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1.
Abstract

The intention of this study is to achieve higher entrapment efficiency (EE) of berberine chloride (selected hydrophilic drug) using nanoprecipitation technique. The solubility of drug was studied in various pH buffers (1.2–7.2) for selection of aqueous phase and stabilizer. Quality by design (QbD)-based 32 factorial design were employed for optimization of formulation variables; drug to polymer ratio (X1) and surfactant concentration (X2) on entrapment efficiency (EE), particle size (PS) and polydispersity index (PDI) of the nanoparticles. The nanoparticles were subjected to solid state analysis, in vitro drug release and stability study. The aqueous phase and stabilizer selected for the formulations were pH 4.5 phthalate buffer and surfactant F-68, respectively. The formulation (F-6) containing drug to polymer ratio (1:3) and stabilizer (F-68) concentration of 50?mM exhibited best EE (82.12%), PS (196.71?nm), PDI (0.153). The various solid state characterizations assured that entrapped drug is amorphous and nanoparticles are fairly spherical in shape. In vitro drug release of the F-6 exhibited sustained release with non-Fickian diffusion and stable at storage condition. This work illustrates that the proper selection of aqueous phase and optimization of formulation variables could be helpful in improving the EE of hydrophilic drugs by nanoprecipitation technique.  相似文献   

2.
Although the systemic administration of terbinafine is quite well tolerated, topical treatment of the local infections is often preferred. New formulation strategies in topical antifungal therapy represent the polymeric nanoparticles (NPs). We successfully employed the originally synthesized PLGA derivatives of branched architectures of various molar masses, branching ratio, and high number of terminal hydroxyl or carboxyl groups for compounding of terbinafine loaded nanoparticles by nanoprecipitation method. Employing the polymers with tailored properties allowed us to formulate the NPs with desired particle size, loading capacity for drug, mucoadhesive properties, and drug release profile. The hydrophobicity and the polyester concentration revealed the main impact on the NPs size ranging from 100 to 600?nm. The stability of the nanosuspension is demonstrated by zeta potential >25?mV, and polydispersity index values <0.2. We used terbinafine in its less dissolved form of the base to increase the drug loading and delay the release. Cationic surfactant as stabilizer give the NPs high positive surface charge enhancing the adhesion to the mucosal surfaces. All formulations provided prolonged sustained release of terbinafine for several days. Antimicrobial potential has been proven by agar-well diffusion method.  相似文献   

3.
The purpose of this study was to evaluate the effect of process (homogenization speed and evaporation time) and formulation (aqueous/organic phase ratio, surfactant concentration, polymer type and concentration, and drug amount) variables on the preparation of paclitaxel-loaded biodegradable polymeric nanoparticles using modified solvent evaporation technique. Thereafter, a formulation was selected and subjected to evaluation of inclusion of a co-surfactant for further reduction of particle size. Particle size, encapsulation efficiency and in-vitro drug release kinetics were evaluated. It was observed that the inclusion of vitamin E TPGS (0.01%), Poloxamer 188 (0.5%) or Tween 80 (0.25%) reduced the particle size of nanoparticles to 230, 244 or 301 nm from 438 nm, respectively. Encapsulation efficiency increased for both vitamin E TPGS and Poloxamer 188 up to concentration at 0.010% and 0.25%, respectively, while this was not the case for Tween 80. Comparison of drug release kinetics demonstrated that drug release accelerated from paclitaxel-loaded biodegradable nanoparticles prepared with the inclusion of Tween 80 but was delayed for Poloxamer 188 and vitamin E TPGS. Thus, it was concluded that the particle size of the nanoparticles could be reduced further and the paclitaxel release kinetics could easily be adjusted by taking advantage by the inclusion of a co-surfactant.  相似文献   

