新型纳米粒给药系统——纳米结构的脂质载体

固体脂质纳米粒（SLN）已被公认是一种新型的纳米粒给药系统，但SLN有不同程度的潜在问题。作为新一代的纳米粒给药系统——纳米结构的脂质载体（Nanostructured lipid carriers，NLC）可减小或者避免SLN有限载药能力及储藏过程包封药物泄漏的问题，而且能调整SLN的释放曲线。NLC以固体脂质与物态上相异的液体脂质混合制备得到，形成3种类型特殊结构的脂质骨架：结晶不完全态、无定形态、复合态。现介绍一种特殊的制备方法，不仅适合于制备NLC，而且也可作为制备高粒子浓度（30％～95％）SLN分散液的方法。描述了NLC作为给药系统潜在的应用前景。     

固体脂质纳米粒和纳米结构脂质载体在药物传递中的研究进展

基于固体脂质的纳米粒（Solid lipid - based nanoparticles,SLBNs）作为新型药物传递系统比常规的药物传递系统存在优势。通常,基于固体脂质的纳米粒可以分成两种形态,即固体脂质纳米粒（ Solid lipid nanoparticles, SLNs）和纳米结构脂质载体（Nanostructured lipid carriers,NLCs）。但固体脂质纳米粒与纳米结构脂质载体在基质的组成上不同,本文就基于固体脂质的纳米粒的制备技术、表征方法及应用的最新研究进展进行总结,为基于固体脂质的纳米粒进一步研究提供参考依据。     

单唾液酸四己糖神经节苷脂固体脂质纳米粒的制备方法及性质考查

目的：建立适用于生产的单唾液酸四己糖神经节苷脂（GM1）固体脂质纳米粒的制备方法。方法：分别采用溶剂乳化法和高压乳匀法制备GM1固体脂质纳米粒,并将制备结果进行比较。结果：通过比较两种制备方法制得的GM1固体脂质纳米粒进行外观及稳定性、形态学考查、包封率等指标,同时比较以该固体脂质纳米粒制备的冻干粉针剂性状,发现高压乳匀法获得的固体脂质纳米粒性质较佳。结论：高压乳匀法可作为实际GM1固体脂质纳米粒冻干粉针剂中间体的制备方法。     

蓝萼甲素固体脂质纳米粒的制备工艺研究

目的以固体脂质纳米粒作为蓝萼甲素新型缓释给药系统,进行蓝萼甲素固体脂质纳米粒的制备工艺研究。方法采用乳化蒸发-低温固化法,均匀设计优化处方,按照优化工艺条件,以硬脂酸作为蓝萼甲素模型药物载体,制备得到蓝萼甲素固体脂质纳米粒,并对其包封率进行考察。结果本研究制得的蓝萼甲素固体脂质纳米粒的包封率达到80.4%。结论本研究方法可以作为蓝萼甲素固体脂质纳米粒的制备方法。     

甘草次酸固体脂质纳米凝胶的制备及体外透皮效应

目的制备甘草次酸固体脂质纳米凝胶并考察其体外透皮效应。方法采用微乳液法制备甘草次酸固体脂质纳米粒并考察其包封率、粒径与表面电位,以研和法制备固体脂质纳米粒凝胶;采用改良Franz立式扩散池法进行体外透皮实验,HPLC法测定甘草次酸含量,评价甘草次酸固体脂质纳米粒凝胶的经皮渗透结果。结果甘草次酸固体脂质纳米粒外观为圆球形或椭球形;甘草次酸固体脂质纳米粒的包封率为64.75%±1.36%,粒径范围(46.13±20.10)nm,电位分布范围为(-53.4±7.11)mV。24h甘草次酸固体脂质纳米粒凝胶较甘草次酸固体脂质纳米粒的累积透过量提高66%。结论甘草次酸固体脂质纳米粒凝胶能提高甘草次酸的透皮速率,有望成为甘草次酸透皮给药的新型制剂。     

