汉防己甲素聚乳酸微球小鼠肺靶向研究

目的 :研究汉防己甲素聚乳酸微球的肺靶向性。方法 :分别对小鼠尾静脉注射汉防己甲素聚乳酸微球和汉防己甲素注射剂 ,以反相高效液相色谱法测定并比较小鼠各组织中汉防己甲素的浓度。结果 :汉防己甲素在血浆中检测浓度范围为0 .519～17 000μg/ml(r=0. 9996) ,加样回收率为97 .32 % ,相对标准差平均值为4 .46 % ;应用汉防己甲素聚乳酸微球后汉防己甲素在小鼠各组织中浓度明显高于汉防己甲素注射剂 ;汉防己甲素在小鼠肺中浓度明显高于其它组织。结论 :汉防己甲素聚乳酸微球具有明显的肺靶向性。     

星点设计法优化汉防己甲素壳聚糖微球的处方

目的:星点设计法优化汉防己甲素壳聚糖微球的处方,提高该制剂的肺靶向性。方法:采用乳化交联法制备壳聚糖微球,自变量为汉防己甲素和壳聚糖的重量比、水相和油相的体积比、壳聚糖浓度,以微球收率、载药量、包封率、平均粒径和跨距为因变量对各自变量的各水平进行多元线性回归和二项式拟合,选择较佳工艺条件并对优化区间进行预测分析。结果:收率、载药量、包封率、平均粒径和跨距用二项式模型拟合较好,最佳优化制备处方的汉防己甲素和壳聚糖的重量百分比为61·97%,水相和油相的体积比为13·51%,壳聚糖浓度为2·37%。结论:星点设计可用于优化制剂处方,所制汉防己甲素壳聚糖微球粒径大小适宜,可满足肺靶向的要求。     

汉防己甲素肺靶向聚乳酸微球兔体内药动学的研究

目的:为汉防己甲素肺靶向聚乳酸(TET -PLA)微球的体内代谢研究提供科学依据。方法:采用兔耳缘静脉注射给药、颈动脉取血方式,以反相高效液相色谱法测定血样中的汉防己甲素浓度;应用3p87药动学程序进行房室模型拟合,计算药动学参数。结果:汉防己甲素在家兔体内药动学过程呈二房室模型,t1/2β为(286. 49±237. 55)min ,AUC为(810. 33±287 .49) (μg·min)/ml。结论:TET -PLA微球在兔体内具有缓释作用。     

肺靶向汉防己甲素缓释微囊的长期毒性研究

目的：为肺靶向汉防己甲素（TET）缓释微囊临床研究提供依据。方法：以正常大鼠组,生理盐水组和该微囊的高,中,低剂量给药组进行试验。将给药后大鼠的体征,血液学生化学指标及病理组织学特征等作为指标,进行肺靶向缓释微囊混悬注射液的长期毒性评价。结果：与正常大鼠组,生理盐水组和TET微囊低剂量组的各项指标表明三者均无明显改变,高剂量组所产生的异常变化经停药后,基本恢复正常,结论：肺靶向汉防己甲素缓释微囊基本安全,可用于临床研究。     

汉防己甲素聚乳酸微球的安全性评价

目的:评价汉防己甲素聚乳酸微球(TET-MC)的安全性。方法:采用液中干燥法制备TET-MC,对TET-MC进行急性毒性、血管刺激性、肌肉刺激性、过敏性试验。结果:小鼠静脉注射TET-MC的半数致死量为158.9mg·kg-1;未观察到TET-MC对实验动物有血管刺激性、过敏性,但有轻微的肌肉刺激性。结论:汉防己甲素微球化后毒性降低,应用于受试动物安全性较好。     

应用人工神经网络结合遗传算法优化汉防己甲素壳聚糖微球制备工艺

目的:优化汉防己甲素壳聚糖微球的制备工艺参数。方法:应用人工神经网络建模结合遗传算法寻优,确定反应温度、搅拌速率、乳化剂浓度、交联剂用量,提高微球载药量、包封率,优化微球粒径,降低跨距,实现微球制备工艺参数及其多指标的同步优化。结果:优化的模型结果为反应温度18.2℃、搅拌速率1167.6r·min-1、乳化剂浓度12.2%、交联剂用量1.5mL,微球的载药量43.2%、包封率49.5%,粒径8.6μm、跨距1.0,验证试验数据与模型优化预测结果吻合。结论:应用人工神经网络建模结合遗传算法寻优,可以实现汉防己甲素壳聚糖微球的制备工艺参数及其多指标的同步优化。     

