固体脂质纳米粒制备方法的研究进展

固体脂质纳米粒是近年来备受关注的一种新型给药系统,本文对近年来固体脂质纳米粒的新型制备方法:薄膜接触器法、超声-挤压过滤法、微通道法、纳米反应嚣法的制备原理,方法及特点进行了讨论,并对现阶段存在的问题及今后的研究方向进行了展望.     

凝聚法制备川芎嗪固体脂质纳米粒

目的:制备川芎嗪固体脂质纳米粒.方法:采用凝聚法制备,并以包封率和载药量为指标采用正交设计法优化川芎嗪固体脂质纳米粒的制备工艺,并利用透射电镜、激光粒度分析仪、Zeta电位测定仪表征了其药剂学性质结果:所得川芎嗪固体脂质纳米粒的最佳制备处方是川芎嗪45mg,卵磷脂600mg,硬脂酸450mg,0.4%的泊洛沙姆60ml 结论:该处方可用于川芎嗪固体脂质纳米粒的制备,工艺简单、可行.     

固体脂质纳米粒的制备及应用研究进展

固体脂质纳米粒自1991年出现以来引起了广泛的关注,它综合了传统胶体给药系统如乳剂、脂质体及聚合物纳米粒等的优点,同时避免了它们的许多缺点。本文综述了纳米粒的制备方法及适合工业大生产的方法,介绍了固体脂质纳米粒的理化性质及其研究方法,并讨论了适合于固体脂质纳米粒的不同的给药途径。     

壳聚糖和帕米膦酸双修饰的固体脂质纳米粒的制备

目的:制备壳聚糖和帕米膦酸双修饰的固体脂质纳米粒。方法:首先利用课题组发表的专利合成帕米膦酸修饰Brij78的新型非离子表面活性剂(Pa-Brij78),然后以壳聚糖(CS)溶液为水相,Pa-Brij78为乳化剂,E-Wax为油相,采用微乳法,利用修饰的帕米膦酸基团与壳聚糖分子链中质子化的氨基交联反应原理,通过一系列实验条件的探索,确定了最佳实验工艺条件,成功制备了壳聚糖和帕米膦酸双修饰的固体脂质纳米粒。通过动态光散射(DLS)粒径仪测定了纳米粒的粒径大小和Zeta电位;透射电子显微镜(TEM)对CS-Pa-Brij78-SLNs的形貌结构进行了表征。结果:实验结果显示,制备壳聚糖和帕米膦酸双修饰的固体脂质纳米粒的最佳条件为:p H=6.0,壳聚糖浓度分别为0.1%,0.2%;反应温度65℃,反应时间40 min,在该条件下,制备的壳聚糖和帕米膦酸双修饰的固体脂质纳米粒(CS-Pa-Brij78-SLNs)粒径分别为97.9±6.6 nm和182.4±62.2 nm,表面电位分别为(+5.21±1.4m V);(+7.94±0.80 m V),装载姜黄素时,载药量为10%,包封率在90%以上,透射电镜下观察其形态圆整,清晰可见壳聚糖包裹的电晕。结论:本文以壳聚糖(CS)溶液为水相,合成的新型非离子表面活性剂Pa-Brij78为乳化剂,E-Wax为油相,采用微乳化法,经过最佳实验条件的探索,通过一步法成功制备了稳定的壳聚糖和帕米膦酸双修饰的固体脂质纳米粒(CS-Pa-Brij78-SLNs)。     

Preparation and Characterization of Fenofibrate-Loaded Nanostructured Lipid Carriers for Oral Bioavailability Enhancement

