2种单硬脂酸甘油酯固体脂质纳米粒制剂的体内组织分布及药动学研究

目的:研究单硬脂酸甘油酯固体脂质纳米粒(MSLN)和经聚乙二醇2000(PEG2000)修饰后的MSLN(PEG-MSLN)在小鼠体内的组织分布及其在大鼠体内的药动学,考察PEG2000修饰对MSLN体内组织分布及药动学的影响。方法:采用溶剂扩散法制备MSLN,测定其粒径和Zeta电位;以罗丹明B为荧光标记物,测定和计算2种MSLN制剂经鼠尾静脉注射后的体内组织分布及药动学参数。结果:2种MSLN制剂粒径分布相似,Zeta电位约为—20mV;经鼠尾静脉注射后,MSLN靶向肝脏,且经PEG2000修饰后的纳米粒体循环时间可显著延长至2·2倍。结论:MSLN经PEG2000修饰后可改善体循环,其可作为肝脏靶向的药物载体。     

2种单硬脂酸甘油酯固体月旨质纳米粒制剂的体内组织分布及药动学研究

目的：研究单硬脂酸甘油酯固体脂质纳米粒（MSLN）和经聚乙二醇2000（PEG2000）修饰后的MSLN（PEG～MSLN）杠小鼠体内的组织分布厦其在大鼠体内的药动学，考察PEG2000修饰对MSLN体内组织分布厦药动学的影响。方法：采用溶刑扩散法制备MSLN，测定其粒径和Zeta电位；以罗丹明B为荧光标记物，测定和计算2种MSLN制剂经鼠尾静脉注射后的体内组织分布及药动学参数。结果：2种MSLN制荆粒径分布相似，Zeta电位约为一20mV；经鼠尾静脉注射后，MSLN靶向肝脏，且经PEG2000修饰后的纳米粒体循环时间可显著延长至2．2倍。结论：MSLN经PEG2000修饰后可改善体循环，其可作为肝脏靶向的药物载体。     

辛伐他汀固体脂质纳米粒的制备及在大鼠体内的药动学研究

摘 要 目的： 制备辛伐他汀固体脂质纳米粒,并研究其经灌胃给药后在大鼠体内的药动学特征。方法: 采用热熔乳化超声 低温固化法制备辛伐他汀固体脂质纳米粒,考察辛伐他汀固体脂质纳米粒的粒径分布、Zeta电位、包封率、微观形态及体外药物释放特性。研究辛伐他汀固体脂质纳米粒经灌胃给药后在大鼠体内的药动学特征。结果: 辛伐他汀固体脂质纳米粒平均粒径为(242.5±62.1) nm,多聚分散系数为0.225±0.031,Zeta电位为(-32.1±4.2) mV,包封率为(95.7±2.6) %,在24 h内平稳缓慢释药。辛伐他汀固体脂质纳米粒在大鼠体内的Cmax和AUC0 t分别为辛伐他汀混悬液的2.89倍和1.83倍。结论:辛伐他汀固体脂质纳米粒在大鼠体内能快速吸收,显著提高了药物在大鼠体内的生物利用度。     

聚乙二醇修饰青蒿素脂质纳米粒冻干工艺优化及其表征

目的筛选聚乙二醇(PEG)修饰青蒿素脂质纳米粒(PEG-ART-NLC)最优冻干保护剂处方,研究其冷冻干燥工艺及质量表征。方法制备含不同冻干保护剂的PEG-ART-NLC冻干粉,以外观、再分散性、复溶后外观、粒径、Zeta电位为指标,优化保护剂处方,并对比冻干前后脂质纳米粒质量变化。结果 4%甘露醇和4%蔗糖具良好的保护作用和再分散性,冻干后纳米粒粒径增大14.0 nm,Zeta电位绝对值降低8.8 m V,包封率降低14.5%,电镜下冻干前后纳米粒形态均为圆形或椭圆形,无明显差异。结论 4%甘露醇和4%蔗糖为最优保护剂处方,可用于制备稳定的PEG-ART-NLC冻干粉。     

紫杉醇PLGA纳米粒大鼠生物利用度的测定

目的制备紫杉醇PLGA纳米粒,以紫杉醇注射液为参比制剂,进行生物利用度考察。方法以乳化-溶剂挥发法制备紫杉醇纳米粒,用HPLC法测定全血中的药物浓度,计算紫杉醇纳米粒的生物利用度。结果紫杉醇纳米粒外观圆整,平均粒径为99.0nm,Zeta电位58.3mV,平均包封率为56.77%,载药量为7.10%。大鼠口服给药后,紫杉醇纳米粒的绝对生物利用度达到19.5%。结论纳米载药系统的制备有利于促进紫杉醇的吸收,提高了其口服生物利用度。     

