肺靶向顺铂白蛋白微球的研究

按正交设计筛选了用乳化一化学交联法制备肺靶向顺铂白蛋白微球的最佳制备工艺,并对微球的质量、稳定性、体内分布、动力学特性和安全性进行了系统研究。结果:微球表面圆整,平均粒径为13.13±3.55μm,药物包裹率为21.62%,释药特性符合双相动力学方程;微球在三种条件下贮放了3个月质量稳定;静脉注入小鼠体内,15min分布达高峰,97.52%浓集于肺部,2～3d内基本清除,在肺器官中的动力学特性可用二室开放性模型描述;肺器官病理切片观察,微球对肺组织无病理性损伤。     

甲睾酮聚乳酸微球的制备及其释药性能研究

目的制备甲睾酮聚乳酸微球,研究其体外释药过程。方法采用乳化-溶剂挥发法制备甲睾酮聚乳酸微球;以0.25%SDS-5%乙醇(pH3.4)为释放介质,采用高效液相色谱法测定甲睾酮聚乳酸微球的体外释药量。结果甲睾酮聚乳酸微球开始释药较快,存在一定突释效应,随后以缓慢的方式释药,可用双相动力学方程100-R=35.77e0.1321t+63.91e7.372E-4t描述。结论制成的甲睾酮聚乳酸微球具有明显的缓释作用。     

肺靶向卡铂明胶微球的药物动力学和体内分布研究

采用原子吸收分光光度法测定静脉给药后小鼠血浆和各脏器组织中卡铂的浓度,并对肺靶向卡铂明胶微球和游离药物卡铂的药物动力学、体内分布行为和肺靶向性进行了比较研究。结果表明卡铂明胶微球药物动力学模型为三室模型,具有明显的肺靶向性。     

2-亚氨基-2-甲氧基乙基-1-硫代-β-D-半乳吡喃糖苷的合成及其肝靶向应用研究

目的:合成具有肝靶向意义的2-亚氨基-2-甲氧基乙基-1-硫代-β-D-半乳吡喃糖苷,并考察其肝脏靶向性能.方法:以半乳糖为起始物,经乙酰化、溴代、缩合、置换,加醇后得目的化合物.小鼠尾静脉注射给药后,HPLC测定药物在小鼠肝脏及血液中的浓度.结果:目标化合物经IR和MS进行了结构确证.白蛋白微球表面偶联2-亚氨基-2-甲氧基乙基-1-硫代-β-D-半乳吡喃糖苷,肝靶向效率增大约1.5倍.结论:所制半乳糖白蛋白微球趋肝性能增强.     

聚(ε-己内酯) -聚乙二醇-聚(ε-己内酯)两亲三嵌段共聚物蛋白大分子药物微球的研究

目的:研究以聚(ε-己内酯) -聚乙二醇-聚(ε-己内酯) (PCE)制备蛋白大分子药物微球的方法及其与成品理化性质和释放动力学的关系。方法:采用复乳溶剂挥发法制备牛血清白蛋白(BSA) PCE微球,以扫描电镜观察微球的表面形态,以Mi-croBCA法测定微球载药量和包封率,以累积释放量考察微球体外释药特性。结果:微球外形圆整、表面光滑。不同分子量PCE微球载药量和包封率相近,但体外释药特性显著不同,释放机制为扩散-降解,其中PCE4000因扩散作用释出的蛋白量明显低于其它分子量所制微球。微球体外释药规律符合扩散-溶蚀(Q=k1t1/2+k2t+k3t2+k4t3)(r=0.997)方程。结论:以PCE制备蛋白大分子药物微球具有良好的缓释效果,突释小,释放完全。     

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。     

纳曲酮微球缓释制剂的药效学研究

本研究目的为观察纳曲酮微球缓释制剂抗吗啡镇痛和成瘾的药效学,药代动力学,组织相容性及生物降解性,为临床应用提供依据。通过小鼠热板法、大鼠甩尾法和吗啡依赖催促实验表明,纳曲酮微球缓释制剂单次皮下给药后对抗吗啡的镇痛作用和阻断小鼠吗啡躯体依赖形成的有效时间均达一个月以上,药代动力学研究证明,大鼠皮下给药有效血药浓度均能维持30天以上,注射局部的病理检查,无明显局部刺激反应,组织相容良好;在大鼠皮下微球约50天内完全降解。     