汉防己甲素固体分散片的制备及处方优化

目的:优选汉防己甲素固体分散片的制备处方。方法:采用直接压片法制备汉防己甲素固体分散片。采用单因素试验筛选常用辅料,以崩解时间为指标,以交联聚乙烯吡咯烷酮(PVPP)用量、乳糖-微晶纤维素比例、微粉硅胶用量为因素,采用正交试验对处方进行优化,并进行验证。比较所制片剂与汉防己甲素普通片的溶出度,测定最优处方所制片剂的含量。结果:最优处方为以9.5%PVPP为崩解剂、乳糖-微晶纤维素(1∶2)为填充剂,混匀,加入1%的微粉硅胶为润滑剂,粉末直接压片。所制3批片剂的崩解时间分别为79、81、78 s,占标示量百分含量分别为98.66%、99.24%、99.85%,RSD分别为0.72%、1.16%、1.33%。与汉防己甲素普通片比较,所制片剂的溶出度明显提高。结论:成功制得汉防己甲素固体分散片,且处方合理、重复性好。     

肺靶向贝母素甲明胶微球的制备

目的制备肺靶向贝母素甲明胶微球,并对其理化性质进行考察。方法采用乳化—化学交联法制备贝母素甲明胶微球;采用光学显微镜对微球形态、粒度分布等进行考察;利用柱前衍生HPLC方法测微球的包封率和载药量;利用透析法考察微球体外释药特性。结果在光学显微镜下观察,微球呈球形,表面光滑,很少黏连,平均粒径10.72μm,粒径在5～25μm范围内的微球占总数的85.8%,载药量为5.128%,包封率为66.35%,体外释药具有缓释特征。结论微球的粒径、形态、载药量和包封率、体外释药性能等基本符合肺部靶向的要求。     

汉防己甲素纯化工艺的优化

目的:优化汉防己甲素的纯化工艺,选取最优纯化方法,制备高纯度的汉防己甲素。方法:采用大孔吸附树脂和硅胶柱层析分离,再使用陶瓷膜超滤脱色,最后重结晶的方法,以汉防己甲素的收率和纯度为指标,对汉防己甲素的纯化工艺进行优化。结果:汉防己甲素的最佳纯化工艺如下：粉防己药材乙醇回流提取的粗粉,经XR982C型大孔吸附树脂吸附,90%乙醇洗脱,然后硅胶层析,二氯甲烷：乙酸乙酯：三乙胺(90∶20∶0.1)体系洗脱,再经过孔径5 nm的氧化铝无机陶瓷膜超滤,最后使用乙醇过饱和溶液重结晶,得到高纯度的汉防己甲素,含量大于99.5%,达到注射用原料要求,可用于注射剂的制备。结论:本纯化工艺稳定、可行,设备要求简单,摒弃大量有毒溶媒的使用,具备很大的工业化生产潜力。     

肺靶向汉防己甲素缓释胶囊的安全性评价

目的：探讨肺靶向汉防己甲素缓释微囊的安全性。方法：用白蛋白为囊材，以“喷雾干燥－热变性”法制备肺靶向汉防己甲素缓释微囊（TET－MC），进行急性毒性，长期毒性，体外溶血试验，过敏性试验以及局部刺激性试验。结果：小鼠静脉注射和腹腔注射的LD50分别为83．56和594.29mg/kg，与原药比分别大了150％和140％，体外溶血3h无溶血和凝集现象，无刺激性和过敏反应，大鼠腹腔注射连续21d给药部位未见异常，低剂量组各实质性器官细胞未见细胞学病变，中，高剂量组的异常情况在停药2wk后恢复正常。结论：汉防己甲素经微囊化后毒性明显降低，表明TET－MC基本安全。     

肺靶向硫酸链霉素明胶微球的制备

目的:用生物可降解材料明胶制备肺靶向硫酸链霉素明胶微球.方法:用乳化法制备微球,正交试验设计考察影响制备工艺的因素,用扫描电子显微镜观察微球表面形态,用红外光谱分析确证含药微球的形成.并对所制备的硫酸链霉素明胶微球的粒径及其分布、载药量、包封率、稳定性等进行了研究.结果:微球形态圆整,药物确己存于微球中.微球的平均粒径为12.269 μm,粒径在5.0～25.0 μm的微球占总数的91.5%,达到肺靶向要求.载药量为42.6%,包封率为53.8%.最佳工艺条件重现性好.经37℃、RH75%放置3个月,其含量、外观形态及大小基本不变.结论:该微球制备工艺稳定,可用于肺靶向注射剂的研究.     