溶剂扩散法制备丙酸倍氯米松固体脂质纳米粒

目的　建立一种高效的固体脂质纳米粒制备与分离方法。方法　用水性溶剂扩散法 ,制备得到甘油单硬脂酸酯固体脂质纳米粒。通过调节纳米粒表面Zeta电位 ,提高纳米粒的回收率。结果　用水性溶剂扩散法可以简便、快速制备得到含药固体脂质纳米粒 ,低转速离心 (40 0 0r·min- 1 )即可达到纳米粒与分散体系之间的分离 ,回收率明显高于未调节纳米粒表面Zeta电位条件下的高速离心分离方法。用本法制备得到的纳米粒在最初 3h有药物的突释现象 ,随后 4d药物的释放明显缓慢 ,每天释放约药物总量的 6%。结论　水性溶剂扩散法适用于固体脂质纳米粒的制备 ,得到的固体脂质纳米粒可实现药物的控制释放     

依托泊苷固体脂质纳米粒的制备与抗癌活性研究

摘 要 目的：制备依托泊苷固体脂质纳米粒,并评价其对小鼠接种Lewis肺癌细胞的抑瘤率。方法: 采用热熔乳化 高压均质法制备依托泊苷固体脂质纳米粒,考察依托泊苷固体脂质纳米粒的外观、微观结构、粒径分布、Zeta电位等理化性质,评价依托泊苷固体脂质纳米粒体外释药行为,比较依托泊苷固体脂质纳米粒与依托泊苷注射液对小鼠接种Lewis肺癌细胞的抑制效果。结果:本研究制备的依托泊苷固体脂质纳米粒外观呈淡蓝色透明状液体,在透射电镜观察呈圆整球状或类球状分布,大小较为均匀;平均粒径为（153.2±32.8）nm,PdI为（0.185±0.031）,Zeta电位为（-17.4±1.1）mV;依托泊苷固体脂质纳米粒可延缓药物释放,在24 h内药物累积释放52.4%;依托泊苷固体脂质纳米粒的抑瘤率显著高于依托泊苷注射液（P<0.05）,说明依托泊苷固体脂质纳米粒能够显著抑制Lewis肺癌细胞在小鼠体内生长。结论:本研究通过热熔乳化 高压均质法制备的依托泊苷固体脂质纳米粒对Lewis肺癌细胞具有良好的抑瘤效果,可以作为依托泊苷的新型给药系统,对肺癌治疗具有一定的应用前景。     

溶剂扩散法制备丙酸倍氯米松固体脂质纳米粒溶剂扩散法制备丙酸倍氯米松固体脂质纳米粒

目的 建立一种高效的固体脂质纳米粒制备与分离方法。方法 用水性溶剂扩散法,制备得到甘油单硬脂酸酯固体脂质纳米粒。通过调节纳米粒表面Zeta电位,提高纳米粒的回收率。结果 用水性溶剂扩散法可以简便、快速制备得到含药固体脂质纳米粒,低转速离心(4 000 r·min^-1)即可达到纳米粒与分散体系之间的分离,回收率明显高于未调节纳米粒表面Zeta电位条件下的高速离心分离方法。用本法制备得到的纳米粒在最初3 h有药物的突释现象,随后4 d药物的释放明显缓慢,每天释放约药物总量的6%。结论 水性溶剂扩散法适用于固体脂质纳米粒的制备,得到的固体脂质纳米粒可实现药物的控制释放。     

固体脂质纳米粒制备及应用研究进展

目的综述固体脂质纳米粒制备及应用进展。方法以国内外有代表性的文献和资料为依据,将固体脂质纳米粒的制备及应用等情况进行了分析与归纳。结果固体脂质纳米粒的多种制备方法各有优、缺点,其中以高压乳匀法和微乳法被推崇。调整制备参数可调整药物的包封率和释药曲线。结论固体脂质纳米粒是一种性能优异、有发展前景的新型给药系统。     