4.
Sodium ferulate (SF) loaded nanoparticles were prepared by desolvation procedure and subsequent cross-linking of the wall material of bovine serum albumin (BSA). Several factors in the nanoencapsulation process, such as the addition rate of the desolvation agent, composition of BSA and SF solution, amount of the cross-linker glutaraldehyde, were investigated to elucidate their influences on the particle size, zeta potential, drug loading and encapsulation efficiency of the resulted nanoparticles. The obtained spherical nanoparticles were negative charged with zeta potential from -20 to -40 mV, and characterized between 100 and 200 nm with a narrow size distribution. In the condition of introducing 1.0 mL 8% glutareldehyde per mg of BSA, the drug entrapment efficiency (EE) of 80% (w/w) and loading capacity of about 16% (w/w) could be achieved for the cross-linked BSA nanoparticles with SF encapsulated (SF-BSA-NP). And the drug EE was decreased along with the increasing amount of glutareldehyde used for cross-linking. The in vitro drug release properties of SF-BSA-NP behaved with an initial burst effect and then sustained-release stage. To some extent, the drug release rate could be adjusted by cross-linking with different amount of glutaraldehyde. Compared with SF solution, SF-BSA-NP showed a much higher drug distribution into liver and a lower drug concentration in other tissues, after intravenously injected to mice. So, BSA based nanoparticles might be a suitable controlled released carrier for the freely water-soluble drug SF and further hepatic targeted drug delivery.  相似文献   

5.
Poly(DL-lactic acid) (PLA), poly(-caprolactone) (PCL), and their copolymers (PLA-CL) with various monomer compositions were synthesized, and their properties as matrix for the sustained release of drugs were evaluated. The copolymerization technique produced very soft films which incorporated the drugs without deterioration of the elastic properties. Cisplatin and MD-805 were loaded in the films by casting the polymer solution containing the drugs. Fractions of the drugs released from the PLA-CL films were governed by the initial loading, the film thickness, and the polymer molecular weight. The drug release profiles obeyed the classical Fickian diffusion equation at least in the early stage, but significant hydrolytic degradation of the matrix polymers occurred in the later stage, influencing the kinetics of drug release. The monomer composition of copolymer affected the release profile more strongly than the initial molecular weight of the copolymer.  相似文献   

6.
目的 以壳聚糖(CS)为载体,研究其对重组人血管内皮抑制素(Endostar)的包封及控释能力.方法采用大分子复合法制备纳米粒,考察形成条件及冻干工艺,并对纳米粒的形态、包封率、体外释放及Endostar的完整性进行考察.结果CS与羧甲基纤维素钠( CMC - Na)的质量比介于6∶1~1∶2时可以形成纳米粒,粒径为1...  相似文献   

7.
目的:本研究以脂蟾毒配基(resibufogenin,RBG)为模型药物,以自制的乙交酯丙交酯共聚物-维生素E聚乙二醇1000琥珀酸酯(polylactide-co-glycolide-D-α-tocopheryl polyethylene glycol 1000 succinate,PLGA-TPGS)为载体材料,采用正交试验筛选制备脂蟾毒配基PLGA-TPGS纳米粒(RBG-loaded PLGA-TPGS nanoparticles,RPTN)的最佳处方和制备工艺,并对RPTN进行体外稳定性考察。方法:采用超声乳化-溶剂挥发法制备RPTN,用单一因素法分别考察主药与载体配比、TPGS水溶液浓度、超声功率、超声时间对RPTN的粒径、载药量和包封率的影响。根据单一因素考察的试验结果,设定因素水平表,通过正交试验筛选制备RPTN的最佳处方和制备工艺。采用影响因素、加速、长期试验考察RPTN的体外稳定性。结果:通过正交试验筛选出制备RPTN的最佳处方和制备工艺,即主药与载体比例为3∶10(W∶W),0.05%TPGS水溶液为乳化剂,超声功率250 W下超声10 min。6批RPTN的平均粒径、载药量和包封率分别为(152.3±2.5)nm、(18.4±0.3)%和(79.3±1.2)%(n=6)。在稳定性考察中,RPTN在影响因素、加速、长期试验中均表现出良好的稳定性。结论:筛选出制备RPTN的最佳处方和制备工艺,自制RPTN粒径较小、载药量和包封率较高,体外具有良好的稳定性。  相似文献   

