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1.
In this study, water-in-oil (W/O) miniemulsion was used as nanoreactor to prepare solid lipid nanoparticles (SLN) by solvent diffusion method. n-Hexane, Tween 80 and Span 80 were used as the oil phase and surfactant combination for preparation of W/O miniemulsion, respectively. The stable miniemulsion with the particle size of 27.1 ± 7.6 nm was obtained when the composition of water/Tween 80/Span 80/n-hexane was 1 ml/18 mg/200 mg/10 ml. Clobetasol propionate (CP) was used as a model drug. The physicochemical properties of the SLN, such as particle size, zeta potential, surface morphology, drug entrapment efficiency, drug loading capacity and in vitro drug release behaviors were investigated, comparing with those of SLN prepared by conventional aqueoethod. The SLN prepared by the novel method displayed smaller particles size and higher dus solvent diffusion mrug entrapment efficiency than those of SLN prepared by the conventional method. The drug entrapment efficiency decreased with increasing of charged amount of drug, and 15.9% of drug loading was achieved as the charged amount of drug was 20%. The in vitro drug release tests indicated that the drug release rate was faster than that of SLN prepared by the conventional method, and the drug content in SLN did not affect the in vitro drug release profile.  相似文献   

2.
Polymeric nanoparticles constitute an important drug delivery system with controlled release profile. This article describes a new way to produce polymeric nanocapsules using a vegetable oil nanoemulsion as template. The process occurs in two steps: First, a nanoemulsion was obtained with a low-energy method based on phase inversion emulsification, using 2-ethylhexyl acrylate as lipophilic monomer. The in situ polymerization of the nanoemulsion droplets is induced by the addition of polymerization catalyzers. The mean size of the polymeric nanoparticles was evaluated by photon correlation spectroscopy and atomic force microscopy. Both techniques showed the formation of polymeric nanocapsules with a mean particle size less than 300 nm.  相似文献   

3.
The current research aimed to fabricate ondansetron nanostructured lipid carriers (OND-NLCs) and incorporate them into a suppository base to manage chemotherapy-induced vomiting and nausea, which offer the advantage of both rapid onset and prolonged release. NLCs were fabricated by adopting the solvent diffusion method. The binary lipid mixture of oleic acid (liquid lipid) and lauric acid (solid lipid) were prepared in distinct ratios. The NLCs were characterized concerning the surface charge, size, drug encapsulation efficiency, and surface morphology. In addition, the influence of surfactant, co-surfactant, and lipid on entrapment efficiency and particle size was investigated. Phosphate buffer having pH 7.4 is used for evaluating in vitro drug release by utilizing a dialysis membrane. Various kinetics models were used to estimate the drug release kinetics of fabricated nanostructured lipid carriers. The particle size of the NLCs was calculated between 101 and 378 nm with negative zeta potential on the NLC’s surface. The entrapment efficiency was found between 68 and 87%. Scanning Electron Microscopic analysis showed the spherical shape of nanostructured lipid carriers. The dissolution profile of the ondansetron-loaded NLC suppository depicts biphasic behavior of firstly burst release then slow release was observed. The diffusion controlled release was evident from kinetic modeling. The succeeding step comprehended the fabrication and characterization of NLC-based suppositories utilizing NLC formulations that demonstrated the combined advantage of rapid onset, prolonged release, and better in vivo bioavailability as compared to control suppository.  相似文献   

4.
8-Methoxsalen was vehicled in nanoemulsion and in solid lipid nanoparticles (SLN) prepared by the hot homogenization technique in order to be used in topical psoralen UVA (PUVA) therapy. Drug entrapment efficiency in nanoparticles was improved by choosing the appropriate lipid matrix. The use of α-tocopherol in the lipid phase reduces 8-methoxsalen induced photooxidation of porcine skin, which was evaluated in vitro by a malondialdehyde (MDA) test: This result is promising to reduce in vivo human skin irritation after PUVA therapy, which can be attributed to skin photooxidation.  相似文献   

