重组降血压肽缓释微球的制备与体外释放

目的采用复乳溶剂蒸发法制备重组降血压肽(rAHP)缓释微球。方法以聚乳酸(PLA)为缓释材料,利用正交设计优化微球制备的最佳工艺条件,并考察了微球的体外释药特性。结果微球制备的最优工艺为:油相中PLA的浓度为7.5%、初乳搅拌速度为900 r/min、内水相与油相体积比为1∶10,外水相聚乙烯醇124浓度为5%;按此工艺制备的微球粒径跨度小、分布均匀,包封率为81.35%,载药量在10.92%,微球得率在80.26%,微球的平均粒径分布范围在75～80μm之间;载药微球在磷酸盐缓冲液中0.5 h内的累积释药量为17.5%,第15天累积释药率达到98.6%。结论该微球制备工艺成熟,包封率高,符合我国药典对缓释制剂的指导原则要求。     

Preparation and characterization of poly(dl-lactide-co-glycolide) nanoparticles for siRNA delivery

Synthetic short interfering RNA (siRNA) is promising for specific and efficient knockdown of disease-related genes. However, in vivo application of siRNA requires an effective delivery system. Commonly used siRNA carriers are based on polycations, which form electrostatic complexes with siRNA. Such poly- or lipoplexes are of limited use in vivo due to severe problems associated with toxicity, serum instability and non-specific immune-responses. The aim of the present study was to prepare uniformly sized nanoparticles (NPs) with a high load of siRNA by use of the safe and biodegradable poly-(dl-lactide-co-glycolide) (PLGA) polymer without including polycations. The siRNA was encapsulated in the core of NPs by the double emulsion solvent evaporation method. To optimize the NP formulation, the effects of important formulation and processing parameters were investigated systematically. Generally, spherical siRNA-loaded NPs (<300 nm, PDI < 0.2, zeta potential −40 mV) were obtained. An encapsulation efficiency of up to 57% was achieved by adjusting the inner water phase volume, the PLGA concentration, the first emulsification sonication time, and stabilization of the water–oil interface with serum albumin. The integrity of siRNA was preserved during the preparation. Preparation of core-loaded siRNA-NPs based on PLGA and no cationic excipient seems possible and promising for delivery of siRNA.     

利福喷丁/聚乳酸-羟基乙酸纳米粒的制备及处方工艺优化

目的： 研制负载利福喷丁的聚乳酸-羟基乙酸共聚物[poly（lactic-co-glycolic acid）,PLGA]纳米粒,并对其处方及制备工艺进行优化。方法： 采用快速膜乳化法制备利福喷丁/PLGA纳米粒。通过单因素实验考察了乳化剂浓度、PLGA浓度、油相/水相体积比、初乳制备转速、初乳制备时间、过膜压力、过膜次数对纳米粒制备的影响。在此基础上以粒径、载药率、包封率为评价指标,使用正交实验设计对纳米粒制备的处方工艺进行优化,以TOPSIS法进行多指标综合分析。然后对最优处方工艺进行验证,并对载药纳米粒的体外释药行为进行考察。结果： 经最优处方工艺制备的载药纳米粒,粒径（428±11.4）nm,粒径分布为（0.186±0.036）,包封率为（76.89±2.6）%,载药率为（10.89±1.2）%。用透视电镜观察呈均匀分布的球形。在体外药物释放实验中,药物在72 h内累计释放了78.81%。结论： 采用快速膜乳化可以简单快捷地制备均匀圆整、包封性好、具有良好缓释性能的利福喷丁/PLGA纳米粒,并为新型抗结核精准治疗的开发提供了基础。     

盐酸表柔比星-聚乳酸-羟基乙酸共聚物纳米粒的制备

摘要目的制备盐酸表柔比星 聚乳酸 羟基乙酸（PLGA）共聚物纳米粒,对其进行质量评价。方法采用乳化 溶剂挥发法制备盐酸表柔比星纳米粒;对主要处方因素如PLGA用量、外水相中聚山梨酯 80用量、泊洛沙姆188和聚山梨酯 80比例进行正交设计,以药物的包封率、载药量和药物利用率等为考察指标。结果采用优化后处方制得的纳米粒药物包封率为（32.6±1.2）%,载药量为（7.2±0.5）%,药物利用率为（51.6±3.4）%,纳米粒平均粒径166.6 nm,药物可持续160 h释放。结论该方法制备盐酸表柔比星纳米粒工艺简单,无需使用聚乙烯醇,药物释放缓慢。     

Influences of process parameters on nanoparticle preparation performed by a double emulsion pressure homogenization technique