The aim of this study is to investigate the potential of nanostructured lipid carriers (NLCs) in improving the oral bioavailability of a lipid lowering agent, fenofibrate (FEN). FEN-loaded NLCs (FEN-NLCs) were prepared by hot homogenization followed by an ultrasonication method using Compritol 888 ATO as a solid lipid, Labrafil M 1944CS as a liquid lipid, and soya lecithin and Tween 80 as emulsifiers. NLCs were characterized in terms of particle size and zeta pote\ntial, surface morphology, encapsulation efficiency, and physical state properties. Bioavailability studies were carried out in rats by oral administration of FEN-NLC. NLCs exhibited a spherical shape with a small particle size (84.9 ± 4.9 nm). The drug entrapment efficiency was 99% with a loading capacity of 9.93 ± 0.01% (w/w). Biphasic drug release manner with a burst release initially, followed by prolonged release was depicted for in vitro drug release studies. After oral administration of the FEN-NLC, drug concentration in plasma and AUC_t-∞ was fourfold higher, respectively, compared to the free FEN suspension. According to these results, FEN-NLC could be a potential delivery system for improvement of loading capacity and control of drug release, thus prolonging drug action time in the body and enhancing the bioavailability.KEY WORDS: bioavailability, fenofibrate, nanoparticles, nanostructured lipid carriers     

固体脂质纳米粒的制备及在治疗中的应用研究

固体脂质纳米粒(SLN)是20世纪90年代发展起来的一种性能优异的新型纳米粒给药剂型作为一种新型载体,可有效提高包封药物的稳定性、提高病变部位靶向性、低毒性与组织亲和性,为药物的体内递送提供了一种新的方法。本文主要针对固体脂质纳米粒的制备,发展现状,目前存在的问题及解决思路等作以介绍与总结。并在此基础上,介绍了新的脂质纳米粒,纳米脂质载体(nanostructured lipid carriers,NLC)和药脂结合物纳米粒(Lipid drug conjugate nanoparticles,LDC),以及未来固体脂质纳米粒的发展方向。     

Modulating Drug Release and Enhancing the Oral Bioavailability of Torcetrapib with Solid Lipid Dispersion Formulations

The development of drug dispersions using solid lipids is a novel formulation strategy that can help address the challenges of poor drug solubility and systemic exposure after oral administration. The highly lipophilic and poorly water-soluble drug torcetrapib could be effectively formulated into solid lipid microparticles (SLMs) using an anti-solvent precipitation strategy. Acoustic milling was subsequently used to obtain solid lipid nanoparticles (SLNs). Torcetrapib was successfully incorporated into the lipid matrix in an amorphous state. Spherical SLMs with mean particle size of approximately 15–18 μm were produced with high drug encapsulation efficiency (>96%) while SLNs were produced with a mean particle size of 155 nm and excellent colloidal stability. The in vitro drug release and the in vivo absorption of the solid lipid micro- and nanoparticles after oral dosing in rats were evaluated against conventional crystalline drug powders as well as a spray dried amorphous polymer dispersion formulation. Interestingly, the in vitro drug release rate from the lipid particles could be tuned for immediate or extended release by controlling either the particle size or the precipitation temperature used when forming the drug-lipid particles. This change in the rate of drug release was manifested in vivo with changes in Tmax as well. In addition, in vivo pharmacokinetic studies revealed a significant increase (∼6 to 11-fold) in oral bioavailability in rats dosed with the SLMs and SLNs compared to conventional drug powders. Importantly, this formulation approach can be performed rapidly on a small scale, making it ideal as a formulation technology for use early in the drug discovery timeframe.Electronic supplementary materialThe online version of this article (doi:10.1208/s12249-015-0299-8) contains supplementary material, which is available to authorized users.KEY WORDS: anti-solvent precipitation, controlled release, formulation, nanoparticles, solid lipid     

Preparation and Evaluation of Miconazole Nitrate-Loaded Solid Lipid Nanoparticles for Topical Delivery