5.
The aim of the present study was to develop controlled drug delivery systems based on nanotechnology. Two different nanocarriers were selected, chitosan-alginate nanoparticles as hydrophilic and solid lipid nanoparticles as lipophilic carriers. Nanoparticles were prepared and characterized by evaluating particle size, zeta potential, SEM pictures, DSC thermograms, percentage of drug loading efficiency, and drug release profile. The particle size of SLNs and Chi/Alg nanoparticles was 291 ± 5 and 520 ± 16. Drug loading efficiency of Chi/Alg and SLN particles were 68.98 ± 5.5% and 88 ± 4.5%. The drug release was sustained with chitosan-alginate system for about 45 hours whereas for SLNs >98% of the drug was released in 2 hours. Release profile did not change significantly after freeze drying of particles using cryoprotector. Results suggest that under in vitro condition chitosan/alginate systems can act as promising carriers for ciprofloxacin and may be used as an alternative system in sustained delivery of ciprofloxacin.  相似文献   

6.
Nanostuctured lipid carriers (NLC) based on mixture of solid lipids with spatially incompatible liquid lipids are a new type of lipid nanoparticles, which offer the advantage of improved drug loading capacity and release properties. In present study, stearic acid (SA) nanostuctured lipid carriers with various oleic acid (OA) content were successfully prepared by solvent diffusion method in an aqueous system. The size and surface morphology of nanoparticles were significantly influenced by OA content. As OA content increased up to 30 wt%, the obtained particles showed pronounced smaller size and more regular morphology in spherical shape with smooth surface. Compared with solid lipid nanoparticles (SLN), NLC exhibited improved drug loading capacity, and the drug loading capacity increased with increasing OA content. These results were explained by differential scanning calorimetry (DSC) investigations. The addition of OA to nanoparticles formulation resulted in massive crystal order disturbance and less ordered matrix of NLC, and hence, increased the drug loading capacity. The drug in vitro release behavior from NLC displayed biphasic drug release pattern with burst release at the initial stage and prolonged release afterwards, and the successful control of release rate at the initial stage can be achieved by controlling OA content.  相似文献   

7.
The aim of this study is the solid-state characterization of solid lipid nanoparticles (SLN) based on Compritol® 888 (C888) and Lutrol® F68 (F68), loaded with silver sulfadiazine (AgSD), used to develop sponge-like dressings to treat chronic skin ulcers such as decubitis and leg ulcers. Silver compounds like AgSD, in fact, are used to prevent and/or to treat wound colonization that could impair healing, also in the case of antibiotic-resistant bacteria. Thermal analysis, with support from powder X-ray diffractometry and Fourier transform infrared spectroscopy, is used to characterize lipid and drug bulk, unloaded and drug-loaded SLN. In particular, differential scanning calorimetry is used to investigate the degree of crystallinity and the solid-state modification of lipid, two parameters correlated to drug incorporation and drug release rates. The solid-state characterization demonstrates AgSD entrapment in C888 as a core enclosed into F68 shell. AgSD SLN are also stored at different temperatures 25 and 37 °C, respectively, to study the effect of storage conditions, that induce an increase of the lipid crystallinity index correlated to drug release from the lipid matrix.  相似文献   

8.
The objective of present research work was to formulate and evaluate topical gel containing tretinoin–cyclodextrin (CD) binary complex loaded into nanostructured lipid carriers (NLCs). Use of cyclodextrin and nanolipid carrier together in a system produced a synergistic effect by increasing the drug release and skin permeation, thus improving the overall therapeutic effect. Two different cyclodextrins i.e. β-CD and its water soluble polymeric derivative epichlorohydrin-β-cyclodextrin (EPI-β-CD) were used to obtain binary inclusion complex of drug-cyclodextrin (D-CD) systems by two different techniques (kneading and co-evaporation). The prepared solid complexes were characterized by FTIR, DSC, XRD etc. and the best system was selected for loading into nanolipid carriers. NLC comprising glyceryl mono stearate (GMS) and oleic acid were obtained by slightly modified emulsification evaporation method. Four different formulations of NLCs were suitability characterized for particle size, zeta potential, entrapment efficiency, drug loading and drug release. EPI-β-CD was found to be more effective than β-CD in enhancing solubility and dissolution properties of tretinoin. The most effective NLC formulation was incorporated into carbopol hydrogel which showed better permeation properties than that of the reference gel (0.1%).  相似文献   