壳聚糖修饰的托氟啶固体脂质纳米粒的制备

摘 要 目的： 研究托氟啶固体脂质纳米粒及壳聚糖修饰的托氟啶固体脂质纳米粒的制备方法。方法: 采用薄膜 超声分散法制备托氟啶固体纳米脂质粒（TFu-SLNs）及壳聚糖修饰的TFu-SLNs,并对纳米粒的形态、粒径和表面电位进行测定,通过单因素考察及正交设计优化制备方法,同时考察处方稳定性。结果: 薄膜 超声分散法制备的TFu-SLNs平均粒径为160.2 nm,Zeta电位为－33.12 mV,壳聚糖修饰TFu-SLNs平均粒径为400.3 nm,Zeta电位为+12.87 mV。经壳聚糖修饰后,随着壳聚糖浓度的增加,电位逐渐增大。优化后的处方重复性、稳定性良好。结论:通过采用正交设计法对TFu固体脂质纳米粒处方进行优化,得到TFu固体脂质纳米粒及壳聚糖修饰的TFu固体脂质纳米粒的优化处方。     

表面修饰的鼻用聚乳酸载药纳米粒的制备及体外性质研究

目的 研究壳聚糖盐酸盐、吐温80、聚乙二醇20000、冰片薄荷低共溶物多重修饰的茴拉西坦聚乳酸鼻腔给药脑靶向纳米粒的制备工艺,并初步评价其体外稳定性.方法 采用溶剂扩散-蒸发法制备多重修饰的载药纳米粒,筛选并优化了其处方,考察了粒径分布、Zeta电位、包封率、载药量、稳定性及体外累积释药百分率.结果 壳聚糖盐酸盐、吐温80、聚乙二醇20000三重修饰的纳米粒形态圆整,粒径分布141.5±30.4 nm,Zeta电位20.4 mV,包封率98.14％,载药量为11.57％.所制纳米粒在溶菌酶和大鼠鼻洗液中稳定,在pH7.4和pH4.0的磷酸盐缓冲液中的24 h内累计释药百分率小于88％.结论 壳聚糖盐酸盐、吐温80、聚乙二醇20000、冰片薄荷低共溶物多重修饰的载药纳米粒包封率较高,性质稳定.     

羧甲基壳聚糖-聚乙二醇作为胰岛素载体的研究

目的：制备胰岛素-羧甲基壳聚糖-聚乙二醇纳米粒。方法：利用红外光谱（FTIR）和核磁共振氢谱（¹H-NMR）对羧甲基壳聚糖-聚乙二醇的结构进行表征,用粒度分析仪测定纳米粒的粒径分布及电位,采用动态透析法考察纳米粒的释药性能,用CCK-8试剂盒检测纳米粒细胞毒性,以糖尿病小鼠为模型,研究纳米粒的降血糖作用。结果：聚乙二醇成功接枝到羧甲基壳聚糖上,包埋胰岛素的纳米粒的平均粒径为（257.5±12.1）nm,Zeta电位为（-15.2±0.3）mV,负载胰岛素的羧甲基壳聚糖-聚乙二醇纳米粒在中性释放介质中,5 h内胰岛素的释放速度较快,之后8 h趋于平稳,胰岛素的累计释放量可达到80%,CCK-8试剂盒显示纳米粒对L929细胞基本无细胞毒性,50 U·kg^-1的纳米粒溶液经灌胃给药后,血糖浓度明显降低。结论：胰岛素-羧甲基壳聚糖-聚乙二醇纳米粒基本无毒性,具有良好的生物相容性,对糖尿病小鼠有效发挥降血糖作用。     

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。     

薄膜-超声法制备芦丁固体脂质纳米粒的研究

目的优化薄膜-超声法制备芦丁固体脂质纳米粒的处方。方法以包封率为指标,采用正交设计优化法考察硬脂酸和大豆卵磷脂的用量、吐温-80和聚乙二醇-400的体积分数对包封率的影响,优选最佳处方。用透射电镜观察外观形态,用电位/纳米粒度分析仪分析纳米粒的粒径及Zeta电位,用透析法评价体外释药特征。结果以最佳处方制备的芦丁固体脂质纳米粒呈类球形,平均粒径为195.8±11nm,Zeta电位为-20.65±0.6mV,平均包封率为86.31%,72h体外累积释放87.32%。结论按最佳处方工艺制备的芦丁固体脂质纳米粒具有较高的包封率和较好的缓释效果。     