8.
The nasal mucosa has many advantages as a potential site for drug and vaccine delivery. The present study has sought to exploit this route of delivery using microparticles composed of D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS) as a matrix material blended with poly(caprolactone) for nasal immunisation with diphtheria toxoid. Particles were prepared by a double emulsion method, followed by spray drying and the effect of TPGS on size, zeta potential, loading and release of antigen was assessed. Particles composed of TPGS-PCL blends were spherical, smooth and monodisperse, displaying increasing yields after spray drying with increasing concentrations of TPGS. The immune response to diphtheria toxoid loaded PCL-TPGS microspheres after nasal administration was shown to be higher than that achieved using PCL microspheres alone. We conclude that TPGS shows significant potential as a novel adjuvant either alone or in combination with an appropriate delivery system.  相似文献   

9.
This work evaluates the effects of paclitaxel loaded polymeric nanoparticles (NPs) composed of poly(D,L-lactic-co-glycolic acid) (PLGA) with vitamin E TPGS as emulsifier for oral chemotherapy. NPs prepared by a modified solvent extraction/evaporation technique were observed in spherical shape of 200-300 nm diameter with a high drug encapsulation efficiency (EE) of 80.9%. The TPGS-emulsified PLGA NPs formulation of paclitaxel was found of great advantages over that of Taxol®. The in vitro viability experiment showed that the NP formulation could be 1.28,1.38,1.12 times more effective than Taxol® after 24, 48, 72 h incubation with MCF-7 human breast cancer cell line at 2.5 μg/mL paclitaxel concentration. In vivo evaluation confirmed the advantages of the TPGS-emulsified PLGA NP formulation versus Taxol® in promoting oral bioavailability of paclitaxel. Such a NP formulation achieved more than 10 times higher oral bioavailability than Taxol®, which resulted 9.74-fold higher therapeutic effect and 12.56-fold longer sustainable therapeutic time than Taxol®. The present proof-of-concept experimental data proved that the formulation of vitamin E TPGS emulsified PLGA NPs is a promising approach for paclitaxel oral administration. Oral chemotherapy by NPs formulation is feasible. © 2010 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:3552-3560, 2010  相似文献   

10.
全反式维甲酸固体脂质纳米粒的制备及体内外评价   总被引:9,自引:2,他引:9  
目的以山嵛酸甘油酯(Compritol 888 ATO)为脂质材料,采用超声分散法制备维甲酸固体脂质纳米粒,并考察其体内外性质。方法选用脂溶性较高的维甲酸作为模型药物,采用超声分散法制备固体脂质纳米粒,并对其各种理化性质进行研究。考察了纳米粒的体外释放,以维甲酸溶液剂为对照,测定了两种纳米粒在大鼠体内的药代动力学参数。结果采用超声分散法可以简便、快速制备得到两种维甲酸固体脂质纳米粒,透射电镜测得纳米粒为圆球状,大小均匀。动态光散射法测得平均粒径分别为(158±9) nm和(89±11) nm。于4 ℃放置1年粒径无明显变化,载药量为3.3%,包封率大于95%。药物体外释放符合Weibull方程。与对照组相比,两种维甲酸固体脂质纳米粒静脉注射后药物在血液中的滞留时间显著延长。结论超声分散法适用于固体脂质纳米粒的制备。  相似文献   

11.
Acoustic monitoring of a fluidized bed coating process   总被引:1,自引:0,他引:1  
Bioeliminable co-polymers based on poly(methacryloylglycylglycine-OH(x)-co-hydroxypropylmethacrylamide(y)) were successfully converted into nanoparticles by using the co-precipitation technique. Human serum albumin (HSA) and a modified (beta-cyclodextrin were used, respectively, as model protein drug and stabilizer. Nanoparticles were characterized from a dimensional and morphological point of view by means of laser diffraction granulometry and scanning electron microscopy (SEM). The prepared nanoparticles displayed a monomodal diameter distribution in the range of 130 nm, confirmed by SEM micrographs. Protein loading efficiency and drug release kinetics investigations, carried out on bioeliminable nanoparticles loaded with fluoresceinated HSA (HSA-FITC), showed that protein loading is in the range of 60% with a typical time controlled release profile. In vitro cytotoxicity investigations of the polymer matrices and resulting nanoparticles were carried out by using different assays aimed at the evaluation of the interactions of the materials with cell metabolism and the cell membrane. On the whole, bioeliminable polymers and nanoparticles resulted in high cytocompatibility thus suggesting their suitability for biomedical applications.  相似文献   

