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1.
Limited aqueous solubility of exemestane leads to high variability in absorption after oral administration. To improve the solubility and bioavailability of exemestane, the self-microemulsifying drug delivery system (SMEDDS) was developed. SMEDDS comprises of isotropic mixture of natural or synthetic oil, surfactant, and cosurfactant, which, upon dilution with aqueous media, spontaneously form fine o/w microemulsion with less than 100 nm in droplet size. Solubility of exemestane were determined in various vehicles. Ternary phase diagrams were plotted to identify the efficient self-emulsification region. Dilution studies, droplet size, and zeta potential of the formulations were investigated. The release of exemestane from SMEDDS capsules was studied using USP dissolution apparatus in different dissolution media and compared the release of exemestane from a conventional tablet. Oral pharmacokinetic study was performed in female Wistar rats (n = 8) at the dose of 30 mg kg−1. The absorption of exemestane from SMEDDS form resulted in about 2.9-fold increase in bioavailability compared with the suspension. Our studies illustrated the potential use of SMEDDS for the delivery of hydrophobic compounds, such as exemestane by the oral route.Key words: bioavailability enhancement, exemestane, microemulsion, SMEDDS  相似文献   

2.
AJS is the code name of an untitled novel medicative compound synthesized by the Tasly Holding Group Company (Tianjin, China) based on the structure of cinnamamide, which is one of the Biopharmaceutics Classification System (BCS) class II drugs. The drug has better antidepressant effect, achieved by acting on the 5-hydroxytryptamine receptor. However, the therapeutic effects of the drug are compromised due to its poor water solubility and lower bioavailability. Herein, a self-microemulsifying drug delivery system (SMEDDS) was developed to improve its solubility and oral bioavailability. AJS-SMEDDS formulation was optimized in terms of drug solubility in the excipients, droplet size, stability, and drug precipitation using a pseudo-ternary diagram. The pharmacokinetic study was performed in rats, and the drug concentration in plasma samples was assayed using the high-performance liquid chromatography-electrospray tandem mass spectrometry (HPLC-MS/MS) method. The optimized formulation for SMEDDS has a composition of castor oil 24.5%, Labrasol 28.6%, Cremphor EL 40.8%, and Transcutol HP 2.7% (co-surfactant). No drug precipitation or phase separation was observed from the optimized formulation after 3 months of storing at 25°C. The droplet size of microemulsion formed by the optimized formulation was 26.08 ± 1.68 nm, and the zeta potential was −2.76 mV. The oral bioavailability of AJS-SMEDDS was increased by 3.4- and 35.9-fold, respectively, compared with the solid dispersion and cyclodextrin inclusion; meanwhile, the Cmax of AJS-SMEDDS was about 2- and 40-fold as great as the two controls, respectively. In summary, the present SMEDDS enhanced oral bioavailability of AJS and was a promising strategy to orally deliver the drug.KEY WORDS: bioavailability, HPLC-MS/MS, self-microemulsifying drug delivery system, solubilization, stability  相似文献   

3.
A self-microemulsifying drug delivery system (SMEDDS) has been developed to enhance diffusion rate and oral bioavailability of valsartan. The solubility of valsartan was checked in different oils, surfactants, and cosurfactants and ternary phase diagrams were constructed to evaluate the microemulsion domain. The valsartan SMEDDS was prepared using Capmul MCM (oil), Tween 80 (surfactant), and polyethylene glycol 400 (cosurfactant). The particle size distribution, zeta potential, and polydispersity index were determined and were found to be 12.3 nm, −0.746, and 0.138, respectively. Diffusion rate of valsartan was measured by in vitro dialysis bag method using phosphate buffer pH 6.8 as diffusion media. Developed high-performance liquid chromatography method was used to determine drug content in diffusion media. Oral bioavailability of valsartan SMEDDS was checked by using rabbit model. Results of diffusion rate and oral bioavailability of valsartan SMEDDS were compared with those of pure drug solution and of marketed formulation. Diffusion of valsartan SMEDDS showed maximum drug release when compared to pure drug solution and marketed formulation. The area under curve and time showed significant improvement as the values obtained were 607 ng h/mL and 1 h for SMEDDS in comparison to 445.36 and 1.36 h for market formulation suggesting significant increase (p < 0.01) in oral bioavailability of valsartan SMEDDS.  相似文献   

