肺靶向阿奇霉素脂质体的制备及其在小鼠体内的分布

目的研究肺靶向阿奇霉素阳离子脂质体的制备方法并考察其在小鼠体内的分布。方法利用旋转薄膜-冻融法制备肺靶向阿奇霉素脂质体。用高效液相色谱法测定给药后小鼠体内各组织中的药物浓度。结果制得的脂质体平均粒径为6.582 μm，表面电荷为+19.5 mV，包封率大于75%，稳定性好。药物体外释药符合Higuchi方程。小鼠尾静脉给药后，阳离子脂质体主要被肺摄取，在肺部的滞留时间明显延长，AUC值约为阿奇霉素溶液的8.4倍。结论采用薄膜-冻融法，添加十八胺可制得具有较高包封率及稳定性的阿奇霉素阳离子脂质体，在小鼠肺部的分布优于注射液，能达到肺靶向目的。     

羟基喜树碱脂质体的制备及其包封率测定

目的:制备符合肺靶向要求的羟基喜树碱脂质体并测定其包封率。方法:采用薄膜分散-冻融法制备羟基喜树碱脂质体;用凝胶柱色谱法分离游离药物;高效液相色谱法测定包封率。采用ZORBAX SB-C18柱(4.6mm×250mm,5μm),以75mmol.L-1醋酸铵-5mmol.L-1三乙胺(冰醋酸调pH至5.6)缓冲液/乙腈(75∶25)为流动相,流速1mL.min-1,检测波长383nm,柱温30℃。结果:制得的脂质体平均粒径大于2μm,包封率大于70%。在选定的色谱条件下,羟基喜树碱与辅料能完全分离,在0.2~20mg.L-1范围内,药物浓度与峰面积呈良好的线形关系(r=0.9998)。结论:薄膜分散-冻融法适用于制备肺靶向羟基喜树碱脂质体;凝胶柱-高效液相色谱法操作简单,准确,重复性好,可用于测定羟基喜树碱脂质体的含量和包封率。     

肺靶向吡非尼酮脂质体的制备及体外释药性质研究

目的：研究肺靶向吡非尼酮脂质体的制备方法并考察其体外释药性质。方法：采用薄膜分散法制备吡非尼酮脂质体;用D-甘露糖修饰脂质体并添加适量十八胺调节脂质体表面电荷;用紫外分光光度法测定包封率;用正交实验优化处方,用透析法考察药物体外释放性质。结果：制得的脂质体平均粒径为581.1nm,表面电荷为-20.61mV,包封率为81.1%,稳定性好。药物体外释药符合Weibull方程。结论：采用薄膜分散法,用D-甘露糖修饰并添加十八胺可制得具有较高包封率及稳定性的吡非尼酮脂质体,有助于提高吡非尼酮的肺靶向性。     

羟基喜树碱脂质体的制备与性质研究

目的：确定羟基喜树碱脂质体的制备工艺。方法：利用薄膜分散-超声法制备羟基喜树碱脂质体,并对制备得到的脂质体进行粒径、稳定性和体外释放的评价。结果：制备到得平均粒径为较小,并具有一定缓释效果的羟基喜树碱脂质体。结论：薄膜分散-超声法适用于制备粒径均一、包封率较高HCPT脂质体。     

载羟基喜树碱聚乳酸微球的制备与体外释药研究

目的:研究载羟基喜树碱的聚乳酸微球的制备方法并考察其体外释药性质。方法:以PLA为成膜材料,采用改良乳化-溶剂挥发法,制备载羟基喜树碱的聚乳酸微球并优化制备工艺;对载药微球进行表征;超声介导下进行载药微球的体外释药试验。结果:微球粒径在1～7μm,大小均一;羟基喜树碱浓度在10mg.mL-1下,载药微球包封率为62.2%,载药量为1.69%;药物体外释药符合Higuchi方程。结论:采用乳化-溶剂挥发法,以PLA为成膜材料可制得具有较高包封率的羟基喜树碱微球,有望实现降低羟基喜树碱给药量、减少不良反应,提高靶向性的目标。     