9.
以可生物降解材料硬脂酸为载体, 以葛根总黄酮为模型药物, 采用乳化蒸发-低温固化法制备固体脂质纳米粒. 采用透射电镜研究载药纳米粒形态, 激光粒度分析仪测定其粒径, X射线衍射仪进行物相鉴别, 并对纳米粒的包封率及体外释药特性等进行了研究. 分析结果表明, 所制备硬脂酸固态脂质纳米粒为类球实体, 粒径分布比较均匀, 平均粒径为(263.82±3.6) nm, 包封率为(67.53±0.12)%. X射线衍射分析证明药物以分子或细小粒子分散于脂质骨架中. 体外释药研究结果表明, 纳米粒体外释药先快后慢, 12 h累积释药50%, 包封于降解材料骨架内的药物通过骨架溶蚀缓慢释放. 药物的体外释放符合Higuchi方程.  相似文献   

10.
In order to introduce hydrophilic peptide drugs into solid lipid nanoparticles (SLN), a technique of combining hydrophobic ion pairing (HIP) and non-aqueous oil-in-oil (O/O) emulsion-evaporation was developed. Leuprolide (LR) was selected as the model drug, while sodium stearate (SA-Na) was used as the negative charged ion pairing material. The formation of leuprolide-sodium stearate (LR-SA-Na) complex was confirmed by differential scanning calorimetry (DSC). It was observed that when the molar ratio of SA-Na/LR reached 2/1, ca 88.5% LR was incorporated into the hydrophobic ion complexes with SA-Na. Compared with the conventional method of solvent diffusion in an aqueous system, the efficiency of LR drug entrapment with SLN increased from 28.0% to 74.6% by the combined technique of HIP and O/O emulsion-evaporation. In vitro drug release tests revealed that employing technique of HIP obviously reduced the burst release and slowed down the rate of drug release. At meanwhile, applying the method of non-aqueous O/O emulsion-evaporation, the longer time of drug release but relatively higher drug burst release ratio was observed in comparison with those by the solvent diffusion method in an aqueous system. The drug entrapment and release behaviors of LR-SA-Na SLN prepared by the O/O emulsion-evaporation method suggested that it could potentially be exploited as an oral delivery system for leuprolide.  相似文献   

11.
Treatment of herpes simplex infection requires high and frequent doses of oral acyclovir to attain its maximum therapeutic effect. The current therapeutic regimen of acyclovir is known to cause unwarranted dose-related adverse effects, including acute kidney injury. For this reason, a suitable delivery system for acyclovir was developed to improve the pharmacokinetic limitations and ultimately administer the drug at a lower dose and/or less frequently. In this study, solid lipid nanoparticles were designed to improve the oral bioavailability of acyclovir. The central composite design was applied to investigate the influence of the materials on the physicochemical properties of the solid lipid nanoparticles, and the optimized formulation was further characterized. Solid lipid nanoparticles formulated from Compritol 888 ATO resulted in a particle size of 108.67 ± 1.03 nm with an entrapment efficiency of 91.05 ± 0.75%. The analyses showed that the optimum combination of surfactant and solid lipid produced solid lipid nanoparticles of good quality with controlled release property and was stable at refrigerated and room temperature for at least 3 months. A five-fold increase in oral bioavailability of acyclovir-loaded solid lipid nanoparticles was observed in rats compared to commercial acyclovir suspension. This study has presented promising results that solid lipid nanoparticles could potentially be used as an oral drug delivery vehicle for acyclovir due to their excellent properties.  相似文献   