The preparation of nanoparticles (NP) as an improved colloidal carrier system for proteins was investigated. Bovine serum albumin (BSA) was used as model drug. Owing to the high solubility of the protein in water, the double emulsion technique has been chosen as one of the most appropriate method. In order to both reaching submicron size as well as increasing the grade of monodispersity compared to previous preparation techniques, a microfluidizer as homogenization device was used. All experiments were performed using two biodegradable polymers, poly[D,L-lactic-co-glycolic acid] 50/50 (PLGA) and poly[epsilon-caprolactone] (PCL). The homogenization procedure has been optimized with regard to particle size and monodispersity by studying the influence of the homogenization time as well as the amount of polymer and surfactant in the external aqueous phase. The drug loading has been improved by varying the concentration of the protein in the inner aqueous phase. By increasing the protein concentration in the inner aqueous phase the polydispersity was slightly higher, while the particle size was not influenced significantly. The BSA encapsulation efficiency decreased with higher protein concentration in the inner aqueous phase. All release profiles were characterized by a initial burst effect, a higher release rate was obtained after 4 weeks for PLGA NP (60%) compared with PCL NP (47%).     

携siRNA的丙交酯乙交酯共聚物-壳聚糖纳米载体的制备与表征

目的 通过引入壳聚糖增加丙交酯乙交酯共聚物（PLGA）载体中小干扰RNA（siRNA）的包封率,对制备的携siRNA-壳聚糖（siRNA-CS）的PLGA纳米载体（siRNA-CPG）进行表征。方法 选用传统的乳化-溶剂挥发法制备siRNACPG,以粒径、Zeta电位及包封率为指标,对处方（siRNA与壳聚糖质量比,PLGA质量浓度,内水相、二氯甲烷、外水相的体积比）进行单因素考察及星点设计-响应面法优化。对优化后制备的siRNA-CPG进行粒径、Zeta电位、包封率质量评价;根据粒径及包封率考察siRNA-CPG在生理盐水及血清中的稳定性;制备荧光标记的siRNA-CPG,与MCF-7细胞孵育4 h,观察细胞摄取情况。结果 壳聚糖的引入可将siRNA包封率从3.14%提高到90%以上。优化后的处方中壳聚糖、siRNA、PLGA质量浓度分别为1、0.5、10 mg·mL^-1,内水相、二氯甲烷、外水相的体积比为1∶10∶100。制备3批siRNA-CPG冻干粉,复溶后室温放置48 h及血清中24 h内粒径和包封率均无明显变化;siRNA-CPG可被细胞摄取并从溶酶体中逃逸出来。结论 制备的siRNA-CPG包封率高、稳定性好,可以实现siRNA的细胞质有效递送。     

复乳法制备阿柔比星A的聚乳酸聚乙醇酸共聚物纳米粒影响包封率因素考察

以含阿柔比星A(Aclarubicin A，ACRB-A)的酸性溶液为内水相，采用复乳法制备ACRB-A(PLGA)纳米粒。考察了有机溶剂、油酸的量、稳定剂种类、投药量、乳化剂、Na2SO4的量和外水相的pH值几个主要因素对ACRB-APLGA纳米粒包封率的影响。结果表明，以二氯甲烷和丙酮为有机溶剂、油酸(15mg)、右旋糖酐-70、ACRB-A的浓度(Smg／ml)、以F68和Tween-80为乳化剂、2％的Na2SO4和外水相的pH等于8有利于提高ACRB-A的包封率。经实验条件优化后制备的ACRB-A PLGA包封率为85．41％，纳米粒粒径为272nm，粒径分散指数为0．213。     

Sustained release of low molecular weight heparin from PLGA microspheres prepared by a solid-in-oil-in-water emulsion method

Biodegradable poly(lactic-co-glycolic acid) (PLGA) microspheres for the sustained release of low molecular weight heparin (LMWH) were prepared by a soild-in-oil-in-water (s/o/w) emulsion method. Prior to encapsulation, the LMWH micro-particles were fabricated by a modified freezing-induced phase separation method. The micro-particles were subsequently encapsulated into PLGA microspheres. Process optimization revealed that the NaCl concentration in the outer phase of s/o/w emulsion played a critical role in determining the properties of the microspheres. When the NaCl concentration increased from 0% to 5%, the encapsulation efficiency significantly increased from 51.5% to 76.8%. The initial burst release also decreased from 37.3% to 12.4%. In vitro release tests showed that LMWH released from PLGA microspheres in a sustained manner for about 14 days. Single injection of LMWH-loaded PLGA microspheres into rabbits resulted in an elevation of an anti-factor Xa activity for about 6 days. Furthermore, the integrity of the encapsulated LMWH was preserved during encapsulation process.     