The purpose of this study was to prepare miconazole nitrate (MN) loaded solid lipid nanoparticles (MN-SLN) effective for topical delivery of miconazole nitrate. Compritol 888 ATO as lipid, propylene glycol (PG) to increase drug solubility in lipid, tween 80, and glyceryl monostearate were used as the surfactants to stabilize SLN dispersion in the SLN preparation using hot homogenization method. SLN dispersions exhibited average size between 244 and 766 nm. All the dispersions had high entrapment efficiency ranging from 80% to 100%. The MN-SLN dispersion which showed good stability for a period of 1 month was selected. This MN-SLN was characterized for particle size, entrapment efficiency, and X-ray diffraction. The penetration of miconazole nitrate from the gel formulated using selected MN-SLN dispersion as into cadaver skins was evaluated ex-vivo using franz diffusion cell. The results of differential scanning calorimetry (DSC) showed that MN was dispersed in SLN in an amorphous state. The MN-SLN formulations could significantly increase the accumulative uptake of MN in skin over the marketed gel and showed a significantly enhanced skin targeting effect. These results indicate that the studied MN-SLN formulation with skin targeting may be a promising carrier for topical delivery of miconazole nitrate.     

Enhanced Oral Bioavailability of Griseofulvin via Niosomes

The aim of the present report was to develop nonionic surfactant vesicles (niosomes) to improve poor and variable oral bioavailability of griseofulvin. Niosomes were prepared by using different nonionic surfactants span 20, span 40, and span 60. The lipid mixture consisted of surfactant, cholesterol, and dicetyl phosphate in the molar ratio of 125:25:1.5, 100:50:1.5, and 75:75:1.5, respectively. The niosomal formulations were prepared by thin film method and ether injection method. The influence of different formulation variables such as surfactant type, surfactant concentration, and cholesterol concentration was optimized for size distribution and entrapment efficiency for both methods. Result indicated that the niosomes prepared by thin film method with span 60 provided higher entrapment efficiency. The niosomal formulation exhibited significantly retarded in vitro release as compared with free drug. The in vivo study revealed that the niosomal dispersion significantly improved the oral bioavailability of griseofulvin in albino rats after a single oral dose. The maximum concentration (C _max) achieved in case of niosomal formulation was approximately double (2.98 μg/ml) as compared to free drug (1.54 μg/ml). Plasma drug profile also suggested that the developed niosomal system also has the potential of maintaining therapeutic level of griseofulvin for a longer period of time as compared to free griseofulvin. The niosomal formulation showed significant increase in area under the curve_0-24 (AUC; 41.56 μg/ml h) as compared to free griseofulvin (22.36 μg/ml h) reflecting sustained release characteristics. In conclusion, the niosomal formulation could be one of the promising delivery system for griseofulvin with improved oral bioavailability and prolonged drug release profiles.     

Diazepam-Loaded Solid Lipid Nanoparticles: Design and Characterization

The aim of the present study was to investigate the feasibility of the inclusion of a water-insoluble drug (diazepam, DZ) into solid lipid nanoparticles (SLNs), which offer combined advantages of rapid onset and prolonged release of the drug. This work also describes a new approach to prepare suppositories containing DZ-loaded SLN dispersions, as potential drug carrier for the rectal route. Modified high-shear homogenization and ultrasound techniques were employed to prepare SLNs. The effect of incorporation of different concentrations of Compritol® ATO 888 or Imwitor® 900K and Poloxamer 188 or Tween 80 was investigated. Results showed that varying the type or concentration of lipid matrix or surfactant had a noticeable influence on the entrapment efficiencies, particle size, and release profiles of prepared SLNs. Differential scanning calorimetry and X-ray diffraction measurements showed that the majority of SLNs possessed less ordered arrangements of crystals than the corresponding bulk lipids, which was favorable for increasing the drug loading capacity. Transmission electron microscopy and laser diffractometry studies revealed that the prepared nanoparticles were round and homogeneous and 60% of the formulations were less than 500 nm. Additionally, SLN formulations showed significant (P?in vitro release of DZ from the suppositories prepared using DZ-loaded SLN dispersions (equivalent to 2 mg DZ) was significantly (P?相似文献   