羟基喜树碱微球的制备及其小鼠体内分布研究

目的:制备肺靶向性羟基喜树碱(HCPT)微球,评价其体外释药特性及其在小鼠体内的肺靶向性。方法:以聚乳酸为主要辅料,采用溶剂挥发法制备微球,考察其粒径、包封率、载药量,比较微球及原料药的体外释药性;取12只小鼠分别尾静脉注射HCPT微球及原料药,30min后分别测定血浆及各组织的药物浓度并计算相对分布率。结果:所制微球粒径在7～30μm者达81.6%,平均粒径为(14.2±3.1)μm,包封率为72.36%,载药量为(40.6±3.6)%,微球及原料药体外释药参数T50分别为85、18min。微球给药组在肺中的药物浓度最高(32.2±2.48)μg.mL-1,相对分布率58.1%;原料药给药组在血浆中的药物浓度最高(13.52±2.58)μg.mL-1,相对分布率25.24%。结论:所制HCPT微球具有明显的缓释性及肺靶向性。     

羟基喜树碱纳米粒在大鼠体内的药动学、组织分布及靶向性研究

目的:研究羟基喜树碱纳米粒在大鼠体内的药动学及组织分布特征,并探讨其靶向性。方法:将雄性SD大鼠随机分为两组,每组6只,分别单剂量尾静脉注射羟基喜树碱纳米粒和市售羟喜树碱注射液(4 mg/kg,以羟基喜树碱计),在给药后5、30、60、120、240、360、480、600、720 min时于眼底静脉丛取血500μL,采用高效液相色谱法测定不同时间点血浆中羟基喜树碱的含量,以DAS 3.0等软件计算药动学参数。另取雄性SD大鼠随机分为两组,每组24只,分别单剂量尾静脉注射羟基喜树碱纳米粒和市售羟喜树碱注射液(0.6 mg/kg,以羟基喜树碱计),在给药后30、60、120、240 min时于腹主动脉取血并摘取心、肝、脾、肺、肾、脑,采用高效液相色谱法测定不同时间点血浆及组织中羟基喜树碱的含量,考察其分布特征及靶向性。结果:羟基喜树碱纳米粒和市售羟喜树碱注射液在大鼠体内均符合二室模型,羟基喜树碱纳米粒的AUC0-720 min和AUC0-∞分别为市售羟喜树碱注射液的1.89和1.87倍,MRT0-720 min和MRT0-∞为2.74和3.00倍,t1/2β为2.75倍,组间比较差异均有统计学意义(P<0.05);给药后30 min时,羟基喜树碱纳米粒和注射液在肺中浓度最高;随着时间的推移,药物逐渐向肝部位积累,在60 min时肝药浓度达到最高。羟基喜树碱纳米粒在肝的相对摄取率最大(6.28);以肝为靶向器官,其在心、脾、肺、肾、脑和血浆中的靶向效率均大于羟喜树碱注射液;给药后30~120 min,羟基喜树碱纳米粒在心、肺(除给药后30 min外)、肾、脑、血浆中的选择性指数均显著高于羟喜树碱注射液(P<0.05或P<0.01)。结论:羟基喜树碱纳米粒延长了药物的半衰期、提高了其血药浓度、延长了其体内作用时间,且肝靶向性显著。     

羟基喜树碱脂质体的制备及质量评价研究

目的:制备羟基喜树碱(HCPT)脂质体,并对其质量进行评价.方法:采用薄膜分散-高压乳匀法制备羟基喜树碱脂质体;用激光粒度分析仪测定其Zeta电位、粒径大小;考察其在0.9%NaCl溶液、水、5%葡萄糖溶液中8 h的稳定性;用凝胶柱层析法考察包封率;采用薄膜透析法考察体外释药性质.结果:羟基喜树碱脂质体Zeta电位为(-33.1±1.3) mV,平均粒径(182.5±5.6) nm,8 h内在水、5%葡萄糖溶液中稳定性良好;包封率(91.2±1.2)%;体外释药曲线符合Higuchi方程Q=1.291 6t1/2 0.309 8,r=0.980 3.结论:本试验制备的羟基喜树碱脂质体稳定性好,大小均匀, 包封率高,并具有延缓药物释放的性质.     