4.
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.  相似文献   

5.
The objective of present investigation was to formulate self-microemulsifying drug delivery systems (SMEDDS) of tacrolimus (FK 506), a poorly water soluble immunosuppressant that exhibits low and erratic bioavailability. Solubility of FK 506 in various oils, surfactants cosurfactants and buffers was determined. Phase diagrams were constructed at different ratios of surfactant/cosurfactant (K m ) to determine microemulsion existence region. The effect of oil content, pH of aqueous phase, dilution, and incorporation of drug on mean globule size of resulting microemulsions was studied. The optimized SMEDDS formulation was evaluated for in vitro dissolution profile in comparison to pure drug and marketed formulation (Pangraf capsules). The in vivo immunosuppressant activity of FK 506 SMEDDS was evaluated in comparison to Pangraf capsules. Area of o/w microemulsion region in phase diagram was increased with increase in K m . The SMEDDS yielded microemulsion with globule size less than 25 nm which was not affected by the pH of dilution medium. The SMEDDS was robust to dilution and did not show any phase separation and drug precipitation even after 24 h. Optimized SMEDDS exhibited superior in vitro dissolution profile as compared to pure drug and Pangraf capsules. Furthermore, FK 506 SMEDDS exhibited significantly higher immunosuppressant activity in mice as compared to Pangraf capsules.  相似文献   

6.
The purpose of this research work was to formulate and characterize self-micro emulsifying drug delivery system containing exemestane. The solubility of exemestane was determined in various vehicles. Pseudo ternary phase diagram was used to evaluate the micro-emulsification existence area. SMEDDS formulations were tested for micro-emulsifying properties, and the resultant formulations loaded with exemestane (ME1, ME2, ME3, ME4 and ME5) were investigated for clarity, phase separation, globule size and shape, zeta potential, effect of various diluents and dilutions, thermodynamic and thermal stability. From the results it is concluded that increase in droplet size is proportional to the concentration of oil in SMEDDS formulation. Minor difference in the droplet size and zeta potential was observed by varying the diluents (deionized water and 0.1 N HCl) and dilutions (1:10, 1:50 and 1:100). Formulations, which were found to be thermodynamically stable (ME1, ME2, ME3 and ME4), were subjected to stability studies as per International Conference on Harmonization (ICH) guidelines. No significant variations were observed in the formulations over a period of 3 months at accelerated and long-term conditions. TEM photographs of microemulsions formulations further conformed the spherical shape of globules. Among the various SMEDDS formulations, ME4 offer the advantages of good clarity systems at high oil content and thus offer good solubilization of exemestane. Thus this study indicates that the SMEDDS can be used as a potential drug carrier for dissolution enhancement of exemestane and other lipophilic drug(s).  相似文献   

7.
Oral administration of peptide and protein drugs faces a big challenge partly due to the hostile gastrointestinal (GI) environment. Lipid-based delivery systems are attractive because they offer some protection for peptides and proteins. In this context, we prepared a special lipid-based oral delivery system: archaeosomes, made of the polar lipid fraction E (PLFE) extracted from Sulfolobus acidocaldarius, and explored its potential as an oral drug delivery vehicle. Our study demonstrates that archaeosomes have superior stability in simulated GI fluids, and enable fluorescent labeled peptides to reside for longer periods in the GI tract after oral administration. Although archaeosomes have little effect on the transport of insulin across the Caco-2 cell monolayers, the in vivo experiments indicated that archaeosomes containing insulin induced lower levels of blood glucose than a conventional liposome formulation. These data indicate that archaeosomes could be a potential carrier for effective oral delivery of peptide drugs.  相似文献   