12.
The encapsulation efficiency (EE) of hydrophobic drug into cubosomes was high by conventional methods, while poor for the hydrophilic drug. In this study, a remote loading method based on transmembrane pH-gradient was applied to prepare hydrophilic drug loaded cubosomes. Several hydrophilic drugs were selected and studied. Results showed just part of the investigated drugs were successfully loaded into cubosomes by the remote loading method, whereas all the drugs failed to be encapsulated by the high-pressure homogenization method. The EE based on remote loading method was affected by the solubility, LogP, number of rings, and polarizability of the drug independent of the number of hydrogen acceptor and hydrogen donor. And the drugs that had high EE by remote loading method were BCS class 1 or 2. In addition, the EE base on remote loading method was significantly affected by the external water pH of cubosomes and drug concentration. The size of drug-loaded cubosomes by remote loading method mainly depended on the pre-formed blank cubosomes, which was bigger than that by high-pressure homogenization method. The preparation method affected the liquid crystalline structure of acidic drug loaded cubosomes, while showed no obvious effect on that of basic drug loaded cubosomes. The release of drug was susceptible to the pH of release medium independent of the preparation method. The drug-loaded cubosomes prepared by different method all showed favorable stability during storage. The remote loading method was a promising approach for the efficient encapsulation of hydrophilic drug into cubosomes. This study laid a foundation for the application of remote loading method on the preparation of hydrophilic drug loaded cubosomes.  相似文献   

13.
The aim of this study was to formulate and evaluate microencapsulated controlled release preparations of zidovudine using ethyl cellulose as the retardant material with high entrapment efficiency and extended release. Microspheres were prepared by water-in-oil-in-oil (w/o/o) double emulsion solvent diffusion method. A mixed solvent system (MSS) consisting of acetonitrile and dichloromethane in a 1:1 ratio and light liquid paraffin were chosen as primary and secondary oil phases, respectively. Span 80 was used as the surfactant for stabilizing the secondary oil phase. The prepared microspheres were white, free flowing and spherical in shape and characterized by drug loading, infrared spectroscopy (IR), differential scanning colorimetry (DSC) and scanning electron microscopy (SEM). The in vitro release studies were performed using PH 7.4 phosphate buffer. The drug loaded microspheres showed 41–55% of entrapment and release was extended up to 18–20?h. The infrared spectra and DSC and DTA thermograms showed stable character of zidovudine in the drug loaded microspheres and revealed the absence of drug-polymer interactions. SEM studies showed that the microspheres are spherical and porous in nature. Data obtained from in vitro release were fitted to various kinetic models and high correlation was obtained in the Higuchi model. The drug release was found to be diffusion controlled.  相似文献   

14.
目的制备一种生物可降解、生物相容性良好的姜黄素纳米粒子,并对其体外药物释放行为进行考察。方法采用开环聚合法制备生物可降解的PCL-PEG-PCL三嵌段聚合物,然后采用乳液挥发法制备负载姜黄素的PCL-PEG-PCL纳米粒子,通过透射电镜观察所制备纳米粒子的形貌特征,动态光散射(DLS)测定粒径,采用HPLC测定纳米粒子的包封率和载药量,同时考察其体外药物释放行为。结果姜黄素纳米粒子具有球形结构,粒径在200 nm左右,载药量为(14.23±0.35)%,3 d体外累积释药量65%。结论所制备的姜黄素纳米粒子具有较高的载药量和包封率,同时体外药物释放实验证实姜黄素纳米粒子具有良好的缓释功能。  相似文献   