12.
Nanostructured lipid carriers (NLC) made from mixtures of solid and spatially incompatible liquid lipids were prepared by melt-emulsification. Their drug loading capacity and releasing properties of progesterone were compared with those of solid lipid nanoparticles (SLN), and the NLC prepared by solvent diffusion method. Monostearin (MS) and stearic acid (SA) were used as solid lipid, whilst the oleic acid (OA) was used as liquid lipid. Properties of carriers such as the particle size and its distribution, drug loading, drug encapsulation efficiency and drug release behavior were investigated. As a result, the drug encapsulation efficiencies were improved by adding the liquid lipid into the solid lipid of nanoparticles. The drug release behavior could be adjusted by the addition of liquid lipid, and the NLC with higher OA content showed the faster rate of drug releasing. NLC had higher efficiency of encapsulation and slower rate of drug release than those of NLC prepared by solvent diffusion method. On the other hand, the NLC with higher drug loading was obtained, though the drug encapsulation efficiency was decreased slightly due to the increase of the amount of drug. The NLC modified with polyethylene glycol (PEG) was also prepared by using polyethylene glycol monostearate (PEG-SA). It was observed that the incorporation of PEG-SA reduced the drug encapsulation efficiency, but increased the rate of drug release. A sample with almost complete drug release in 24 h was obtained by modifying with 1.30 mol% PEG-SA. It indicated that the modified NLC was a potential drug delivery system for oral administration.  相似文献   

13.
Nanostructured lipid carriers (NLC) made from mixtures of solid and spatially incompatible liquid lipids were prepared by melt-emulsification. Their drug loading capacity and releasing properties of progesterone were compared with those of solid lipid nanoparticles (SLN), and the NLC prepared by solvent diffusion method. Monostearin (MS) and stearic acid (SA) were used as solid lipid, whilst the oleic acid (OA) was used as liquid lipid. Properties of carriers such as the particle size and its distribution, drug loading, drug encapsulation efficiency and drug release behavior were investigated. As a result, the drug encapsulation efficiencies were improved by adding the liquid lipid into the solid lipid of nanoparticles. The drug release behavior could be adjusted by the addition of liquid lipid, and the NLC with higher OA content showed the faster rate of drug releasing. NLC had higher efficiency of encapsulation and slower rate of drug release than those of NLC prepared by solvent diffusion method. On the other hand, the NLC with higher drug loading was obtained, though the drug encapsulation efficiency was decreased slightly due to the increase of the amount of drug. The NLC modified with polyethylene glycol (PEG) was also prepared by using polyethylene glycol monostearate (PEG-SA). It was observed that the incorporation of PEG-SA reduced the drug encapsulation efficiency, but increased the rate of drug release. A sample with almost complete drug release in 24 h was obtained by modifying with 1.30 mol% PEG-SA. It indicated that the modified NLC was a potential drug delivery system for oral administration.  相似文献   

14.
Tryptanthrin is an ancient medicine which recently was also found to have a function of downregulating multidrug resistance (MDR). However, tryptanthrin is insoluble in water, which limits its availability for delivery into cancer cells. There is a need to improve delivery systems to increase the inhibition of MDR. The aim of this study was to employ nanoparticles encapsulating tryptanthrin to improve the delivery and promote the sustained release of this drug. The approach was to encapsulate tryptanthrin in various nanoparticles, including solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), and lipid emulsions (LEs). We compared the particle size and zeta potential of these nanoparticles, and evaluated the partitioning behavior of tryptanthrin in them. We also determined the release kinetics of tryptanthrin from these nanoparticles. Moreover, cellular cytotoxicity toward and uptake of tryptanthrin-loaded nanoparticles by human breast cancer cells were determined. We found that the mean particle size of NLCs was lower, and the partition coefficient was higher than those of SLNs, and an increased tryptanthrin release rate was found with the NLC delivery system. NLCs achieved the sustained release of tryptanthrin without an initial burst. In particular, the NLC-C formulation, composed of a mixture of Compritol and squalene as the core materials, showed the highest release rate and cytotoxic effect. Confocal laser scanning microscopic images confirmed drug internalization into cells which enhanced the endocytosis of the particles. These results suggested that NLCs can potentially be exploited as a drug carrier for topical or intravenous use in the future.  相似文献   