8.
The integrated responses of the hormonal regulation of growth and stress in sunshine bass (Morone chrysops X Morone saxatilis) as regulated by feed deprivation were investigated. Groups of fish were fed 1.5% of the body weight per day or offered no feed for 4 weeks. Another group of fish was not fed for 3 weeks and feed was offered during the fourth week. Fish in each group were sampled immediately before or after a 15-min low water confinement stressor after each week of the experiment. Liver mass and liver glycogen content were decreased after one week of fasting and remained low until the end of the study. However, both recovered after a week of refeeding. Intraperitoneal fat was significantly lower after two weeks of fasting and did not recover after a week of refeeding. None of these components were affected by confinement stress. Plasma glucose in unstressed fish was generally unaffected by fasting or refeeding; however, plasma glucose increased after confinement stress in fed but not in fasted fish. The cortisol stress response was unaltered by fasting and remained robust. Plasma IGF-I generally decreased in fasted fish but was not significantly lower than fed fish until the fourth week. A week of refeeding did not restore plasma IGF-I concentrations. Plasma IGF-I concentrations were higher in confinement stressed fed fish after two and four weeks but were unchanged in the fourth week. There was no change in the plasma IGF-I concentrations in fasted or refed fish due to the stress. Liver weight and liver glycogen were essentially depleted after 2 weeks of fasting. The reduction of liver glycogen greatly reduced the glucose response to stress; however, the cortisol stress response was maintained for at least four weeks of fasting. Intraperitoneal fat was decreased very little after 4 weeks of fasting. Plasma IGF-I concentrations were reduced only after 3 weeks of fasting.  相似文献   

9.
Abstract

The increasing incidence of venous thromboembolism (VTE) in paediatric population has stimulated the development of liquid anticoagulant formulations. Thus our goal is to formulate a liquid formulation of poorly-water soluble anticoagulant, rivaroxaban (RIVA), for paediatric use and to assess the possibility of its intravenous administration in emergencies. Self-nanoemulsifying drug delivery systems (SNEDDSs) were developed and characterized. SNEDDS constituents were estimated from the saturated solubility study followed by plotting the corresponding ternary phase diagrams to determine the best self-emulsified systems. Thermodynamic stability, emulsification, dispersibility, robustness to dilution tests, in vitro dissolution, particle size, and zeta potential were executed to optimize the formulations. The optimized formulation, that composed of Capryol 90:Tween 20:PEG 300 (5:45:50), increased RIVA solubility (285.7-fold than water), it formed nanoemulsion with a particle size of 16.15?nm, PDI of 0.25 and zeta potential of ?21.8. It released 100.83?±?2.78% of RIVA after 5?min. SNEDDS was robust to dilution with oral and parenteral fluids and showed safety to human RBCs. SNEDDS showed enhanced bioavailability after oral and intravenous administration than the oral drug suspension (by 1.25 and 1.26-fold, respectively). Moreover, it exhibited enhanced anticoagulant efficacy in the prevention and treatment of carrageenan-induced thrombosis rat model.  相似文献   

10.
We investigated the effects of dietary fat energy restriction and fish oil intake on glucose and lipid metabolism in female KK mice with high-fat (HF) diet-induced obesity. Mice were fed a lard/safflower oil (LSO50) diet consisting of 50 energy% (en%) lard/safflower oil as the fat source for 12 weeks. Then, the mice were fed various fat energy restriction (25 en% fat) diets — LSO, FO2.5, FO12.5 or FO25 — containing 0, 2.5, 12.5, or 25 en% fish oil, respectively, for 9 weeks. Conversion from a HF diet to each fat energy restriction diet significantly decreased final body weights and visceral and subcutaneous fat mass in all fat energy restriction groups, regardless of fish oil contents. Hepatic triglyceride and cholesterol levels markedly decreased in the FO12.5 and FO25 groups, but not in the LSO group. Although plasma insulin levels did not differ among groups, the blood glucose areas under the curve in the oral glucose tolerance test were significantly lower in the FO12.5 and FO25 groups. Real-time polymerase chain reaction analysis showed fatty acid synthase mRNA levels significantly decreased in the FO25 group, and stearoyl-CoA desaturase 1 mRNA levels markedly decreased in the FO12.5 and FO25 groups. These results demonstrate that body weight gains were suppressed by dietary fat energy restriction even in KK mice with HF diet-induced obesity. We also suggested that the combination of fat energy restriction and fish oil feeding decreased fat droplets and ameliorated hepatic hypertrophy and insulin resistance with suppression of de novo lipogenesis in these mice.  相似文献   