不同工艺制备的固体脂质纳米粒系统性能比较研究

目的：比较不同工艺制备的固体脂质纳米粒系统性能。方法：分别采用长时间高剪切法、长时间探头超声法、单次高剪切超声法和改进的高剪切超声法制备固体脂质纳米粒混悬液，应用激光粒度仪分析仪测定纳米粒粒径及其分布特征，据此评价4种方法制备的固体脂质纳米粒系统性能。结果：与其他3种制备方法比较，改进的高剪切超声法制备的固体脂质纳米粒混悬液粒径分布窄，且呈单模分布，平均粒径约100nm，具良好的贮存稳定性，4℃下可稳定放置达半年。结论：改进的高剪切超声法可制备出性能优良的稳定的固体脂质纳米粒系统。     

Solid Lipid Nanoparticles (SLN) and Oil-Loaded SLN Studied by Spectrofluorometry and Raman Spectroscopy

Purpose Recently, colloidal dispersions made of mixtures from solid and liquid lipids have been described to overcome the poor drug loading capacity of solid lipid nanoparticles (SLN). It has been proposed that these nanostructured lipid carriers (NLC) are composed of oily droplets, which are embedded in a solid lipid matrix. High loading capacities and controlled release characteristics have been claimed. It is the objective of the present paper to investigate these new NLC particles in more detail to obtain insights into their structure. Methods Colloidal lipid dispersions were produced by high-pressure homogenization. Particle sizes were estimated by laser diffraction and photon correlation spectroscopy. The hydrophobic fluorescent marker nile red (NR) was used as model drug, and by fluorometric spectroscopy, the molecular environment (polarity) was elucidated because of solvatochromism of NR. The packaging of the lipid nanoparticles was investigated by Raman spectroscopy and by densimetry. The light propagation in lipid nanodispersions was examined by refractometry to obtain further insights into the nanostructural compositions of the carriers. Results Fluorometric spectroscopy clearly demonstrates that NLC nanoparticles offer two nanocompartments of different polarity to accommodate NR. Nevertheless, in both compartments, NR experiences less protection from the outer water phase than in a nanoemulsion. In conventional SLN, lipid crystallization leads to the expulsion of the lipophilic NR from the solid lipid. Measurements performed by densimetry and Raman spectroscopy confirm the idea of intact glyceryl behenate lattices in spite of oil loading. The lipid crystals are not disturbed in their structure as it could be suggested in case of oil incorporation. Refractometric data reveal the idea of light protection because of incorporation of sensitive drug molecules in NLC. Conclusion Neither SLN nor NLC lipid nanoparticles did show any advantage with respect to incorporation rate compared to conventional nanoemulsions. The experimental data let us conclude that NLC lipid nanoparticles are not spherical solid lipid particles with embedded liquid droplets, but they are rather solid platelets with oil present between the solid platelet and the surfactant layer.     

Nanostructured lipid carriers (NLC) in cosmetic dermal products

The first generation of lipid nanoparticles was introduced as solid lipid nanoparticles (SLN), the second, improved generation as nanostructured lipid carriers (NLC). Identical to the liposomes, the lipid nanoparticles (NLC) appeared as products first on the cosmetic market. The article gives an overview of the cosmetic benefits of lipid nanoparticles, that means enhancement of chemical stability of actives, film formation, controlled occlusion, skin hydration, enhanced skin bioavailability and physical stability of the lipid nanoparticles as topical formulations. NLC are on the market as concentrates to be used as cosmetic excipients, special formulation challenges for these products are discussed. NLC appeared also in a number of finished cosmetic products world-wide. An overview of these products is provided including their special effects due to the lipid nanoparticles, lipids used for their production and incorporated cosmetic actives.     