去甲斑蝥素白蛋白微球在小鼠体内肝靶向作用

目的:研究去甲斑蝥素(NCTD)白蛋白微球在小鼠体内的组织分布、体外细胞毒性及肝靶向性。方法:采用体外细胞毒性和体内全身急性毒性试验方法,评价NCTD白蛋白微球的抗肿瘤活性及其生物安全性;通过小鼠尾静脉给药得到各主要药动学参数,并与NCTD注射液组比较得其靶向效率。结果:NCTD白蛋白微球在肝脏和肾脏的靶向效率分别为2.389 1和0.375 4。NCTD白蛋白微球体内外的生物安全性与其注射液比较无显著差异。体外细胞毒性显示其对肿瘤细胞具有特殊亲和力和靶向释药作用。结论:NCTD白蛋白微球具有肝脏靶向性,能降低肾脏分布,提高药物疗效,降低全身不良反应。     

雾化吸入羟基喜树碱在小鼠体内的药代动力学研究

目的:研究雾化吸入羟基喜树碱(HCPT)在小鼠体内和肺中以及其他脏器中的药代 动力学特征.方法:采用HPLC法测定不同时间点小鼠血浆和肺组织以及其他脏器组织中羟基喜树碱的内酯和盐型的浓度,并对雾化吸入给药后的血浆和各个脏器组织中的药物浓度数据进行药代动力学分析.结果:雾化吸入给药后,肺组织中的浓度远远高于血浆和其他器官组织,血浆和其他器官组织中药物浓度较低,并且在肺组织中,内酯型比例较高.结论:雾化吸入羟基喜树碱在肺癌中能达到靶器官中的高浓度和血浆中的低浓度,两者的药物动力学规律有所不同.     

肺靶向米托蒽醌明胶微球的研究

采用二步法制备米托蒽醌明胶微球,球径范围为5.1～25.0μm的占总数87.36%,体外释药与原药相比t1/2延长4倍,DTA曲线上的特征吸热峰为133℃,经37℃,RH75%考察3月,几乎无变化。经小鼠体内分布试验表明具有明显的肺靶向性,靶向效率增加3～35倍,肺中药代动力学行为可用一室开放模型描述,平均滞留时间延长10h。     

YIGSR聚合衍生物对B16黑色素瘤细胞实验性肺转移的抑制作用

目的 :研究Tyr-Ile-Gly-Ser-Arg(YIGSR )均叉、杂叉聚合肽的抗肿瘤转移作用。方法 :观察药物对B16黑色素瘤细胞实验性肺转移的影响。结果 :尾静脉接种B16黑色素瘤细胞第21天 ,46例对照组和实验组小鼠肺转移瘤灶形成比例100 %。10例对照组小鼠平均肺转移结节数105 5±78 2。与瘤细胞共注射的适宜剂量YIGSR均叉、杂叉肽可明显降低实验组小鼠的肺转移结节数 ,并呈一定的剂量依赖关系。其中 ,100μg～200μgYIGSR均叉和同剂量杂叉肽组肺转移结节数与对照组比较 ,P<0.05和P<0.01 ;50μg均叉肽与对照组比较 ,P<0.05。但受试合成肽未明显降低已形成肺转移小鼠的肺脏重量。结论 :YIGSR聚合衍生物有较强的抗肿瘤转移作用 ,其机制与瘤细胞栓塞、滞留于远隔靶器官的微血管中并增殖 ,瘤细胞穿出血管或淋巴管 ,在靶器官内形成微转移灶有关     

米托蒽醌白蛋白微球和联糖米托蒽醌白蛋白微球肝靶向性比较研究

目的：比较米托蒽醌白蛋白微球和联糖米托蒽醌白蛋白微球肝靶向性的优劣。方法：以小鼠为实验动物,以静脉注射给药后小鼠血浆及各器官中的米托蒽醌含量为指标。结果：联糖米托蒽醌白蛋白微球在肝中的分布高于米托蒽醌白蛋白微球,而且肝中米托蒽醌较高浓度的维持时间也更长。结论：联糖米托蒽醌白蛋白微球肝靶向性比米托蒽醌白蛋白微球好,但无统计学上的显著性差异。     