Cellular uptake of solid lipid nanoparticles and cytotoxicity of encapsulated paclitaxel in A549 cancer cells

The aim of this study was to investigate the cellular uptake of solid lipid nanoparticles (SLN) and cytotoxicity of its paclitaxel delivery system. The conjugate of octadecylamine-fluorescein isothiocyanate (ODA-FITC) was synthesized, and used as a marker to prepare fluorescent SLN. The cellular uptakes of fluorescent SLN with different lipid material were evaluated by fluorescence microscopy and the measurement of fluorescence intensity. The order of cellular uptake ability was glycerol tristearate SLN>monostearin SLN>stearic acid SLN>Compritol 888 ATO SLN (ATO888 SLN). The cellular cytotoxicities of paclitaxel were highly enhanced by the encapsulation of lipid matrix. Due to the lower drug entrapment efficiency of glycerol tristearate SLN, monostearin SLN was considered as the best lipid material to improve the cytotoxicity of drug. The polyethylene glycol monostearate (PEG-SA) and the synthesized conjugate of folic acid-stearic acid (FA-SA) were further introduced into monostearin SLN, respectively. The PEG and folate modified SLN could enhance the cellular uptake of SLN and the cellular cytotoxicity of drug by the membrane disturb ability of PEG chains on the SLN surface and the improved endocytosis mediated by folate receptor.     

Effect of PEG2000 on drug delivery characterization from solid lipid nanoparticles

The purpose of this work is to develop a PEG2000-modified solid lipid nanoparticles (SLN) intended to encapsulate a drug within their matrix and to study their characteristics. In the present report, drug-loaded SLN were prepared by a novel solvent diffusion method in an aqueous system. Monostearin and PEG2000 were used as carrier material and modifying agent, respectively. The model drug salbutamol sulphate was incorporated to study the characterization of entrapment efficiency, size, zeta potential (charge) and drug delivery characterization. In the test solution of pH 7.2 phosphate buffer, drug-release behavior from SLN suspension exhibited a biphasic pattern. With the monoastearin-based SLN, a distinctly prolonged release over a monitored period of 14 days was observed after a burst drug release in the first 8 hours. Over the monitored period of prolonged release, there was delayed release in the first 5 days with nearly 2.51% of the drug released each day, following which a slightly higher release rate (8.14% per day) appeared in the last 9 days. In contrast, the drug release rate from PEG2000-modified SLN was faster. Nevertheless, further work is required in order to optimize the release behavior of various entrapped drugs. These results also demonstrate that modification with PEG2000 can accelerate release of hydrophilic small molecule drugs from SLN.     

雷公藤内酯醇固体脂质纳米粒的制备及理化性质

目的：以聚乙二醇单硬脂酸酯表面修饰材料结合到固体脂质纳米粒（solid lipid nanoparticles,SLN）,以雷公藤内酯醇（triptolide,TPL）为模型药,制备一种具有良好亲水亲脂性的雷公藤内酯醇固体脂质纳米粒。方法：采用熔融-乳化法制备固体脂质纳米粒。通过单因素考察、中心复合设计（central composite design,CCD）,考察脂质材料、聚山梨醇酯-80和PEG-stearate（PEG-SA）三个因素对TPL-SLN粒径、包封率和载药量的影响。通过透射电镜、热分析和X-射线衍射考察TPL-SLN的理化性质,并考察其固体脂质纳米粒的稳定性以及体外释放情况。用MTT法测定其对人正常肝L02细胞和肝癌细胞HepG2的增殖抑制作用并计算其IC₅₀。结果：最优的处方：脂质材料为7.5%,聚山梨醇酯80（Tween 80）为2%和PEG-SA为2%,其粒径（193.43±6.07）nm,包封率（87.63±0.09）%,载药量（0.33±0.01）%。透射电镜观察所制备的纳米粒的形态近似于球形,DSC分析和X-射线衍射证实TPL以非晶型的形式存在于固体脂质纳米粒中。稳定性考察发现纳米粒粒径在一个月的贮存期基本没有变化（P>0.05）,体外释放表明TPL-SLN具有体外缓释特性。TPL-SLN对肿瘤细胞的抑制作用强于正常肝细胞。结论：雷公藤内酯醇聚乙二醇修饰固体脂质纳米粒有望开发为临床口服用药新剂型。     