肺靶向利福平聚乳酸微球的研制

采用分散－溶媒扩散法制备肺靶向利福平聚乳酸微球，考察了不同因素对微球粒径大小及分布的影响：分散搅拌速度加快，粒径减小；聚乳酸、利福平浓度升高，粒径增大；有机溶剂对粒径的作用取决于其与甘油的相溶性。相溶性高，粒径小，吐温－８０不溶于甘油，因而不影响微球粒径。     

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。     

异烟肼肺靶向性微球的制备及其小鼠体内分布

目的：制备异烟肼肺靶向性微球,评价其体外释药特性及在动物体内的肺靶向性。方法：采用溶剂挥发法制备微球,动态透析法考察其体外释药性能,实验动物静脉注射后测定其各组织的药物浓度,研究其体内相对分布百分率及肺靶向性。结果：制得的微球粒径在7～30μm的占微球总数的88．8％,平均粒径为（16.7±4．6）μm,包封率为86．92％,载药量为（40．7±3.6）％（n=5）,体外释药T50为68min,轻对照组延长了4.5倍。动物实验表明,制得微球后,药物在肺内的相对分布百分率明显高于其它组织与血液,并轻对照组提高了4倍。结论：本法制得的异烟肼微球具有明显的缓释性及肺靶向性。     

Passive targeting and lung tolerability of enoxaparin microspheres for a sustained antithrombotic activity in rats

Pulmonary bed can retain microparticles (MP) larger than their capillaries’ diameter, hence we offer a promising way for lung passive targeting following intravenous (IV) administration. In this study, enoxaparin (Enox)-albumin microspheres (Enox-Alb MS) were, optimally, developed as lung targeted sustained release MP for IV use. Lung tolerability and targeting efficiency of Enox-Alb MS were tested, and the pharmacokinetic profile following IV administration to albino rats was constructed. In vivo studies confirmed high lung targeting efficiency of Enox-Alb MS with lack of potential tissue toxicity. The anticoagulant activity of the selected Alb MS was significantly sustained for up to 38?h compared to 5?h for the market product. Alb MS are promising delivery carriers for controlled and targeted delivery of Enox to the lungs for prophylaxis and treatment of pulmonary embolism.     

Preparation and testing of cefquinome-loaded poly lactic-co-glycolic acid microspheres for lung targeting

The aim of this study was to prepare cefquinome-loaded poly lactic-co-glycolic acid (PLGA) microspheres and to evaluate their in vitro and in vivo characteristics. Microspheres were prepared using a spry drier and were characterized in terms of morphology, size, drug-loading coefficient, encapsulation ratio and in vitro release. The prepared microspheres were spherical with smooth surfaces and uniform size (12.4?±?1.2?μm). The encapsulation efficiency and drug loading of cefquinome was 91.6?±?2.6 and 18.3?±?1.3%, respectively. In vitro release of cefquinome from the microspheres was sustained for 36?h. In vivo studies identified the lung as the target tissue and the region of maximum cefquinome release. A partial lung inflammation was observed but disappeared spontaneously as the microspheres were removed through in vivo decay. The sustained cefquinome release from the microspheres revealed its applicability as a drug delivery system that minimized exposure to healthy tissues while increasing the accumulation of therapeutic drug at the target site. These results indicated that the spray-drying method of loading cefquinome into PLGA microspheres is a straightforward method for lung targeting in animals.     