11.
Various effects of temperature on heterologous alkaline polygalacturonate lyase produced in recombinant Pichia pastoris were investigated. The results indicated that PGL activity could be improved significantly by decreasing the cultivation temperature. It was reached 931 U/mL with temperature lowered to 22 °C at the beginning of induction phase, which were 2.1-fold and 2.9-fold increase compared to that at 30 and 26 °C. The mechanisms behind the temperature effect on recombinant PGL production may be ascribed to poor cell viability, decrease of intracellular adenosine phosphate levels, of AOX activity but increase of extracellular proteases activities. Our study demonstrated that cultivation at lower temperatures resulted in higher cell viability, significant improvement of PGL stability and an increase intracellular AOX activity, but a lower activity of released host proteases which possibly caused the degradation of recombinant PGL. In addition, the evidence of higher intracellular adenosine phosphate levels but lower energy charge level was provided at a lower temperature induction.  相似文献   

12.
Surmounting the constraints of limited solubilization efficiency and prime requisite of antioxidant for conventional lipid formulations, the research work explores an edge over formulation utilizing potential applicability of rice germ oil (RGO) as a multifunctional excipient. Self-microemulsifying drug delivery system (SMEDDS) of tacrolimus (TAC) was formulated with RGO, an indigenous source of gamma-oryzanol. Being the same biological source, RGO and rice bran oil (RBO) were compared and it was found that RGO have more solubilization potential for TAC (2.2-fold) as well as higher antioxidant activity (8.06-fold) than the RBO. TAC-SMEDDS was prepared using RGO/Capmul PG8 (2:3) as an oil phase, Cremophore EL as a surfactant, and Transcutol P as a cosurfactant. The approximate particle size of TAC-SMEDDS was found to be 38 nm by dynamic light scattering and 12 nm by small angle neutron scattering. The in vitro dissolution studies showed complete and rapid drug release in 30 min compared to a plain drug (<5%) and marketed capsule (<50%). AUC and C max were found to be 45.05 ± 15.64 ng h/ml and 3.91 ± 1.2 ng/ml for TAC-SMEDDS, 12.59 ± 5.54 ng h/ml and 0.48 ± 0.12 ng/ml for plain TAC, and 30.23 ± 10.34 ng h/ml and 2.31 ± 0.68 ng/ml for marketed formulation, respectively. The improved pharmacokinetic profile of TAC-SMEDDS is correlating to the dissolution results. Thus, gamma-oryzanol-enriched RGO acts as a potential multifunctional excipient for lipid formulations.  相似文献   