Characterization of indomethacin-loaded lipid nanoparticles by differential scanning calorimetry

Solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC) are interesting nanoparticulate delivery systems produced from solid lipids. Both carrier types are submicron size particles but they can be distinguished by their inner structure. In the present paper, indomethacin (IND)-loaded SLN and NLC were prepared and the organization and distribution of the different ingredients originating each type of nanoparticle system were studied by differential scanning calorimetry (DSC) technique. Furthermore, mean particle size and percentage of drug encapsulation were also determined. From the results obtained, NLC lipid organization guaranteed an increased indomethacin encapsulation in comparison with SLN. DSC static and dynamic measurements performed on SLN and NLC showed that oil nanocompartments incorporated into NLC solid matrix drastically influenced drug distribution inside the nanoparticle system. Controlled release from NLC system could be explained considering both drug partition between oil nanocompartments and solid lipid and a successive partition between solid lipid and water.     

Preparation and characteristics of monostearin nanostructured lipid carriers

Nanostuctured lipid carriers (NLC) consisted of solid lipid and liquid lipid are a new type of lipid nanoparticles, which offer the advantage of improved drug loading capacity and release properties. In this study, solvent diffusion method was employed to produce NLC. Monostearin (MS) and caprylic/capric triglycerides (CT) were chosen as the solid lipid and liquid lipid. Clobetasol propionate used as a model drug was incorporated into the NLC. The influences of preparation temperature and CT content on physicochemical properties of the NLC were characterized. As a result, monostearin solid lipid nanoparticles (without CT content, SLN) obtained at higher temperature (70 degrees C) exhibited slightly higher drug loading capacity than that of 0 degrees C (P < 0.05). In contrast, the production temperature made little effect on NLC drug loading capacity (P > 0.05). The improved drug loading capacity was observed for NLC and it enhanced with increasing the CT content in NLC. The results were explained by differential scanning calorimetry (DSC) measurement for NLC. The incorporation of CT to NLC led to crystal order disturbance and thus left more space to accommodate drug molecules. NLC displayed a good ability to reduce the drug expulsion in storage compared to SLN. The in vitro release behaviors of NLC were dependent on the production temperature and CT content. NLC obtained at 70 degrees C exhibited biphasic drug release pattern with burst release at the initial 8h and prolonged release afterwards, whereas NLC obtained at 0 degrees C showed basically sustained drug release throughout the release time. The drug release rates were increased with increasing the CT content. These results indicated that the NLC produced by solvent diffusion method could potentially be exploited as a carrier with improved drug loading capacity and controlled drug release.     

Preparation, characterization and physico-chemical properties of solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC): their benefits as colloidal drug carrier systems

Solid lipid nanoparticles (SLN) have attracted increasing attention by various research groups and companies since the early 1990s. Their advantages over existing traditional carriers have been clearly documented. In addition, modified SLN have been described which are nanostructured lipid carriers (NLC) composed of liquid lipid blended with a solid lipid to form a nanostructured solid particle matrix. NLC combine controlled release characteristics with some advantages over SLN. This paper reviews the production techniques, characterization and physical stability of these systems including destabilizing factors and principles of drug loading, then considers aspects and benefits of SLN and NLC as colloidal drug carriers.     

Lipid nanoparticles (SLN, NLC) in cosmetic and pharmaceutical dermal products

Solid lipid nanoparticles (SLN) are distinguishable from nanostructured lipid carriers (NLC) by the composition of the solid particle matrix. Both are an alternative carrier system to liposomes and emulsions. This review paper focuses on lipid nanoparticles for dermal application. Production of lipid nanoparticles and final products containing lipid nanoparticles is feasible by well-established production methods. SLN and NLC exhibit many features for dermal application of cosmetics and pharmaceutics, i.e. controlled release of actives, drug targeting, occlusion and associated with it penetration enhancement and increase of skin hydration. Due to the production of lipid nanoparticles from physiological and/or biodegradable lipids, this carrier system exhibits an excellent tolerability. The lipid nanoparticles are a "nanosafe" carrier. Furthermore, an overview of the cosmetic products currently on the market is given and the improvement of the benefit/risk ratio of the topical therapy is shown.     