紫杉醇脂质体在大鼠和荷瘤裸鼠体内的组织分布

目的：运用LC—MS／MS法测定紫杉醇脂质体在大鼠和荷瘤裸鼠体内的组织分布,比较注射用紫杉醇脂质体和紫杉醇注射液的体内分布特征。方法：大鼠分组后分别iv．7mg·kg-1受试和参比试剂,于给药前、给药后10min、1h、4h采集组织样品;荷瘤裸鼠分组后分别iv．10mg·kg-1受试和参比试剂,于给药前、给药后10min,1h,4h,8h采集组织样品,利用LC—Ms／Ms法对组织样品中药物含量进行测定。结果：大鼠iv．紫杉醇脂质体后10min在肝、心、肾、脑、子宫分布达到最大值．4h后各组织中药物含量均下降：荷瘤裸鼠iv．给药后10min在血、肝、脾、肺、肾、脂肪、睾丸分布量最大,8h后在脾、肠、肝、肿瘤中药物含量依然较高。结论：紫杉醇脂质体和紫杉醇注射液在大鼠和裸鼠体内的组织分布一致。静脉注射紫杉醇脂质体后．均能特异地分布到肝脏、肺和肠等。两制剂比较,紫杉醇脂质体具有更好的靶向性和更高的安全性。     

茵陈素对肺癌细胞增殖和细胞周期的影响

目的 :探讨茵陈素对肺癌细胞增殖和细胞周期的影响。方法 :应用光镜、四氮甲唑蓝 (MTT)方法和流式细胞术分析茵陈素对肺癌细胞形态学、生长和细胞周期的变化。结果 :茵陈素能抑制肺癌细胞的增殖 ,呈剂量依赖性 ,以160μg/ml抑制作用最明显 ,抑制率达52 4 %。80μg/ml时 ,S期和G2/M期细胞比例开始下降 ,细胞被阻滞于G0/G1 期 ,不能进入S期及G2/M期 ,增殖指数明显下降。结论 :茵陈素在体外对肺癌细胞具有抑制作用 ,通过抑制DNA合成 ,将细胞阻滞于G0/G1 期来抑制细胞增殖。     

Preparation, characterization, and optimization of pancreas-targeted 5-Fu loaded magnetic bovine serum albumin microspheres

The magnetic bovine serum albumin (BSA) microspheres (MS) were prepared by emulsification/solidification method. In this experiment, two kinds of magnetic MS, e.g. BSA MS and PEG-incorporated BSA microspheres (PMS) were prepared. The obtained MS were characterized by Malvern laser particle sizer and scanning electron microscopy (SEM). The obtained MS were spherical and about 1.3 microm in size. The magnetic responsivity and in vitro release behavior of these MS were studied in detail. The in vivo distribution and targeting delivery of 5-fluorouracil (5-Fu) magnetic MS after artery administration were studied in rat. The results showed that PMS could efficiently delivery 5-Fu to the targeted site compared with BSA MS without PEG MS and free drug.     

Preparation,characterization, and optimization of pancreas-targeted 5-Fu loaded magnetic bovine serum albumin microspheres

The magnetic bovine serum albumin (BSA) microspheres (MS) were prepared by emulsification/solidification method. In this experiment, two kinds of magnetic MS, e.g. BSA MS and PEG-incorporated BSA microspheres (PMS) were prepared. The obtained MS were characterized by Malvern laser particle sizer and scanning electron microscopy (SEM). The obtained MS were spherical and about 1.3 μm in size. The magnetic responsivity and in vitro release behavior of these MS were studied in detail. The in vivo distribution and targeting delivery of 5-fluorouracil (5-Fu) magnetic MS after artery administration were studied in rat. The results showed that PMS could efficiently delivery 5-Fu to the targeted site compared with BSA MS without PEG MS and free drug.     

Diphtheria and tetanus toxoid microencapsulation into conventional and end-group alkylated PLA/PLGAs.