支链淀粉修饰双嘧达莫脂质体的制备及其在小鼠体内的组织分布

目的研究支链淀粉修饰双嘧达莫(DIP)脂质体的制备方法并考察其在小鼠体内的组织分布。方法 采用薄膜-分散法制备普通DIP脂质体；合成两亲性的棕榈酰化支链淀粉并用其修饰DIP脂质体；比较修饰前后包封率、zeta电位、平均粒径和径距的变化；采用反相高效液相法测定小鼠组织中的DIP浓度。结果修饰后DIP脂质体的包封率降低，zeta电位增加，平均粒径和径距无明显变化；普通脂质体可以增强DIP在肺部、肝脏和脾脏的分布，而较之普通脂质体，支链淀粉修饰的脂质体可以进一步增加肺部DIP水平，同时减少DIP在肝脏和脾脏的分布，并延长在肺部的滞留时间。结论与普通脂质体和注射液比较，支链淀粉修饰的脂质体可以改变DIP在小鼠体内的组织分布，具有显著的肺靶向性。     

羟喜树碱脂质体的制备及在犬体内的药动学研究

采用溶剂注入-高压均质法制备羟喜树碱脂质体.结果显示,本品平均粒径为(182.5±5.6)nm,ζ电位为-(33.10±0.56)mV,包封率大于90%.以市售注射液为参比制剂,采用单剂量双周期交叉试验考察静脉给药后羟喜树碱脂质体在Beagle犬体内的药动学行为.结果表明,羟喜树碱经脂质体包裹后可维持较高的血药浓度,延长了药物在体内的消除时间.     

RGD环肽介导的靶向脂质体体内药动学及荷瘤动物活体成像研究

本文测定了大鼠单剂量(5 mg.kg1)尾静脉注射RGD环肽介导的羟基喜树碱(hydroxycamptothecin,HCPT)靶向脂质体(HCPT-RGD-LP)和HCPT长循环脂质体(HCPT-LP)的血药浓度,比较两组的药动学行为;研究了HCPT-LP及HCPT注射剂在正常小鼠血浆和心、肝、脾、肺、肾中的分布情况;采用人肝癌HepG2细胞移植裸鼠,以DiR为荧光探针,通过活体成像比较RGD环肽修饰的DiR靶向脂质体(DiR-RGD-LP)和DiR长循环脂质体(DiR-LP)在荷瘤裸鼠体内的分布。结果显示,HCPT-RGD-LP组和HCPT-LP组的主要药动学参数t1/2β、CL、Vc、AUC048 h、AUC0∞、MRT048 h和MRT0∞均无显著性差异(P>0.05);HCPT-LP在小鼠体内的循环时间明显长于HCPT注射剂,且药物在肝脏中的分布浓度较高;荷瘤裸鼠中,DiR-RGD-LP组肿瘤部位的荧光强度显著高于DiR-LP组,提示RGD环肽用于脂质体修饰能明显提高给药系统的肿瘤靶向性。     

聚乙二醇修饰的羟基喜树碱纳米脂质载体的制备及其小鼠组织分布

本研究采用熔融乳化-高压均质法制备了聚乙二醇(PEG)修饰的羟基喜树碱(HCPT)纳米脂质载体(HCPT-PEG-NLC)及非修饰的羟基喜树碱纳米脂质载体(HCPT-NLC)，并考察了其形态、粒径及包封率。测定了HCPT注射液、HCPT-PEG-NLC及HCPT-NLC 3种制剂经小鼠尾静脉注射后在血浆、心、肝、脾、肺、肾及卵巢等主要组织的浓度，评价了HCPT-PEG-NLC及HCPT-NLC在各组织的靶向性效果。透射电镜下观察，HCPT-PEG-NLC及HCPT-NLC呈球形；测得平均粒径分别为(88.6±22.5)和(127.2±43.4)nm；包封率分别为(90.51±3.29)%和(84.37±2.81)%。经小鼠尾静脉注射后，HCPT-PEG-NLC及HCPT-NLC在多数取样时间点的血药浓度较HCPT注射液有所提高，HCPT在各组织中的消除半衰期明显延长。HCPT-NLC蓄集于网状内皮系统(RES)，在肝、脾的相对摄取率(R_e)和峰浓度比(C_e)明显高于HCPT-PEG-NLC。HCPT-PEG-NLC延长了药物在血浆中的滞留时间，提高了生物利用度，MRT及AUC_{0-24 h}分别为注射液的19.80和17.02倍，并且与HCPT-NLC比较显著降低了RES的吞噬作用，在肺部表现出明显的靶向作用(R_e及C_e分别为14.51，41.35)。综上，HCPT-PEG-NLC可延长HCPT的体内循环时间，呈现明显的肺靶向性，有望作为HCPT肺癌治疗的理想载体。     