Preparation and the in-vivo evaluation of paclitaxel liposomes for lung targeting delivery in dogs

Objectives The aim of this study was to develop paclitaxel liposomes for a lung targeting delivery system. Methods The liposomes composed of Tween‐80/HSPC/cholesterol (0.03 : 3.84 : 3.84, mol/mol), containing paclitaxel and lipids (1 : 40, mol/mol), were prepared by a combination of solid dispersion and effervescent techniques, and then subjected to ultrasonication. The pharmacokinetics and biodistribution of liposomal and injectable formulation of paclitaxel in dogs were studied after intravenous administration. Key findings The mean diameter, polydispersity index, zeta‐potential and entrapment efficiency of the liposomes were 501.60 ± 15.43 nm, 0.28 ± 0.02, ?20.93 ± 0.06 mV and 95.17 ± 0.32%, respectively. The liposomal formulation kept stable for at least 3 months at 6 ± 2°C and didn't cause haemolysis. The liposome carrier decreased the area under the curve and terminal half‐life of paclitaxel compared with paclitaxel injection ranging from 0.352 ± 0.031 mg/l*h and 0.0671 ± 0.144 h to 0.748 ± 0.062 mg/l*h and 1.978 ± 0.518 h, respectively. The paclitaxel liposomes produced a drug concentration in the lung that was markedly higher than that in other organs or tissues and was about 15‐fold of that of paclitaxel injection at 2 h. Conclusions To sum up, these results demonstrated that the paclitaxel liposomes are an effective lung targeted carrier in the treatment of lung cancer.     

Sophoridine-loaded PLGA microspheres for lung targeting: preparation,in vitro,and in vivo evaluation

Lung-targeting sophoridine-loaded poly(lactide-co-glycolide) (PLGA) microspheres were constructed by a simple oil-in-oil emulsion-solvent evaporation method. The obtained microspheres were systematically studied on their morphology, size distribution, drug loading, encapsulation efficiency, in vitro release profile, and biodistribution in rats. The drug-loaded microparticles showed as tiny spheres under SEM and had an average size of 17?μm with 90% of the microspheres ranging from 12 to 24?μm. The drug loading and encapsulation efficiency were 65% and 6.5%, respectively. The in vitro drug release behavior of microspheres exhibited an initial burst of 16.6% at 4?h and a sustained-release period of 14 days. Drug concentration in lung tissue of rats was 220.10?μg/g for microspheres and 6.77?μg/g for solution after intraveneous injection for 30?min, respectively. And the microsphere formulation showed a significantly higher drug level in lung tissue than in other major organs and blood samples for 12 days. These results demonstrated that the obtained PLGA microspheres could potentially improve the treatment efficacy of sophoridine against lung cancer.     

紫杉醇壳聚糖肺靶向微球的制备

目的研制具有肺靶向性的紫杉醇壳聚糖微球,并对处方工艺进行优化。方法以壳聚糖为载体,采用乳化一化学交联法制备紫杉醇壳聚糖微球。单因素试验考察了油／水体积比、紫杉醇浓度、乳化时间、乳化剂量等因素,采用正交设计优化微球制备工艺,以HPLC法测定微球载药量、包封率。结果制得的微球显微观察形态圆整、表面光滑,无黏连;平均粒径为（8．23±0．25）μm,粒径在7～12μm平均占微球总数的84．2％,载药量为16．20％±1．15％,包封率为81．29％±1．62％。结论筛选的最佳处方工艺制备的微球粒径大小适宜,可满足肺靶向微球的要求并免除过敏试剂的加入。     

Micro- and nanocarrier-mediated lung targeting

Importance of the field: Drug delivery to lungs appears to be an attractive proposition on account of the large surface area of the alveolar region; it provides tremendous opportunities to improve drug therapies both systemically and locally using new drug delivery systems. Administration of drugs directly to the lungs is the most appropriate route in the treatment of asthma and other pulmonary diseases such as tuberculosis, chronic obstructive pulmonary disease and lung cancer.

Areas covered in this review: This review focuses on the utilization of nano- and microcarriers such as microspheres, nanoparticles, liposomes, niosomes and dendrimers for targeted delivery of bioactive molecules to lungs.

What the reader will gain: This review sheds light on the current status of nano- and microcarrier-mediated lung targeting of bioactive compounds.

Take home message: The literature review shows that carriers could supplement sustained drug delivery to the lungs, extended duration of action, reduced therapeutic dose, improved patient compliance, and reduced adverse effects of highly toxic drugs. There is still a need to identify more specific receptors that are present exclusively in the lungs. The identification of such receptors may also facilitate drug targeting to further specific parts of the lungs, such as bronchioles and alveoli.