Solid lipid nanoparticles formed by solvent-in-water emulsion-diffusion technique: development and influence on insulin stability

Insulin-loaded solid lipid nanoparticles (SLN), obtained by the solvent-in-water emulsion-diffusion technique, were produced using isovaleric acid (IVA) as organic phase, glyceryl mono-stearate (GMS) as lipid, soy lecithin and sodium taurodeoxycholate (TDC) as emulsifiers. IVA, a partially water-miscible solvent with low toxicity, was used to dissolve both insulin and lipids. SLN of spherical shape were obtained by simple water dilution of the O/W emulsion. Analysis of SLN content after processing showed interesting encapsulation efficiency with respect to therapeutic doses; moreover, insulin did not undergo any chemical modification within the nanoparticles and most of it remained stable after incubation of the SLN with trypsin solution. The biological activity of insulin, i.e. the ability to decrease glycemia in rats, was not negatively influenced by the SLN production process, as after subcutaneous administration of insulin extracted from SLN to animals, the blood glucose levels were quite similar to those obtained after administration of a conventional insulin suspension. Consequently, SLN seem to have interesting possibilities as delivery systems for oral administration of insulin.     

Solid lipid nanoparticles formed by solvent-in-water emulsion–diffusion technique: Development and influence on insulin stability

Insulin-loaded solid lipid nanoparticles (SLN), obtained by the solvent-in-water emulsion–diffusion technique, were produced using isovaleric acid (IVA) as organic phase, glyceryl mono-stearate (GMS) as lipid, soy lecithin and sodium taurodeoxycholate (TDC) as emulsifiers. IVA, a partially water-miscible solvent with low toxicity, was used to dissolve both insulin and lipids. SLN of spherical shape were obtained by simple water dilution of the O/W emulsion. Analysis of SLN content after processing showed interesting encapsulation efficiency with respect to therapeutic doses; moreover, insulin did not undergo any chemical modification within the nanoparticles and most of it remained stable after incubation of the SLN with trypsin solution. The biological activity of insulin, i.e. the ability to decrease glycemia in rats, was not negatively influenced by the SLN production process, as after subcutaneous administration of insulin extracted from SLN to animals, the blood glucose levels were quite similar to those obtained after administration of a conventional insulin suspension. Consequently, SLN seem to have interesting possibilities as delivery systems for oral administration of insulin.     

PEGylated non-ionic surfactant vesicles as drug delivery systems for Gambogenic acid

Abstract

Gambogenic acid (GNA), a popular Chinese traditional medicine, has its limitations of coming into use due to its low aqueous solubility and poor bioavailability. In this study, therefore, the PEGylated non-ionic surfactant vesicles drug delivery systems were prepared from biocompatible non-ionic surfactant of Span60, cholesterol and dicetyl phosphate (DCP) by the improved ethanol injection method, and were modified with a polyethylene glycol monostearate15 (PEG15-SA). PEG15-SA, as a biocompatible, non-toxic and non-immunogenic hydrophilic segment, was grafted onto the surface of colloidal niosomes carries to reduce the uptake by the reticuloendothelial system (RES), prolonging the circulation time and attaining higher entrapment efficiency. To our knowledge, this work is the first to report that PEG15-SA was applied to coating of niosomes for encapsulation of GNA. The optimized PEG-GNA-NISVs (P-GNA-NISVs) were characterized in terms of mean vesicles size, polydispersity index (PDI), Zeta potential and entrapment efficiency of the P-GNA-NISVs. The results showed that the mean diameter, PDI, Zeta potential, and the entrapment efficiency of the P-GNA-NISVs were 70.1?nm, 0.166, ?44.3?mV and 87.74%, respectively. Furthermore, the release studies of GNA from PEGylated niosomes in vitro and the pharmacokinetics in vivo exhibited a prolonged release profile as studied over 24?h. In conclusion, the result suggests that P-GNA-NISVs prepared in this way not only have higher encapsulation capacity, more colloidal stability but also offer an approach that the PEGylated niosomes is a promising carrier for anticancer GNA.     