Hydroxycamptothecin liposomes based on thermal and magnetic dual-responsive system: preparation,in vitro and in vivo antitumor activity,microdialysis-based tumor pharmacokinetics

Due to the absence of lactone form of hydroxycamptothecin, the commercially available hydroxycamptothecin injection exhibits inefficient therapeutic effects. In this study, we constructed a novel delivery system (thermosensitive magnetic liposomes) that protects lactone form of hydroxycamptothecin from blood or water. After hydroxycamptothecin was loaded into the thermosensitive magnetic liposome (HCPT/TML), its in vitro and in vivo antitumor activity and microdialysis-based tumour pharmacokinetics were determined. The results demonstrated that HCPT/TMLs possessed favourable physicochemical features and significant cytotoxicity against the Huh-7 cells in vitro. In the in vivo antitumor study and tumour pharmacokinetics, HCPT/TMLs displayed effective targeting delivery and antitumor effects, which corresponded to the determined hydroxycamptothecin concentration in tumour tissue. In conclusion, this thermal and magnetic dual-responsive system can efficiently deliver hydroxycamptothecin to tumour tissue and has great potential application in cancer treatment.     

Characteristics and biodistribution of soybean sterylglucoside and polyethylene glycol-modified cationic liposomes and their complexes with antisense oligodeoxynucleotide

A novel cationic liposome modified with soybean sterylglucoside (SG) and polyethylene glycol-distearoylphosphatidylethanolamine (PEG-DSPE) as a carrier of antisense oligodeoxynucleotide (ODN) for hepatitis B virus (HBV) therapy was constructed. Characteristics of the cationic liposomes modified with SG and PEG (SG/PEG-CL) and their complexes with 15-mer phosphorothioate ODN (SG/PEG-CL-ODN complex) were investigated by incorporation efficiency, morphology, electrophoresis, zeta potentials, and size analysis. Antisense activity of the liposomes and ODN complexes was determined as hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) in HepG₂ 2.2.15 cells by ELISA. Their tissue and intrahepatic distribution were evaluated following intravenous injection in mice. The complexes gained high incorporation efficiency and intact vesicular structure with mean size at ∼200 nm. The SG/PEG-CL-ODN complexes enhanced the inhibition of both HBsAg and HBeAg expression in the cultured HepG₂ 2.2.15 cells relative to free ODN. The uptake of SG/PEG-CL and nonmodified cationic liposomes (CL) was primarily by liver, spleen, and lung. Furthermore, the concentration of SG/PEG-CL was significant higher than that of CL in hepatoctyes at 0.5 hr postinjection. The biodistribution of SG/DSPE-CL-ODN complex compare with free ODN showed that liposomes enhanced the accumulation of ODN in the liver and spleen, while decreasing its blood concentration. SG/PEG-CL-mediated ODN transfer to the liver is an effective gene delivery method for cell-specific targeting, which has a potential for gene therapy of HBV infections. SG and PEG-modified cationic liposomes have proven to be an alternative carrier for hepatocyte-selective drug targeting.     