15.
Treatment of cancer is one of the most challenging problems and conventional therapies are inadequate for targeted, effective and safe therapy. Development of nanoparticle-based drug delivery systems emerge as promising carriers in this field to ensure delivery of anticancer drug to tumor site. The aim of this study was to design hydroxypropyl-β-cyclodextrin (CD) coated nanoparticles using poly(ε-caprolactone) (PCL) and its derivative poly(ethylene glycol)-block-poly(ε-caprolactone) (mePEG-PCL) to be applied as implants to tumor site following surgical operation in cancer patients. CD coated PCL and mePEG-PCL nanospheres were developed to encapsulate poorly soluble chemotherapeutic agent docetaxel (DOC) to improve solubility of drug and to enhance cellular penetration with longer residence time and higher local drug concentration. Nanospheres were prepared according to the nanoprecipitation method and coated with hydroxypropyl-β-cyclodextrin (Cavasol® W7HP). Cyclodextrin coating was performed for higher drug encapsulation and controlled but complete drug release from nanoparticles. Nanoparticle diameters varied between 60 and 136 nm depending on polymer used for preparation and coating. All nanoparticles have negative surface charge and zeta potential values varied between ?22 and ?37 mV. Encapsulation efficiency of formulations were found to be between 46 and 73 % and CD coated nanoparticles have significantly higher entrapment efficiency. Drug release profiles of nanoparticles were similar to each other and all formulations released encapsulated drug in approximately 12 h. Especially, CD-PCL nanoparticles were found to have highest entrapment efficiency and anticancer efficacy against MCF-7 human breast adenocarcinoma cell lines. Our study proved that polycaprolactone and its PEGylated derivatives can be suitable for development of implantable nanoparticles as a potential drug delivery system of DOC for cancer treatment and a good candidate for further in vivo studies.  相似文献   

16.
The objective of the present study was to employ suitable adsorbent with free flowing characteristics for improving the stability and physical properties of solid lipid nanoparticles (SLN) for oral administration. Stearic acid based nanoparticles of carvedilol phosphate were fabricated by solvent emulsification evaporation technique in sodium taurocholate solution prepared in pH 7.2 buffers (I—KH2PO4/NaOH or II—NaH2PO4/Na2HPO4) with 1% polyvinyl alcohol. Nanoparticles were then adsorbed by passing the nanodispersion through a Neusilin US2 (adsorbent) column. Interestingly, scanning electron microscopy revealed round deformed and even collapsed nanoparticles in Buffer-I and discrete spherical to ellipsoidal nanoparticles in Buffer-II which indicates the inability of nanoemulsion to crystallize and form SLN in Buffer-I. The successful formation of SLN in Buffer-II was confirmed by differential scanning calorimetry and X-ray diffraction. The retention of SLN from the nanodispersion by adsorption on the adsorbent imparted good flow property and resulted in a marked stability improvement of the formulation in terms of drug retention efficiency and release profile as compared to the simple nanosuspension. In conclusion, the adsorbent technology would be instrumental in imparting additional features to the existing conventional colloidal system for pharmaceutical application which would ease the process of capsule filling at industrial scale, simplify the handling of formulations by patients and can significantly improve the shelf life of the product for a longer period of time as compared to liquid formulations.  相似文献   

17.
This study aimed to investigate the role of different factors affecting the size of solid lipid nanoparticles (SLN), prepared by the emulsification-solvent evaporation method. A double factorial design was conducted so as to cover a wide range of sizes, highlighting zones with different behaviour with respect to changes in the controlled variables: lipid concentration, solvent:lipid ratio and emulsifier concentration. The solvent:lipid ratio constituted the main factor influencing particle size. Increasing the amount of solvent induced a decrease in the size. This was a general trend, essentially independent from solvent and lipid type. The amount of emulsifier had a non-trivial impact on size, depending on whether systems were located below, above or close to the optimal surface coverage. The amount of lipid had a limited influence upon particle size, being more relevant for lower lipid concentrations. An optimal formulation was selected for intermediate levels of the three variables. Sonication reduced both particle size and polydispersity. These particles were also tested as drug carriers using simvastatin as a model of lipophilic drug. SLN were able to entrap a high amount of simvastatin, with little effect upon size and zeta potential, constituting a promising carrier for lipophilic drugs.  相似文献   