Long-term stability, biocompatibility and oral delivery potential of risperidone-loaded solid lipid nanoparticles

A solid lipid nanoparticles (SLN) formulation to improve the oral delivery of risperidone (RISP), a poorly water-soluble drug, was designed and tested. Initially, lipid-RISP solubility was screened to select the best lipid for SLN preparation. Compritol(?)-based formulations were chosen and their long-term stability was assessed over two years of storage (at 25°C and 4°C) by means of particle size, polydispersity index (PI), zeta potential (ZP) and encapsulation efficiency (EE) measurements. SLN shape was observed by transmission electron microscopy (TEM) at the beginning and end of the study. The oxidative potential (OP) of the SLN was measured and their biocompatibility with Caco-2 cells was evaluated using the (4,5-dimethylthiazol-2-yl)2,5-dyphenyl-tetrazolium bromide (MTT) assay. In vitro drug release and transport studies were performed to predict the in vivo release profile and to evaluate the drug delivery potential of the SLN formulations, respectively. The RISP-loaded SLN systems were stable and had high EE and similar shape to the placebo formulations before and after storage. Classical Fickian diffusion was identified as the release mechanism for RISP from the SLN formulation. Biocompatibility and dose-dependent RISP transport across Caco-2 cells were observed for the prepared SLN formulations. The viability of SLN as formulations for oral delivery of poorly water-soluble drugs such as RISP was illustrated.     

Double-coated poly (butylcynanoacrylate) nanoparticulate delivery systems for brain targeting of dalargin via oral administration

The aim of this study is to evaluate oral administration of poly (butylcyanoacrylate) nanoparticulate delivery systems (PBCA-NDSs), double-coated with Tween 80 and poly (ethylene) glycol (PEG) 20000 for brain delivery of hexapeptide dalargin, an anti-nociceptive peptide that does not cross blood-brain barrier (BBB) by itself. Studies have proven the brain uptake of Tween 80 overcoated nanoparticles after intravenous administration, but studies for brain delivery of nanoparticles after oral administration had been limited due to reduced bioavailability of nanoparticles and extensive degradation of the peptide and/or nanoparticles by gastrointestinal enzymes. To address this problem, dalargin-loaded PBCA-NDS were successively double-coated with Tween 80 and PEG 20000 in varied concentrations of up to 2% each. Measurement of in vivo central anti-nociceptive effect of dalargin along with a dose response curve was obtained by the tail flick test following the oral administration of PBCA-NDSs to mice. Results from the tail flick test indicated that significant dalargin-induced analgesia was observed from PBCA-NDSs with double-coating of Tween and PEG in comparison with single-coating of either Tween or PEG. Hence, it could be concluded that surface coated PBCA-NDS can be used successfully for brain targeting of dalargin or other peptides administered orally. However, further studies are required to elucidate the exact transport mechanism of PBCA-NDSs from gastrointestinal tract to brain.     

Novel galactosylated SLN for hepatocyte-selective targeting of floxuridinyl diacetate

This paper describes the preparation and liver-targeting traits of new solid lipid nanoparticles (SLN) containing floxuridinyl diacetate (FUDRA) modified with beta-d-galactosides (Gn). FUDRA and Gn were incorporated, respectively, to study the drug loading (DL), drug release, and in vivo distribution property. Transmission electron microscopy analysis revealed that the particle sizes of FUDRA-SLN, FUDRA-G2SLN and FUDRA-G10SLN were 215.3, 91.3 and 106.0 nm, with DLs of 8.20, 8.37 and 8.91%, respectively. In an in vivo study of Specific pathogen-free mice, the complexes were administered via the tail vein. Judging on the basis of 5-fluoro-2'-deoxyuridinum (FUDR) concentration in blood and viscera with HPLC analysis, FUDRA release was confirmed and a significant enrichment of SLN modified with Gn was observed in the liver with Gn complex (targeting rates of SLN-G2 and SLN-G10 are 11.25 and 11.43 for the liver, respectively) in comparison with FUDR-sol (targeting rate is 1.71). In mice, FUDR could be detected in the liver at 40, 160, 320 and 480 min after i.v. administration of FUDR-sol, FUDRA-SLN, FUDRA-G2SLN and FUDRA-G10SLN, respectively. These results suggest that G2 and G10 are ideal materials for preparing active liver targeting SLN. FUDRA-G2SLN and, particularly, FUDRA-G10SLN have desirable hepatocyte-selective targeting and sustained-release action in healthy mice.