Physical-Chemical Characterization and Formulation Considerations for Solid Lipid Nanoparticles

Pure glyceryl mono-oleate (GMO) (lipid) and different batches of GMO commonly used for the preparation of GMO-chitosan nanoparticles were characterized by modulated differential scanning calorimetry (MDSC), cryo-microscopy, and cryo-X-ray powder diffraction techniques. GMO-chitosan nanoparticles containing poloxamer 407 as a stabilizer in the absence and presence of polymers as crystallization inhibitors were prepared by ultrasonication. The effect of polymers (polyvinyl pyrrolidone (PVP), Eudragits, hydroxyl propyl methyl cellulose (HPMC), polyethylene glycol (PEG)), surfactants (poloxamer), and oils (mineral oil and olive oil) on the crystallization of GMO was investigated. GMO showed an exothermic peak at around ?10°C while cooling and another exothermic peak at around ?12°C while heating. It was followed by two endothermic peaks between 15 and 30 C, indicative of GMO melting. The results are corroborated by cryo-microscopy and cryo-X-ray. Significant differences in exothermic and endothermic transition were observed between different grades of GMO and pure GMO. GMO-chitosan nanoparticles resulted in a significant increase in particle size after lyophilization. MDSC confirmed that nanoparticles showed similar exothermic crystallization behavior of lipid GMO. MDSC experiments showed that PVP inhibits GMO crystallization and addition of PVP showed no significant increase in particle size of solid lipid nanoparticle (SLN) during lyophilization. The research highlights the importance of extensive physical-chemical characterization for successful formulation of SLN.     

Paliperidone-Loaded Nanolipomer System for Sustained Delivery and Enhanced Intestinal Permeation: Superiority to Polymeric and Solid Lipid Nanoparticles

Paliperidone (PPD) is the most recent second-generation atypical antipsychotic approved for the treatment of schizophrenia. An immediate release dose causes extrapyramidal side effects. In this work, a novel nanolipomer carrier system for PPD with enhanced intestinal permeability and sustained release properties has been developed and optimized. PPD was successfully encapsulated into a lipomer consisting of a specific combination of biocompatible materials including poly-ε-caprolactone as a polymeric core, Lipoid S75, and Gelucire® 50/13 as a lipid shell and polyvinyl alcohol as a stabilizing agent. The lipomer system was characterized by dynamic light scattering, TEM, DSC, and FTIR. An optimized lipomer formulation possessed a particle size of 168 nm, PDI of 0.2, zeta potential of ?23 mV and an encapsulation efficiency of 87.27%?±?0.098. Stability in simulated gastrointestinal fluids investigated in terms of particle size, zeta potential, and encapsulation efficiency measurements ensured the integrity of the nanoparticles upon oral administration. PPD-loaded nanolipomers demonstrated a superior sustained release behavior up to 24 h and better ex vivo intestinal permeation for PPD compared to the corresponding polymeric and solid lipid nanoparticles and drug suspension. The in vitro hemocompatibility test on red blood cells revealed no hemolytic effect of PPD-loaded lipomers which reflects its safety. The elaborated nanohybrid carrier system represents a promising candidate for enhancing the absorption of PPD providing a 2.6-fold increase in the intestinal permeation flux compared to the drug suspension while maintaining a sustained release behavior. It is a convenient alternative to the commercially available dosage form of PPD.     