18.
The objective of the present investigation was to develop microemulsion-based transdermal systems of highly water soluble drug, Atenolol, by quality by design technique. Atenolol-loaded W/O microemulsions were optimized using D-optimal design with concentrations of oil, surfactants mixture, and water as independent variables, which was converted into microemulsion-based gel (MBG). The results of in vitro permeation of the optimized batch of Atenolol-loaded MBG revealed significant increase in permeability parameters as compared to its convention gel. All results suggested suitability of W/O type MEs as carriers for transdermal delivery of highly water soluble drug, Atenolol.  相似文献   

19.
In the present study eugenol loaded solid lipid nanoparticles (SLN) was prepared and characterized for particle size, polydispersity index, zeta potential, encapsulation efficiency, in vitro release and in vivo antifungal activity. Effect of addition of liquid lipid (caprylic triglyceride) to solid lipid (stearic acid) on crystallinity of lipid matrix of SLN was determined by using Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD) techniques. Transmission electron microscopy (TEM) was carried out to determine the morphology of SLN. In vivo antifungal activity of eugenol loaded lipid nanoparticles was evaluated by using a model of oral candidiasis in immunosuppressed rats. Particle size results showed that d(90) of SLN(1) (single lipid matrix) and SLN(2) (binary lipid matrix) was 332±14.2 nm and 87.8±3.8 nm, respectively. Polydispersity index was found to be in the range of 0.27-0.4 which indicate moderate size distribution. Encapsulation efficiency of SLN(2) (98.52%) was found to be more than that of SLN(1) (91.80%) at same lipid concentration (2%, w/v). Increasing of the solid lipid concentration from 2% (w/v) to 4% (w/v) resulted in increase in encapsulation efficiency and the particle size. SLN(2) shows faster release of eugenol than that of SLN(1) due to smaller size and presence of liquid lipid which provide less barriers to the diffusion of drug from matrix. TEM study reveals the spherical shape of SLN. FT-IR, DSC and XRD results indicate less crystallinity of SLN(2) than that of SLN(1). In vivo studies show no significant difference in log cfu value of all the groups at 0 day. At 8th day, log cfu value of group treated with saline (control), standard antifungal agent, eugenol solution, SLN(1) and SLN(2) was found to be 3.89±.032, 2.69, 3.39±.088, 3.19±.028 and 3.08±0.124, respectively. The in vivo study results indicate improvement in the antifungal activity of eugenol when administrated in the form of SLN.  相似文献   

20.
This study focuses on the physicochemical characterization of lipid materials useful for the production of the so-called solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC). The chosen lipids were Dynasan®114 (glyceril trimyristate) and Dynasan®118 (glyceril tristearate) as solid lipids (SL), melting temperature above 80 °C, and Miglyol®812 (caprylic/capric triglyceride) and Miglyol®840 (propylene glycol dicaprylate/dicaprate) as liquid lipids (LL), crystallizing below ?15 °C. Raw lipids (pure or SL:LL mixtures) were analyzed by differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD), and Polarized Light Microscopy (PLM), before and after tempering at 80 °C for 1 h. The selected SL:LL combination was 70% (Dynasan®114 and 118) and 30% (Miglyol®812 and 840) for the production of SLN and NLC by high-pressure homogenization (HPH), respectively. Particles with a mean size of 200 nm (polydispersity index <0.329) and zeta potential of ?15 mV were obtained, and their long-term stability was confirmed for 3 months of storage at 7 °C.  相似文献   

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