N-三甲基壳聚糖包覆水飞蓟宾脂质体在小鼠体内的药动学及靶向性

目的:研究N-三甲基壳聚糖(TMC)包覆的水飞蓟宾脂质体(SLBL)在小鼠体内药动学,并对其肝靶向性进行研究。方法:小鼠尾静脉注射水飞蓟宾(SLB)溶液、SLBL、季铵化程度为20%的TMC包覆的SLBL(TMC20-SLBL),HPLC法检测不同时间血浆和各组织中SLB的浓度,采用DAS2.0软件统计学方法分析SLB在小鼠体内的药动学特征,采用相对摄取率re进行肝靶向性评价。结果:3种制剂中的SLB在小鼠体内的药动学特征符合二室模型,t_1/2β顺序依次为:SLBL>TMC20-SLBL>SLB溶液,AUC大小顺序为TMC20-SLBL>SLBL>SLB溶液,CL顺序为SLB溶液>SLBL>TMC20-SLBL。SLBL和TMC20-SLBL在肝组织的相对摄取率r_e分别为4.101和9.706。结论:与SLB溶液及SLBL相比,TMC20-SLBL具有明显的缓释作用及肝靶向性,生物利用度较高,有利于提高其治疗作用。     

In-vivo pharmacokinetics, tissue distribution and anti-tumour effect of hydroxycamptothecin delivered in oil-in-water submicron emulsions

Objectives The aim of this study was to investigate the pharmacokinetics, tissue distribution and anti‐tumour effect of hydroxycamptothecin submicron emulsions (HCPT‐SEs). Methods HCPT‐SEs or HCPT injection (HCPT‐I) was administered intravenously into the tail vein of rats or S180 tumour‐bearing mice. Key findings HCPT‐SEs increased the plasma concentration of HCPT compared with HCPT‐I at all time points. The AUC_0‐∞, elimination half‐life and mean residence time of anionic submicron emulsions containing HCPT (HCPT‐ASEs) and cationic submicron emulsions containing HCPT (HCPT‐CSEs) were significantly greater than those of HCPT‐I (P < 0.01). Especially, a prolonged elimination half‐life was found for HCPT‐CSEs. HCPT‐CSEs and HCPT‐ASEs resulted in a 7.9‐fold and 3.1‐fold increase in AUC_0‐6h of tumour compared with HCPT‐I, respectively. The targeting efficiency (T_e) of HCPT‐ASEs and HCPT‐CSEs indicated their selectivity to tumour and the T_e of HCPT‐CSEs was significantly higher than that of HCPT‐ASEs (P < 0.01). The anti‐tumour effect studies showed that HCPT‐SEs improved the therapeutic efficiency of HCPT compared with HCPT‐I. The percentage of tumour growth suppression rate of mice treated with HCPT‐CSEs (2.0 mg HCPT eq./kg) increased 2.1 fold compared with that of HCPT‐I. Conclusions Submicron emulsions can alter the pharmacokinetic characteristics and tissue distribution of HCPT, and enhance tumour targeting and anti‐tumour activity.     

Development and validation of a sensitive reversed-phase HPLC method to determine intracellular accumulation of hydroxycamptothecin

The intracellular accumulation of anti-cancer agents strongly influences the efficiency of chemotherapy for cancer. In the present study, a simple, rapid, sensitive reversed-phase high-performance liquid chromatographic (RP-HPLC) method was developed and validated to determine hydroxycamptothecin (HCPT) in Eca109 cells. HCPT in cellular lysis solution were measured by RP-HPLC with a C18 column after extraction with ethyl acetate. The mobile phase contained 0.1% triethylamine-phosphoric acid buffer (pH 3.0) and acetonitrile (75:25, v/v). Fluorescence detector with excitation and emission wavelengths of 382 and 528 nm was used for determination of HCPT. The calibration curve was linear from 2 to 100 ng/ml with correlation coefficient of 0.9999, while the limit of quantification is 2 ng/ml. The recovery of assay was between 86.5 and 105.2%. The intra- and inter-day coefficients of variation were less than 10% (R.S.D.). Furthermore, the validated method was used to determine the accumulation of HCPT after incubating the liposomal formulation of HCPT and HCPT for injection with the intact cells. HCPT liposomes showed higher intracellular accumulation of HCPT at different incubation times compared with that of conventional HCPT injection.     

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.