Lipid nanoparticles as carrier for octyl-methoxycinnamate: in vitro percutaneous absorption and photostability studies

The aim of the present study was the evaluation of lipid nanoparticles (solid lipid nanoparticles, SLN, and nanostructured lipid carriers, NLC) as potential carriers for octyl-methoxycinnamate (OMC). The release pattern of OMC from SLN and NLC was evaluated in vitro, determining its percutaneous absorption through excised human skin. Additional in vitro studies were performed in order to evaluate, after UVA radiation treatment, the spectral stability of OMC-loaded lipid nanoparticles. From the obtained results, ultrasonication method yielded both SLN and NLC in the nanometer range with a high active loading and a particle shape close to spherical. Differential scanning calorimetry data pointed out the key role of the inner oil phase of NLC in stabilizing the particle architecture and in increasing the solubility of OMC as compared with SLN. In vitro results showed that OMC, when incorporated in viscosized NLC dispersions (OMC-NLC), exhibited a lower flux with respect to viscosized SLN dispersions (OMC-SLN) and two reference formulations: a microemulsion (OMC-ME) and a hydroalcoholic gel (OMC-GEL). Photostability studies revealed that viscosized NLC dispersions were the most efficient at preserving OMC from ultraviolet-mediated photodegradation.     

Solid lipid nanoparticles for parenteral drug delivery

This review describes the use of nanoparticles based on solid lipids for the parenteral application of drugs. Firstly, different types of nanoparticles based on solid lipids such as "solid lipid nanoparticles" (SLN), "nanostructured lipid carriers" (NLC) and "lipid drug conjugate" (LDC) nanoparticles are introduced and structural differences are pointed out. Different production methods including the suitability for large scale production are described. Stability issues and drug incorporation mechanisms into the particles are discussed. In the second part, the biological activity of parenterally applied SLN and biopharmaceutical aspects such as pharmacokinetic profiles as well as toxicity aspects are reviewed.     

Physicochemical characterization and in vitro release studies of ascorbyl palmitate-loaded semi-solid nanostructured lipid carriers (NLC gels)

The aim of this study was to characterize the physicochemical properties and to study in vitro release of ascorbyl palmitate from semi-solid lipid nanoparticles based on nanostructured lipid carriers (NLC gels) systems with the desired viscosity for dermal delivery. NLC gels were obtained by a one-step production procedure employing a high pressure homogenization technique using different solid lipid matrices. Ascorbyl palmitate (AP) was selected as a lipophilic active ingredient due to its range of cosmetic applications. After the production, particles within the size range 170-250 nm having polydispersity index lower than 0.3 were obtained from all formulations. After the AP incorporation into the NLC gels, the zeta potential increased to values higher than |30 mV|. Almost 100% encapsulation efficiency was observed. The obtained SEM and AFM data revealed non-spherical shaped nanoparticles. From DSC and X-ray diffraction studies, it was shown that the lipid recrystallized in the solid state possessing a less ordered structure as compared to the bulk material. The release study of active-loaded NLC gel formulations using Franz diffusion cells revealed that the type of lipid matrix affects both the rate and the release pattern. The viscoelastic measurements revealed a more elastic than viscous behaviour of NLC formulations indicating a typical gel-like structure.     

新型纳米结构脂质载体系统的研究进展

目的介绍新型的纳米结构脂质载体系统的研究进展,为其研究和应用提供参考。方法查阅相关文献33篇,进行整理和归纳。结果新型的纳米结构脂质载体能够克服固体脂质纳米粒的一些不足,并具有独特的结构特征,药物的包封机理和释放特征。结论纳米结构脂质载体作为药物传递系统的一种新剂型,具有广阔的发展前景。