Lipid Effects on Expulsion Rate of Amphotericin B from Solid Lipid Nanoparticles

We aimed to investigate the effects that natural lipids, theobroma oil (TO) and beeswax (BW), might have on the physical properties of formulated nanoparticles and also the degree of expulsion of encapsulated amphotericin B (AmB) from the nanoparticles during storage. Lecithin and sodium cholate were used as emulsifiers whilst oleic acid (OA) was used to study the influence of the state of orderliness/disorderliness within the matrices of the nanoparticles on the degree of AmB expulsion during storage. BW was found to effect larger z-average diameter compared with TO. Lecithin was found to augment the stability of the nanoparticles imparted by BW and TO during storage. An encapsulation efficiency (%EE) of 59% was recorded when TO was the sole lipid as against 42% from BW. In combination however, the %EE dropped to 39%. When used as sole lipid, TO or BW formed nanoparticles with comparatively higher enthalpies, 21.1 and 23.3 J/g respectively, which subsequently caused significantly higher degree of AmB expulsion, 81 and 83% respectively, whilst only 11.8% was expelled from a binary TO/BW mixture. A tertiary TO/BW/OA mixture registered the lowest enthalpy at 8.07 J/g and expelled 12.6% of AmB but encapsulated only 22% of AmB. In conclusion, nanoparticles made from equal concentrations of TO and BW produced the most desirable properties and worthy of further investigations.     

Mixed Polyethylene Glycol-Modified Breviscapine-Loaded Solid Lipid Nanoparticles for Improved Brain Bioavailability: Preparation,Characterization, and In Vivo Cerebral Microdialysis Evaluation in Adult Sprague Dawley Rats

Breviscapine is used in the treatment of ischemic cerebrovascular diseases, but it has a low bioavailability in the brain due to its poor physicochemical properties and the activity of P-glycoprotein efflux pumps located at the blood–brain barrier. In the present study, breviscapine-loaded solid lipid nanoparticles (SLN) coated with polyethylene glycol (PEG) derivatives were formulated and evaluated for their ability to enhance brain bioavailability. The SLNs were either coated with polyethylene glycol (40) (PEG-40) stearate alone (Bre-GBSLN-PS) or a mixture of PEG-40 stearate and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-PEG2000 (DSPE-PEG₂₀₀₀) (Bre-GBSLN-PS-DSPE) and were characterized both in vitro and in vivo. The mean particle size, polydispersity index, and entrapment efficiency for Bre-GBSLN-PS and Bre-GBSLN-PS-DSPE were 21.60 ± 0.10 and 22.60 ± 0.70 nm, 0.27 ± 0.01 and 0.26 ± 0.04, and 46.89 ± 0.73% and 47.62 ± 1.86%, respectively. The brain pharmacokinetic parameters revealed that the brain bioavailability of breviscapine from the Bre-GBSLN-PS and Bre-GBSLN-PS-DSPE was significantly enhanced (p < 0.01) with the area under concentration–time curve (AUC) of 1.59 ± 0.39 and 1.42 ± 0.58 μg h/mL of breviscapine, respectively, in comparison to 0.11 ± 0.02 μg h/mL from the commercial breviscapine injection. The ratios of the brain AUC for scutellarin in comparison with the plasma scutellarin AUC for commercial breviscapine injection, Bre-GBSLN-PS, and Bre-GBSLN-PS-DSPE were 0.66%, 2.82%, and 4.51%, respectively. These results showed that though both SLN formulations increased brain uptake of breviscapine, Bre-GBSLN-PS-DSPE which was coated with a binary combination of PEG-40 stearate and DSPE-PEG₂₀₀₀ had a better brain bioavailability than Bre-GBSLN-PS. Thus, the coating of SLNs with the appropriate PEG derivative combination could improve brain bioavailability of breviscapine and can be a promising tool for brain drug delivery.KEY WORDS: breviscapine, microdialysis, mixed PEGylation, P-glycoprotein (P-gp), solid lipid nanoparticles     

Development of Lipid-Based Nanoparticles for Enhancing the Oral Bioavailability of Paclitaxel

