57 min,t1/2β为56.54 min,tmax为66.00 min,ρmax为3.96 mg.L-1,AUC0~t为396.5 mg.min.L-1;静脉给药后t1/2α为9.90 min,t1/2β为78.88 min,AUC0~t为461.9 mg.min.L-1。结论大鼠灌胃和静脉给予没食子酸后,其药-时过程均符合二室模型,绝对生物利用度为42.9%。     

尼莫地平漂浮缓释片的人体药物动力学及相对生物利用度

目的:比较尼莫地平(Nim)漂浮缓释片与普通片的药物动力学、相对生物利用度及体内外相关性.方法:10例男性健康受试者自身交叉对照、单剂量po Nim漂浮缓释片或普通片各120mg,采用HPLC法测定血浆Nim浓度,单室模型拟合药物动力学参数.结果:Nim缓释片和普通片的t_(max)分别为(2.83±0.45)和(0.87±0.27)h(P<0.01),C_(max)分别为(32.82±6.36)和(48.71±8.94)ng/ml(P<0.01),AUC分别为(204.81±45.03)和(159.98±39.96)h·ng/ml(P<0.01).数据经对数转换后进行双单侧检验,两种制剂生物不等效;缓释片的相对生物利用度为(129.89±17.02)%;其体内吸收与体外释药具有显著的相关性(P<0.01).结论:Nim漂浮缓释片生物利用度优于普通片,达到剂型设计要求.     

pH值调节法制备壳聚糖空白微球

目的：介绍一种壳聚糖空白微球的制备方法。方法：将溶有氨水的异丙醇加入到壳聚糖乳液中，使得壳聚糖液滴由酸性变为碱性，壳聚糖凝固析出。结果：制得了粒径在3～8μm左右，粒径分布均匀的壳聚糖微球。结论：使用改变pH值的方法来制备壳聚糖微球，避免了传统固化剂的使用及其缺点。     

The promise of chitosan microspheres in drug delivery systems

Chitosan is a partially deacetylated polymer obtained from the alkaline deacetylation of chitin, which is a glucose-based, unbranched polysaccharide that occurs widely in nature as the principal component of exoskeletons of crustaceans and insects, as well as of the cell walls of some bacteria and fungi. Chitosan exhibits a variety of physicochemical and biological properties resulting in numerous applications in fields such as waste water treatment, agriculture, fabric and textiles, cosmetics, nutritional enhancement and food processing. In addition to its lack of toxicity and allergenicity, its biocompatibility, biodegradability and bioactivity make it a very attractive substance for diverse applications as a biomaterial in the pharmaceutical and medical fields. This review takes a closer look at the biomedical applications of chitosan microspheres. Based on recent research and existing products, some new and potential future approaches in this fascinating area are discussed.     

磁性壳聚糖微球的释药和靶向研究

目的：利用改变pH值法制备磁性壳聚糖微球,并对微球的载药量、缓释特性和磁靶向特性进行测试.方法：采用紫外光谱吸收法测定载药量,渗透袋扩散技术测试微球的释药速度,体外模拟法测定微球的磁靶向性.结果：载药量为37%,包封率62%.微球10h内药物释放约为75%,连续释放78h.外加磁场应在2000～3000Gs左右,施加时间在2h为宜.结论：使用改变pH值法制备的壳聚糖微球,具有较高的载药量和包封率,微球缓释效果明显,并实验测出了适合微球靶向控制的磁场施加方式.     

壳聚糖微球的纤毛毒性和黏附力的考察

目的:考察鼻黏膜用壳聚糖微球的纤毛毒性及黏附力.方法:采用在体蟾蜍上腭纤毛试验法,通过测定纤毛摆动持续时间评价微球制剂的鼻纤毛毒性,测定纤毛输送速率评价微球的黏膜黏附力.结果:壳聚糖微球能显著地降低鼻纤毛毒性,并且具有良好的生物黏附性.结论:壳聚糖是理想的鼻腔给药系统的载体材料.     

Ca-alginate microspheres encapsulated in chitosan beads

Chitosan beads (CBs) incorporating Ca-alginate microspheres (CAMs), containing a drug, were prepared as an oral sustained delivery system. Stable and monodisperse Ca-alginate microspheres loaded with drug were obtained by a membrane emulsification method. The Ca-alginate microspheres were encapsulated in chitosan beads by the ionotropic gelation method with a polyelectrolyte complex reaction between two oppositely charged polyions. The surface and internal characteristics of the beads were improved by ionic cross-linking in tripolyphosphate (TPP) solution adjusted to pH 5.0. The release experiments were performed using lidocaine·HCl (cationic drug) and sodium salicylate (anionic drug) as model drugs. Initial release of drugs depended on the degree of swelling. Ca-alginate microspheres encapsulated in chitosan beads were superior to both drug-loaded CBs and CAMs beads for sustained release because they had a three-layer composition; a calcium alginate core bounded by an inter-phasic chitosan-alginate membrane, which itself was surrounded by a layer of chitosan-TPP.     