15.
A hydrophilic and temperature-induced degradation drug, vinorelbine bitartrate (VB)-loaded solid lipid nanoparticles (SLNs) were prepared by a cold homogenization technique. The physicochemical properties of the SLNs, with various lipid composition, drug content and altered homogenizing times, were investigated. The mean particle size of the SLNs ranged from 150 to 350 nm. The enhancement of lecithin content in lipid matrix resulted in smaller particle of SLNs. The atomic force microscopy (AFM) images displayed that the shape of the SLNs was irregular sphere with smooth surface. The drug entrapment efficiency (EE) could be improved with the increasing of lecithin or oleic acid content in lipid matrix, and reduced with the added amount of drug. The highest EE and drug loading capacity (DL) could reach up to 80 and 6.6%, respectively. The studies of drug release showed that the drug release could last for 48 h, and the rate was delayed by the addition of lecithin or oleic acid in the formulations. The physical stability experiment indicated that the SLNs were stable for 2 months under room temperature. Moreover, the cellular cytotoxicity of VB against MCF-7 cells could be improved by the entrapment of SLNs.  相似文献   

16.
Poly(lactide-co-glycolide) nanoparticles loaded with pilocarpine hydrochloride were prepared by the high-pressure emulsification-solvent evaporation method. The nanoparticles were produced using polyvinylalcohol (PVA), carbomer (Carbopol 980) or poloxamer (Lutrol F-68) as stabilizers during emulsification. The influence of pressure and number of cycles on the nanoparticle properties was investigated. For comparison, nanoparicles without high-pressure treatment of the emulsion were made. The nanoparticle size, drug loading and release properties depended strongly on the homogenization pressure and number of cycles applied. Nanoparticles obtained without high pressure homogenization showed larger size and high values of polydispersity index, especially when carbopol and poloxamer were used as emulsifiers. Drug loading and encapsulation efficiency of all samples also decreased with pressure. The low drug loading could be due to two reasons. First, the high pressure promoted drug diffusion out of protoparticles during emulsification either by size reduction or shear forces. Secondly, the characteristics of the outer water phase of the emulsion also influenced the nanoparticle drug loading. This was proven by the different drug loadings measured when nanoparticles were made with PVA, carbopol or poloxamer at equal pressures applied. The main factor influencing the release properties of nanoparticles was the pressure used during emulsification. Faster drug release was observed from nanoparticles obtained after high-pressure emulsification compared to those prepared without homogenization of the emulsion.  相似文献   

17.

Background

Repaglinide is an efficient anti-diabetic drug which is prescribed widely as multi-dosage oral daily regimens. Due to the low compliance inherent to each multi-dosage regimen, development of prolonged-release formulations could enhance the overall drug efficacy in patient populations.

Methods

Repaglinide-loaded solid lipid nanoparticles (SLNs) were developed and characterized in vitro. Various surfactants were used in this study during the nanocarrier preparation procedure and their corresponding effects on some physicochemical properties of SLNs such as size, zeta potential; drug loading parameters and drug release profiles was investigated. Stearic acid and glyceryl mono stearate (GMS) were used as lipid phase and phosphatidylcholin, Tween80, Pluronic F127, poly vinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) were used as surfactant/stabilizer.

Results

The results showed some variations between formulations; where the Tween80-based SLNs showed smallest size, the phosphatidylcholin-based SLNs indicated most prolonged drug release time and the highest loading capacity. SEM images of these formulations showed morphological variations and also confirmed the nanoscale size of these particles. The FTIR and DSC results demonstrated no interaction between drug and excipients. The invitro release profiles of different formulations were studied and observed slow release of drug from all formulations. However significant differences were found among them in terms of their initial burst release as well as the whole drug release profile. From fitting these data to various statistical models, the Peppas model was proposed as the best model to describe the statistical indices and, therefore, mechanism of drug release.