Preparation and characterization of hCG-loaded polylactide or poly(lactide-co-glycolide) microspheres using a modified water-in-oil-in-water (w/o/w) emulsion solvent evaporation technique

A modified w/o/w emulsion solvent evaporation technique was adopted to prepare human Chorionic Gonadotropin (hCG)-loaded polylactide (PLA) or poly(lactide-co-glycolide) (PLGA) microspheres. The effects of preparative parameters, such as stirring rate, polymer MW and concentration, and the composition of both the inner aqueous phase and oil phase etc., on hCG entrapment efficiency and microsphere characteristics were investigated. It was found that by adding 20% glycerol into the inner aqueous phase and 40% acetone into the oil phase, smooth microspheres 1mum in diameter could be produced with high hCG entrapment efficiency (&gt;90%). In vitro release test showed a burst release of hCG from PLGA (75:25) microspheres, followed by sustained release of 55% hCG over 2 months. The initial hCG burst from PLGA microspheres increased with the glycerol concentration in the inner aqueous phase, but decreased to a low value (ca. 20%) with the addition of acetone into the oil phase, which could beattributed to the associated changes in surface morphology of the microspheres. In vivo experiments demonstrated that a single shot of hCG-loaded PLGA microspheres could produce a comparable antibody response with the inoculation of free hCG four times.     

艾塞那肽聚乳酸-羟基乙酸共聚物纳米粒的制备及其分析方法研究

目的 以聚乳酸-羟基乙酸共聚物（PLGA）为载体,用乳化复乳法制备包载艾塞那肽（EX）的PLGA纳米粒（EX-PLGA NPs）,并对其分析方法进行研究。方法 2018年10月至2019年8月,采用Box-Behnken Design(BBD)响应面分析法对纳米粒制备的处方工艺进行优化,动态光散射技术检测EX-PLGA NPs粒径和Zeta电位;通过高效液相色谱法（HPLC）测定EX-PLGA NPs中艾塞那肽含量并进行方法学验证。结果 制备的EX-PLGA NPs粒径为（157.2±3.1）nm,Zeta电位为（-19.5±2.6）mV;载药量和包封率分别为（4.41±0.28）%和（73.43±0.59）%,透射电镜图显示纳米粒外观圆整,分布均匀;EX-PLGA NPs体外稳定性良好,透析袋法释放结果显示其具有缓释效果。结论 制备的EX-PLGA NPs粒径分布均一,包封率和载药量高,稳定性好,艾塞那肽含量分析方法科学有效,为艾塞那肽抗糖尿病口服缓释制剂的分析和开发提供了实验基础。     

Comparison of process parameters for microencapsulation of plasmid DNA in poly(D,L-lactic-co-glycolic) acid microspheres

Poly(D,L-lactic-co-glycolic) acid (PLGA) microspheres containing plasmid DNA encoding the firefly luciferase gene were prepared using the water-in-oil-in-water (w/o/w) double emulsion and solvent evaporation method. In this study, we investigated the effects of three process parameters on DNA microencapsulation: (1) emulsification method used to generate the primary emulsion, (2) water/oil ratio during formation of the first emulsion, and (3) surfactant concentration used in the preparation of the second emulsion. The resulting formulations were also analyzed for microsphere size, encapsulation efficiency, and kinetics of DNA release. We found that although each process alteration resulted in encapsulation of biologically active, structurally intact DNA, the surfactant and water/oil ratio significantly affected the size, release kinetics and encapsulation efficiency of plasmid DNA.     

Preparation and characterization of hCG-loaded polylactide or poly(lactide-co-glycolide) microspheres using a modified water-in-oil-in-water (w/o/w) emulsion solvent evaporation technique

A modified w/o/w emulsion solvent evaporation technique was adopted to prepare human Chorionic Gonadotropin (hCG)-loaded polylactide (PLA) or poly(lactide-co-glycolide) (PLGA) microspheres. The effects of preparative parameters, such as stirring rate, polymer MW and concentration, and the composition of both the inner aqueous phase and oil phase etc., on hCG entrapment efficiency and microsphere characteristics were investigated. It was found that by adding 20% glycerol into the inner aqueous phase and 40% acetone into the oil phase, smooth microspheres approximately 1 microm in diameter could be produced with high hCG entrapment efficiency (>90%). In vitro release test showed a burst release of hCG from PLGA (75:25) microspheres, followed by sustained release of 55% hCG over 2 months. The initial hCG burst from PLGA microspheres increased with the glycerol concentration in the inner aqueous phase, but decreased to a low value (ca. 20%) with the addition of acetone into the oil phase, which could be attributed to the associated changes in surface morphology of the microspheres. In vivo experiments demonstrated that a single shot of hCG-loaded PLGA microspheres could produce a comparable antibody response with the inoculation of free hCG four times.     