Preparation,in vitro characterization,pharmacokinetic, and pharmacodynamic evaluation of chitosan-based plumbagin microspheres in mice bearing B16F1 melanoma

The present study was aimed to evaluate the anti-tumor efficacy and systemic toxicity of chitosan-based plumbagin microspheres in comparison to free plumbagin. The optimized formulation had a mean particle size of 106.35 μm with an encapsulation efficiency of 80.12%. Pharmacokinetic studies showed a 22.2-fold increase in elimination half-life (t_1/2) of plumbagin from chitosan microspheres as compared to free plumbagin. Administration of plumbagin microspheres resulted in a significant tumor growth inhibition and reduced systemic toxicity. These results suggest that chitosan-based microspheres could be a promising strategy for the systemic delivery of anti-cancer agents like plumbagin.     

Preparation oral levofloxacin colon-specific microspheres delivery: in vitro and in vivo studies

The aim of this study was to prepare levofloxacin-loaded chitosan microspheres and to evaluate their in vitro and in vivo characteristics. Glutaraldehyde-crosslinked microspheres were prepared using a spray-drying method, and characterized in terms of the morphological examination, particle size distribution, entrapment efficiency, drug loading and in vitro release. Pharmacokinetics and colon biodistribution studies were used to evaluate that microspheres have more advantage than the conventional formulations. The surface morphology of the freeze-dried microspheres were smooth, discrete with a regular spherical to near-spherical shape. Size of the microspheres after freeze-drying was 4.96?±?0.76?μm and well-distributed. The zeta potential of microspheres was ?29.3?±?2.1?mV. An average drug loading of 9.3?±?0.4% and encapsulation efficiency of 81.1?±?4.7% of levofloxacin microspheres were obtained with the optimized preparation parameters. The cumulative release rate of levofloxacin microspheres was followed by a sustained release and fitted for classic Higuchi kinetic model. In vivo studies showed that chitosan microspheres are thought to have the potential to maintain levofloxacin concentration within target ranges for a long time, decreasing side effects caused by concentration fluctuation, ensuring the efficiency of treatment and improving patient compliance by reducing dosing frequency. It also does not cause any harmful or toxic effect in colon and rectum as evaluated by histopathologic studies.     

苦参碱壳聚糖微球的制备及体外释药

目的:以壳聚糖为囊材制备苦参碱结肠靶向给药微球及评价其体外释药情况。方法:用乳化化学交联法制备微球,以微球的粒径分布百分数、载药量及包封率为优化指标对影响微球制备的主要因素用正交试验设计优化制备条件;并对最佳制备工艺制得的微球进行3种不同递质(人工胃液、人工肠液及大鼠结肠液)中的体外释放度评价。结果:制得的苦参碱壳聚糖微球在电镜下,球形表面圆整,粒径分布适宜,微球平均粒径为(68.3±2.7)μm,平均载药量为(16.0±0.5)%,平均包封率为(66.3±4.2)%。苦参碱壳聚糖微球在人工胃液中2h不释药;在人工肠液中4h内释放不到1%,96h释药不到10%;在含大鼠结肠内容物的磷酸盐缓冲液(pH6.8)中4h释放10%左右,36h释药近50%,此后释药趋于缓慢,96h释药近80%。结论:苦参碱壳聚糖微球几乎不在上消化道释药,而是在结肠靶向释药。     

Encapsulation of vitamin C in tripolyphosphate cross-linked chitosan microspheres by spray drying

This paper describes vitamin C-encapsulated chitosan microspheres cross-linked with tripolyphosphate (TPP) using a new process prepared by spray drying intended for oral delivery of vitamin C. Thus, prepared microspheres were evaluated by loading efficiency, particles size analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), zeta potential and in vitro release studies. The microspheres so prepared had a good sphericity and shape but varied with the volume of cross-linking agent solution added. They were positively charged. The mean particle size ranged from 6.1–9.0?µm. The size, shape, encapsulation efficiency, zeta potential and release rate were influenced by the volume of cross-linking agent. With the increasing amount of cross-linking agent, both the particle size and release rate were increased. Encapsulation efficiency decreased from 45.05–58.30% with the increasing amount of TPP solution from 10–30?ml. FTIR spectroscopy study showed that the vitamin C was found to be stable after encapsulation. XRD studies revealed that vitamin C is dispersed at the molecular level in the TPP-chitosan matrix. Well-defined change in the surface morphology was observed with the varying volume of TPP. The sphericity of chitosan microspheres was lost at higher volume of cross-linking agent. The release of vitamin C from these microspheres was sustained and affected by the volume of cross-linking agent added. The release of vitamin C from TPP-chitosan microspheres followed Fick's law of diffusion.