Conclusion

The results of this study confirmed the effect of surfactant type on SLNs physicochemical properties such as morphological features, loading parameters, particle sizes and drug release kinetic. With respect to the outcome data, the mixture of phosphatidylcholin/Pluronic F127 was selected as the best surfactant/stabilizer to coat the lipid core comprising stearic acid and GMS.  相似文献   

18.
This work focused on a new technique for the preparation of doxorubicin (DOX) loaded chitosan (CS) nanoparticles (DOX-CS) — formation by electrospray ionization in the presence of tripolyphosphate (TPP) as the stabilizer. The working distance, needle gauge, flow rate, stirring rate, electrospraying voltage and DOX to CS molar ratio were sequentially and individually optimized and found to be a 26 gauge needle, an applied voltage of 13 kV, a flow rate of 0.5 mL/h, a working distance of 8 cm and a stirring rate of 400 rpm. The incorporation of chemically unchanged DOX with the CS into the particles was ascertained by Fourier transformed infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Under these optimized conditions, the DOX-CS particles were found to be nanoparticles of approximately 300–570 (dry particles) or 530–870 nm diameter (hydrated particles), with a PDI and SPAN polydispersity indices of 0.97–0.82 and 0.62–0.64, respectively, for initial DOX loading levels of 0.25–1%, as determined by SEM and particle size analyzer, respectively. Moreover, a high encapsulation efficiency (EE) of DOX into the nanoparticles was attained, ranging from 63.4 to 67.9% EE at 1 to 0.25% DOX loading. Finally, the in vitro DOX release behaviors of the DOX-CS particles revealed a prolonged release of DOX over at least seven hours.  相似文献   

19.
We disclose a self nanoprecipitating preconcentrate (SNP) of tamoxifen citrate (TMX), which forms TMX loaded polymeric nanoparticles, on dilution with aqueous media. SNP comprised TMX, polymer (Kollidon SR) and surfactant/s dissolved in a pharmaceutically acceptable vehicle. Binary surfactant mixtures of Aerosol OT (AOT) with Tween 80 revealed synergistic reduction in surface tension to enable both high entrapment efficiency (EE) and low particle size (PS). Synergism of the surfactants was confirmed by molecular interaction parameter(β(σ)). Combination of AOT and Tween 80 resulted in EE (~85%) and PS (<250nm). Formation of TMX-KSR nanoparticles in situ was reproducible under most experimental conditions and exhibited pH independent behavior. Dilution volume (>80mL) influenced both PS and EE while dilution temperature influenced only PS. Marginal increase in size was evident at the end of 1h nevertheless was not of concern as TMX SNP exhibited near complete release in 1h. DSC and XRD studies revealed amorphous nature of TMX in nanoparticles. FTIR imaging confirmed uniform distribution of TMX in nanoparticles. ESEM and TEM revealed spherical nanoparticles. Biodistribution studies of (99m)Tc labeled TMX SNP in rats revealed no significant absorption however oral pharmacokinetics revealed enhanced oral bioavailability of TMX (165%) compared to TMX suspension. SNP presents a new in situ approach, for design of drug loaded polymeric nanoparticles.  相似文献   

20.
目的制备载有姜黄素的单油酸甘油酯(GMO)/聚乙二醇1000维生素E琥珀酸酯(TPGS)/壳聚糖(CS)脂质纳米粒,考察该脂质纳米粒在提高药物稳定性方面的潜能。方法采用乳化-高压均质法制备载有姜黄素的GMO/TPGS/CS脂质纳米粒,对该纳米粒进行粒径及分布、zeta电位、微观形态、物理稳定性、UV-Vis光谱学及体外释放动力学等表征。并以姜黄素水溶液为对照,测定该脂质纳米粒在高温、光照、强碱等条件下的稳定性。结果该纳米粒为球形或类球形,平均粒径为(93.8±2.80)nm,多分散系数为(0.156±0.063),zeta电位为+(16.76±1.52)mV;有良好的物理稳定性;UV-Vis光谱显示,姜黄素可能通过疏水作用结合在纳米粒上,这使得药物产生缓释效果,符合Weibull方程。相比姜黄素水溶液,在高温、光照及强碱等强条件下,包封在纳米粒中的姜黄素降解程度显著减小。结论本试验证明了结合使用GMO/TPGS/CS制备姜黄素脂质纳米粒,可显著提高姜黄素的稳定性。  相似文献   

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