Sustained release of low molecular weight heparin from PLGA microspheres prepared by a solid-in-oil-in-water emulsion method

Biodegradable poly(lactic-co-glycolic acid) (PLGA) microspheres for the sustained release of low molecular weight heparin (LMWH) were prepared by a soild-in-oil-in-water (s/o/w) emulsion method. Prior to encapsulation, the LMWH micro-particles were fabricated by a modified freezing-induced phase separation method. The micro-particles were subsequently encapsulated into PLGA microspheres. Process optimization revealed that the NaCl concentration in the outer phase of s/o/w emulsion played a critical role in determining the properties of the microspheres. When the NaCl concentration increased from 0% to 5%, the encapsulation efficiency significantly increased from 51.5% to 76.8%. The initial burst release also decreased from 37.3% to 12.4%. In?vitro release tests showed that LMWH released from PLGA microspheres in a sustained manner for about 14 days. Single injection of LMWH-loaded PLGA microspheres into rabbits resulted in an elevation of an anti-factor Xa activity for about 6 days. Furthermore, the integrity of the encapsulated LMWH was preserved during encapsulation process.     

姜黄素-PLGA纳米粒提高口服给药生物利用度的研究

目的 研究乳酸/羟基乙酸共聚物（PLGA）纳米粒子提高姜黄素口服生物利用度。方法 采用乳液挥发法制备姜黄素-PLGA纳米粒;通过透射电镜（transmission electron microscope,TEM）观察纳米粒形态;采用动态光散射法（dynamic light scattering,DLS）测定纳米粒大小、表面电位（Zeta电位）;考察药物的体外稳定性以及药物释放行为;以大鼠口服灌胃给药方式考察姜黄素和姜黄素-PLGA纳米粒的体内药物生物利用度。结果 姜黄素-PLGA纳米粒粒度分布均匀,平均粒径大小约200 nm;姜黄素-PLGA纳米粒具有较高的载药量和包封率以及稳定性,体外药物释放实验结果显示具有一定的缓释效果;口服灌胃100 mg·kg^-1姜黄素和姜黄素-PLGA纳米粒,给药30 min之后,姜黄素-PLGA纳米粒给药组的血药浓度水平显著高于姜黄素组（P〈0.05）,药物生物利用度提高到原来的5.2倍。结论 姜黄素-PLGA纳米粒可以有效的提高姜黄素稳定性和口服给药生物利用度。     

Preparation and in vivo pharmacokinetics of rhGH-loaded PLGA microspheres

Recombinant human growth hormone (rhGH) therapy must be administered as a daily injection due to its short half-life. To achieve sustained release of rhGH, the preparation of rhGH-loaded PLGA microspheres was investigated, and the influence of various factors on encapsulation efficiency was tested, including rhGH concentration, the ratio of internal phase to organic phase, stirring speed, PVA concentration, surrounding pH value, and the type of emulsifier and organic solvent. A pharmacokinetic study was performed by subcutaneous administration to explore the sustained release effect. It was found that rhGH-loaded PLGA microspheres were prepared with a narrow size distribution, and optimization of the formulation could enhance encapsulation efficiency. FTIR analysis indicated that the activity of rhGH was maintained after encapsulation. The pharmacokinetic behavior of rhGH solutions was consistent with a two-compartment model, which showed fast absorption and distribution. RhGH-loaded PLGA microspheres achieved a higher bioavailability and a long-term effective concentration by controlling the release, and PLGA 50/50 demonstrated favorable AUC compared with PLGA 75/25. Nevertheless, the higher bioavailability of rhGH-loaded PLGA microspheres lacking Span 80 did not predicate better sustained release behavior, indicating that further investigation is needed to explore the use of bioavailability as the standard in evaluating the sustained release characteristics and in vivo behavior of microspheres.     