The current research work investigates the potential of solid lipid nanoparticles (SLNs) in improving the oral bioavailability of paclitaxel. Paclitaxel-loaded SLNs (PTX-SLNs) were prepared by modified solvent injection method using stearylamine as lipid, soya lecithin and poloxamer 188 as emulsifiers. SLNs were characterized in terms of surface morphology, size and size distribution, surface chemistry and encapsulation efficiency. Pharmacokinetics and bioavailability studies were conducted in male Swiss albino mice after oral administration of PTX-SLNs. SLNs exhibited spherical shape with smooth surface as analyzed by transmission electron microscopy (TEM). The mean particle size of SLNs was 96 ± 4.4 nm with a low polydispersity index of 0.162 ± 0.04 and zeta potential of 39.1 ± 0.8 mV. The drug entrapment efficiency was found to be 75.42 ± 1.5% with a loading capacity of 31.5 ± 2.1% (w/w). Paclitaxel showed a slow and sustained in vitro release profile and followed Higuchi kinetic equations. After oral administration of the PTX-SLNs, drug exposure in plasma and tissues was ten- and twofold higher, respectively, when compared with free paclitaxel solution. PTX-SLNs produced a high mean C _max (10,274 ng/ml) compared with that of free paclitaxel solution (3,087 ng/ml). The absorbed drug was found to be distributed in liver, lungs, kidneys, spleen, and brain. The results suggested that PTX-SLNs dispersed in an aqueous environment are promising novel formulations that enhanced the oral bioavailability of hydrophobic drugs, like paclitaxel and were quite safe for oral delivery of paclitaxel as observed by in vivo toxicity studies.     

多西他赛固体脂质纳米粒抗乳腺癌效果及机制研究

目的:探讨多西他赛固体脂质纳米粒抗乳腺癌效果及机制研究。方法:本实验采用MTT法考察了多西他赛固体脂质纳米粒对人乳腺癌MCF-7细胞增殖的抑制作用,采用流式细胞术检测多西他赛固体脂质纳米粒对MCF-7肿瘤细胞凋亡作用,并进一步应用Western-Blot印迹法观察多西他赛固体脂质纳米粒对MCF-7细胞中Src、E-cadherin、β-catenin蛋白表达的影响,探索了其抗乳腺肿瘤的作用机制。结果:多西他赛固体脂质纳米粒能够显著抑制人乳腺癌MCF-7肿瘤细胞的增殖,且浓度越高,抑制率越大(P0.05)。经25、50、100μg/m L多西他赛固体脂质纳米粒制剂作用24 h后,人乳腺癌细胞MCF-7的凋亡率分别为14.56%、21.21%、29.94%,细胞凋亡率随着药物浓度的增加而增加,且各实验组间比较有显著性差异(P0.05)。人乳腺癌MCF-7肿瘤细胞经不同浓度的多西他赛固体脂质纳米粒处理后,细胞中E-cadherin蛋白表达显著升高,Src、β-catenin蛋白表达显著降低,且呈现出明显的剂量依赖性。结论:多西他赛固体脂质纳米粒能够抑制人乳腺癌MCF-7细胞增殖,促进其凋亡,可能与下调β-catenin蛋白的表达,上调E-cadherin蛋白表达以及抑制Src激酶活性有关。     

Design and Characterization of Metformin-Loaded Solid Lipid Nanoparticles for Colon Cancer

Colorectal cancer is a global concern, and its treatment is fraught with non-selective effects including adverse side effects requiring hospital visits and palliative care. A relatively safe drug formulated in a bioavailability enhancing and targeting delivery platform will be of significance. Metformin-loaded solid lipid nanoparticles (SLN) were designed, optimized, and characterized for particle size, zeta potential, drug entrapment, structure, crystallinity, thermal behavior, morphology, and drug release. Optimized SLN were 195.01?±?6.03 nm in size, ?17.08?±?0.95 mV with regard to surface charge, fibrous in shape, largely amorphous, and release of metformin was controlled. The optimized size, charge, and shape suggest the solid lipid nanoparticles will migrate and accumulate in the colon tumor preventing its proliferation and subsequently leading to tumor shrinkage and cell death.     