The feasibility of biodegradable polyester microspheres (MS) for single injection vaccines will greatly depend on the toxoid stability within the MS exposed to in vivo conditions. This study examined the effects of polymer type and co-encapsulated additives on diphtheria (Dtxd) and tetanus (Ttxd) toxoid entrapment and stability. The co-encapsulated stabilizers influenced significantly the entrapment of Dtxd and Ttxd in PLA/PLGA MS. Typically, 5% BSA or trehalose decreased the amount of Dtxd entrapped in spray-dried MS, whereas BSA increased the entrapment in coacervated MS. Further, the entrapment of Dtxd decreased as a function of polymer hydrophobicity in spray-dried MS. Without additives, approx. 64, 43 and 16% entrapment efficiency of ELISA-reactive antigen was obtained for 14-17 kDa PLGA 50:50, PLGA 75:25 and PLA, respectively. The novel end-group stearylated 1-PLAs were only processed by coacervation. Satisfactory entrapment of 30-60% Dtxd was obtained. Here, albumin was a prerequisite for toxoid encapsulation, as BSA-free formulations produced strong toxoid precipitation. Furthermore, protein burst release increased with the more hydrophobic polymers, with Dtxd, Ttxd and the co-encapsulated BSA following a similar pattern and magnitude. This investigation also revealed that the method of protein extraction from the microspheres (O/W-partition or polymer hydrolysis) as well as the analytical methods (HPLC or ELISA) strongly influenced the determined amount of encapsulated toxoid and BSA. In conclusion, the study revealed the complexity of antigen microencapsulation when using different preparation and analytical techniques, as well as different types of materials.     

Attempt to detect natural anticancer compounds--protein binding through precursor ion scan and MS/MS measurements

A 2'-succinyltaxol-bovine serum albumin (BSA) conjugate was prepared as an antigen to produce an anti-taxol monoclonal antibody by immunizing mice. Formation of a linkage between hapten and protein is usually confirmed by the UV or fluorescamine method. However, it was difficult to confirm the binding of 2'-succinyltaxol to BSA by these methods owing to the similar UV absorption maxima of 2'-succinyltaxol (273 nm) and BSA (280 nm). In the present study, we therefore conducted a mass spectrometric analysis using the precursor ion scan and MS/MS techniques to confirm the formulation of the 2'-succinyltaxol-BSA conjugate in the following way: The conjugate was subjected to thermal denaturalization, dithiothreitol (DTT)-reduction, iodoacetamide-alkylation and trypsin-digestion, affording a peptide fragment mixture. This was then analyzed by electrospray ionization (ESI)-MS in the positive mode by scanning the peaks containing a mass of 854 corresponding to taxol. The detected peaks were in turn subjected to MS/MS measurements. Among them, a peak at m/z 1247.4 was found to be a peptide fragment containing Lys (epsilon-2'-succinyltaxol), demonstrating the formulation of the 2'-succinyltaxol-BSA conjugate. In order to confirm the feasibility of this analytical method, the deacetylvinblastine (deacetylVLB)-BSA antigen which produced the anti-VLB monoclonal antibody (MAb-10-A9), was subjected to the same analytical treatment as above, giving a peak at m/z 851.3 originating from a Lys (epsilon-deacetylVLB). Thus, this new method could serve as an additional tool for confirmation of the formation of hapten-protein conjugates which are difficult to detect by the above spectrophotometric methods.     

超高效液相色谱-串联质谱法测定大鼠血浆及组织中贝达喹啉浓度及其药动学考察

目的:建立超高效液相色谱-串联质谱(UPLC-MS/MS)法测定SD大鼠血液及组织中贝达喹啉的浓度,研究其在大鼠体内的药动学及组织分布.方法:采用UPLC-MS/MS联用技术,测定大鼠血液及组织中贝达喹啉的药物浓度,并利用DAS软件及非房室模型统计矩方法计算药动学参数.结果:贝达喹啉线性范围为0.1～500 ng·mL...     

Evaluation of poly(d,l-lactide-co-glycolide) microspheres for the lung-targeting of yuanhuacine,a novel DNA topoisomerase I inhibitor

The present study was intended to develop poly(d,l-lactide-co-glycolide) (PLGA; 50:50, 0.15 dL/g) microspheres (MS) loaded with yuanhuacine (YHC) for passive targeting in lung as well as providing a simple evaluation method for the targeting efficiency of MS. A kind of photochromic spiropyran dye was applied to label MS to clearly demonstrate the in vivo distribution characteristics through intravenous injection into mice and rabbits. Sections of 10-μm thickness from different organs were cut using a microtome, and fluorescent microscopy was used to determine the biodistribution of the MS. The average particle size of MS was 9.0 μm, and the glass transition temperature was 37–40°C. In vitro, the cumulative release achieved 50.8% in 24 h. Histological sections from different organs indicated that the amount of MS in lung achieved maximum in 6 h, as about 8 times as in liver and 70 times higher than the average concentration of other organs. In vivo, MS were gradually swelled and drug concentration remained just 10% in 12 h, which would not result in long time embolization in the lung. This evaluation method supplies a simple and visualized channel in focus for the targeting efficiency of PLGA MS.