改良自乳化-溶剂扩散法制备甲基莲心碱纳米粒的研究

目的制备甲基莲心碱纳米粒(NEF-NP),并采用正交试验设计对甲基莲心碱纳米粒制备工艺进行优化。方法以包封率和载药量为评价指标,采用聚乳酸-羟基乙酸共聚物(PLGA)为载体,丙酮-无水乙醇为有机溶剂,通过正交设计优化改良自乳化-溶剂扩散法制备载NEF的PLGA载药纳米粒的处方工艺。结果优化的最佳处方工艺为:PLGA的浓度为20 mg.mL-1,NEF的投药量为3.3 mg,PVA浓度为1.0%,水相与有机相的体积比为8∶1。最佳条件下制得的纳米粒平均包封率达(70.35±1.16)%,载药量(2.33±1.08)%,平均粒径为(213.5±2.7)nm。结论最佳处方工艺制备的NEF-PLGA纳米粒具有较高的包封率、载药量和较小的粒径。     

牛血清白蛋白阳离子微球的制备及体外评价

目的制备牛血清白蛋白（BSA）口服阳离子微球,考察天然阳离子物质壳聚糖（CHS）的加入对蛋白微球的粒径、电动电势、包封率、载药量及体外释放情况的影响。方法以乳酸／羟基乙酸共聚物（PLGA）和壳聚糖（CHS）为载体材料,采用W／O／W复乳-溶剂挥发法制备牛血清白蛋白乳酸／羟基乙酸共聚物-壳聚糖（PLGA／CHS）阳离子微球。通过正交设计优化制备工艺,确定最佳处方。建立准确而简便的蛋白含量测定方法,并对微球进行体外评价。结果最佳处方为：BSA浓度为150g·L^-1、PLGA浓度为8％、外水相体积为80mL、壳聚糖浓度为0．2％。制得的微球形态圆整,平均粒径为（6．9±5．5）μm,为表面荷正电的阳离子微球[ζ电势=00．0±0．6）mV],包封率为（75．4±4．6）％,载药量为（9．3±0．2）％。体外释放结果表明,在模拟胃液和模拟肠液中,壳聚糖的加入均能减少突释,延缓药物的释放。结论与PLGA微球相比,制得的PLGA／CHS阳离子微球表面带正电,具有较高的包封率和载药量,可以延缓药物释放,同时减少突释现象。     

P物质多囊脂质体的制备工艺优化及相关性质考察

目的:优化P物质多囊脂质体的制备工艺,并考察其相关性质。方法:复乳法制备P物质多囊脂质体,以包封率为指标,磷脂与胆固醇的摩尔比(A)、超声乳化时间(B)、初乳与二相小的体积比(C)、辅助乳化剂的浓度(D)为因素进行正交试验设计,优化其制备条件;对优化条件所制脂质体进行包封率、粒径分布、体外释药性能、相转变温度和熔点的考察。结果:优化制备条件A为2:1,B为30 s,C为1:2,D为2%;所制多囊脂质体包封率可达85%,粒径分布为0.75～27.75μm,在生理盐水中释药t_(1/2)=11 h,可持续72 h释药,相转变温度为34℃,熔点为110℃。结论:所制P物质多囊脂质体包封率高,物理性能稳定,是一种较为理想的缓释制剂。     

利福布汀-PLGA纳米粒的制备

目的:制备利福布汀(RB)-聚乳酸-羟基乙酸共聚物(PLGA)纳米粒,并对制备工艺进行优化。方法:采用改良的自乳化溶剂挥发法制备;通过单因素法考察对包封率影响较大的因素,在此基础上以包封率为指标采用正交设计优化纳米粒的制备工艺并进行验证。结果:对纳米粒包封率影响较大的因素是RB与PLGA投药比、PLGA浓度、混合有机相中丙酮比例及油水相比;上述各因素的最佳水平分别是1:2、40mg·mL-1、70%、1:5。验证试验中所制纳米粒平均粒径为(201±19)nm、包封率为(59.1±5)%、载药量为(15.1±2.4)%。结论:本文的制备方法简单,所得纳米粒粒径小、质量稳定。     

复乳法制备胰岛素PLGA纳米粒影响包封率因素考察

以Poloxamer188为乳化剂，乙酸乙酯为有机溶剂，采用复乳法制备了胰岛素乳酸／羟基乙酸共聚物（PLGA）纳米粒，考察了乳化剂和PLGA的浓度。内水相中胰岛素的浓度为pH，溶剂挥发方法和内水相中加入聚乙烯醇（PVA）等实验各因素对胰岛素PLGA纳米粒包封率的影响。结果表明，乳化剂的浓度较高，PLGA的浓度较小，内水相的pH接近胰岛素的pI(5．3），胰岛素的浓度较低，缩短有机溶剂挥发时间及内水相中加入PVA有利于提高胰岛素的包封率，经实验条件优化后制备的胰岛素PLGA纳米纳平均粒径为149．6nm，多分散性系数小于0．1，包封率提高到42．8％。