13.
Quercetin (QT) was formulated into a novel self-emulsifying drug delivery system (SEDDS) to improve its oral bioavailability and antioxidant potential compared to free drug. Capmul MCM was selected as the oily phase on the basis of optimum solubility of QT in oil. Tween 20 and ethanol were selected as surfactant and cosurfactant from a large pool of excipients, depending upon their spontaneous self-emulsifying ability with the selected oily phase. Pseudoternary-phase diagrams were constructed to identify the efficient self-emulsification regions in various dilution media, viz., water, pH 1.2, and pH 6.8. The ratio of 40:40:20 w/w, Capmul MCM:QT (19:1)/Tween 20/ethanol was optimized based on its ability to form a spontaneous submicrometer emulsion in simulated gastrointestinal fluids. DPPH scavenging assay showed comparable antioxidant activity of QT-SEDDS to free QT. QT-SEDDS was robust in terms of stability against short-term excursion of freeze/thaw cycles and accelerated stability for 6 months as per International Conference on Harmonisation guidelines. A fluorescent dye-loaded SEDDS formulation showed rapid internalization within 1 h of incubation with Caco-2 cells as evident by confocal laser scanning microscopy. QT-SEDDS showed a significant increase in cellular uptake by 23.75-fold in comparison with free QT cultured with Caco-2 cells. The SEDDS demonstrated ~5-fold enhancement in oral bioavailability compared to free QT suspension. The in vitro–in vivo relation between in vitro Caco-2 cell uptake and in vivo pharmacokinetics of QT-SEDDS showed a correlation coefficient of ~0.9961, as evident from a Levy plot. Finally, QT-SEDDS showed a significantly higher in vivo antioxidant potential compared to free QT when evaluated as a function of ability to combat doxorubicin- and cyclosporin A-induced cardiotoxicity and nephrotoxicity, respectively.  相似文献   

14.
Sparingly, water-soluble drugs such as candesartan cilexetil offer challenges in developing a drug product with adequate bioavailability. The objective of the present study was to develop and characterize self-microemulsifying drug delivery system (SMEDDS) of candesartan cilexetil for filling into hard gelatin capsules. Solubility of candesartan cilexetil was evaluated in various nonaqueous careers that included oils, surfactants, and cosurfactants. Pseudoternary phase diagrams were constructed to identify the self-microemulsification region. Four self-microemulsifying formulations were prepared using mixtures of oils, surfactants, and cosurfactants in various proportions. The self-microemulsification properties, droplet size, and zeta potential of these formulations were studied upon dilution with water. The optimized liquid SMEDDS formulation was converted into free flowing powder by adsorbing onto a solid carrier for encapsulation. The dissolution characteristics of solid intermediates of SMEDDS filled into hard gelatin capsules was investigated and compared with liquid formulation and commercial formulation to ascertain the impact on self-emulsifying properties following conversion. The results indicated that solid intermediates showed comparable rate and extent of drug dissolution in a discriminating dissolution medium as liquid SMEDDS indicating that the self-emulsifying properties of SMEDDS were unaffected following conversion. Also, the rate and extent of drug dissolution for solid intermediates was significantly higher than commercial tablet formulation. The results from this study demonstrate the potential use of SMEDDS as a means of improving solubility, dissolution, and concomitantly the bioavailability.  相似文献   

15.
Nanosized calcium phosphates studied as drug delivery systems are highly compatible with the various drugs like insulin, antibiotics etc. Zinc is an essential trace element that plays a crucial role in the synthesis, storage and release of insulin in a human body. Therefore, an attempt has been made to develop zinc modified calcium phosphate nanoparticles (less than 100 nm) as carriers for intestinal delivery of insulin. The insulin loaded nanoparticles were coated with pH sensitive alginate. These pH sensitive nanoparticles released insulin in the intestinal medium, and the conformation of released insulin was stable. The blood glucose level of diabetic rats came to normal on administration of the formulation. With the beneficial effect of zinc reported on diabetic patients, the present system seems to be an excellent carrier for intestinal delivery of insulin.  相似文献   

16.
The objective was to examine the effect of polyunsaturated fatty acid type (plant vs fish oil-derived n-3, compared to n-6 fatty acids in the presence of constant proportions of saturated, monounsaturated and polyunsaturated fatty acids) on obesity, insulin resistance and tissue fatty acid composition in genetically obese rats. Six-week-old fa/fa and lean Zucker rats were fed with a 10% (w/w) mixed fat diet containing predominantly flax-seed, menhaden or safflower oils for 9 weeks. There was no effect of dietary lipid on obesity, oral glucose tolerance (except t=60 min insulin), pancreatic function or molecular markers related to insulin, glucose and lipid metabolism, despite increased n-3 fatty acids in muscle and adipose tissue. The menhaden oil diet reduced fasting serum free fatty acids in both fa/fa and lean rats. These data suggest that n-3 composition does not alter obesity and insulin resistance in the fa/fa Zucker rat model when dietary lipid classes are balanced.  相似文献   