Preparation and Evaluation of Diosgenin Nanocrystals to Improve Oral Bioavailability

Diosgenin (DSG), a well-known steroid sapogenin derived from Dioscorea nipponica Makino and Dioscorea zingiberensis Wright, has a variety of bioactivities. However, it shows low oral bioavailability due to poor aqueous solubility and strong hydrophobicity. The present study aimed to develop DSG nanocrystals to increase the dissolution and then improve the oral bioavailability and biopharmaceutical properties of DSG. DSG nanocrystals were prepared by the media milling method using a combination of pluronic F127 and sodium dodecyl sulfate as surface stabilizers. The physicochemical properties of the optimal DSG nanocrystals were characterized using their particle size distribution, morphology, differential scanning calorimetry, powder X-ray diffraction, Fourier transform infrared spectroscopy data, and solubility and dissolution test results. Pharmacokinetic studies of the DSG coarse suspension and its nanocrystals were performed in rats. The particle size and polydispersity index of DSG nanocrystals were 229.0?±?3.7 nm and 0.163?±?0.064, respectively. DSG retained its original crystalline state during the manufacturing process, and its chemical structure was not compromised by the nanonizing process. The dissolution rate of the freeze-dried DSG nanocrystals was significantly improved in comparison with the original DSG. The pharmacokinetic studies showed that the AUC_0–72h and C _max of DSG nanocrystals increased markedly (p?<?0.01) in comparison with the DSG coarse suspension by about 2.55- and 2.01-fold, respectively. The use of optimized nanocrystals is a good and efficient strategy for oral administration of DSG due to the increased dissolution rate and oral bioavailability of DSG nanocrystals.     

Development of Silymarin Self-Microemulsifying Drug Delivery System with Enhanced Oral Bioavailability

The objective of this work was to develop a self-microemulsifying drug delivery system (SMEDDS) for improving oral absorption of poorly water-soluble drug, silymarin. The pseudo-ternary phase diagrams were constructed using ethyl linoleate, Cremophor EL, ethyl alcohol, and normal saline to identify the efficient self-microemulsification region. The particle size and its distribution of the resultant microemulsions were determined using dynamic light scattering. The optimal formulation with the best self-microemulsifying and solubilization ability consisted of 10% (w/w) of ethyl linoleate, 30% of Cremophor EL, and 60% of ethyl alcohol. The release of silymarin from SMEDDS was significantly faster than that from the commercial silymarin preparation hard capsule (Legalon®). The bioavailability results indicated that the oral absorption of silymarin SMEDDS was enhanced about 2.2-fold compared with the hard capsule in fasted dogs. It could be concluded that SMEDDS would be a promising drug delivery system for poorly water-soluble drugs by the oral route.     

Solid Lipid Nanoparticles as Delivery Systems for Bioactive Food Components

The inclusion of bioactive compounds, such as carotenoids, omega-3 fatty acids, or phytosterols, is an essential requisite for the production of functional foods designed to improve the long-term health and well-being of consumers worldwide. To incorporate these functional components successfully in a food system, structurally sophisticated encapsulation matrices have to be engineered, which provide maximal physical stability, protect ingredients against chemical degradation, and allow for precise control over the release of encapsulated components during mastication and digestion to maximize adsorption. A novel encapsulation system initially developed in the pharmaceutical industries to deliver lipophilic bioactive compounds is solid lipid nanoparticles (SLN). SLN consist of crystallized nanoemulsions with the dispersed phase being composed of a solid carrier lipid–bioactive ingredient mixture. Contrary to larger colloidal solid lipid particles, specific crystal structures can be “dialed-in” in SLN by using specific surfactant mixtures and ensuring that mean particle sizes are below 100–200 nm. Moreover, in SLN, microphase separations of the bioactive compound from the solidifying lipid matrix can be prevented resulting in an even dispersion of the encapsulated compound in the solid matrix thereby improving chemical and physical stability of the bioactive. In this review article, we will briefly introduce the structure, properties, stability, and manufacturing of solid lipid particles and discuss their emerging use in food science.