17.
目的:研究维生素E自微乳的制备工艺.方法:考察了维生素E在不同油、乳化剂、助乳化剂中的溶解情况,筛选油相、乳化剂和助乳化剂.以假三角相图中形成微乳的面积为指标,采用正交设计表对处方进行优化,确定维生素E自乳化给药系统的最佳处方.结果:微乳最佳处方:油酸乙酯:Tween-80:丙二醇的比例为3:4:3.结论:该处方自乳化区域大,自微乳化速率快,所形成的乳剂稳定.  相似文献   

18.
The effects of an oral fish oil treatment regimen on sensorimotor, blood–brain barrier, and biochemical outcomes of traumatic brain injury (TBI) were investigated in a juvenile rat model. Seventeen-day old Long-Evans rats were given a 15 mL/kg fish oil (2.01 g/kg EPA, 1.34 g/kg DHA) or soybean oil dose via oral gavage 30 min prior to being subjected to a controlled cortical impact injury or sham surgery, followed by daily doses for seven days. Fish oil treatment resulted in less severe hindlimb deficits after TBI as assessed with the beam walk test, decreased cerebral IgG infiltration, and decreased TBI-induced expression of the Mmp9 gene one day after injury. These results indicate that fish oil improved functional outcome after TBI resulting, at least in part from decreased disruption of the blood–brain barrier through a mechanism that includes attenuation of TBI-induced expression of Mmp9.  相似文献   

19.
A polygalacturonate lyase (PGL), PelA, was purified from the culture broth of Bacillus subtilis 7-3-3, with a molecular weight, optimal temperature, and pH of approximately 45 kDa, 55 °C, and 9.4, respectively. The PGL gene (pelA) was homologously overexpressed in B. subtilis 7-3-3 to increase the gene copies and enhance the PGL production. The resulting PGL activity was 2138 U mL?1 at 44 h, and the productivity reached 48.58 U (mL h)?1 through the homologous overexpression of strain B-pN-pelA in a 7.5 L fermentor, the highest PGL production compared to those reported in literature to the best of our knowledge. Crude enzyme has high PGL and PGase activity, which can remove 50.58% of pectin in unpretreatment ramie fibers at 50 °C for 4 h. Meanwhile, the enzyme system with a low level hemicellulase and almost no cellulase will further help in enhancing the efficiency of degumming besides maintaining tenacity of plant fiber. The B. subtilis B-pN-pelA shows high genetic stability and has great potential in the textile industry.  相似文献   

20.
The objective of the present investigation was to develop and evaluate self-microemulsifying drug delivery system (SMEDDS) for improving the delivery of a BCS class II antidiabetic agent, glyburide (GLY). The solubility of GLY in oils, cosurfactants, and surfactants was evaluated to identify the components of the microemulsion. The ternary diagram was plotted to identify the area of microemulsion existence. The in vitro dissolution profile of GLY SMEDDS was evaluated in comparison to the marketed GLY tablet and pure drug in pH 1.2 and pH 7.4 buffers. The chemical stability of GLY in SMEDDS was determined as per the International Conference on Harmonisation guidelines. The area of microemulsion existence increased with the increase in the cosurfactant (Transcutol P) concentration. The GLY microemulsion exhibited globule size of 133.5 nm and polydispersity index of 0.94. The stability studies indicated that GLY undergoes significant degradation in the developed SMEDDS. This observation was totally unexpected and has been noticed for the first time. Further investigations indicated that the rate of GLY degradation was highest in Transcutol P.  相似文献   

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