Enhanced oral bioavailability of curcumin via a solid lipid-based self-emulsifying drug delivery system using a spray-drying technique

In this study, a novel liquid self-emulsifying drug delivery system (SEDDS) containing curcumin was formulated and further developed into a solid form by a spray drying method using Aerosil 200 as the solid carrier. The optimum liquid SEDDS consisted of Lauroglycol Fcc, Labrasol and Transcutol HP as the oil phase, the surfactant and the co-surfactant at a weight ratio of 15.0 : 70.8 : 14.2 (w/w/w), respectively. There was no difference in droplet size between the emulsions obtained from the liquid and solid forms of SEDDS. Solid state characterization of the solid SEDDS was performed by scanning electron micrograph (SEM), differential scanning calorimetry (DSC), and X-ray powder diffraction (XRPD). The drug formulated in the solid SEDDS was quickly and completely dissolved within 5 min, both in 0.1 N HCl and phosphate buffer pH 6.8 dissolution media, whereas crude curcumin powder was significantly less dissoluble. The solid SEDDS formulation was stable for at least 3 months at 40°C with 75% relative humidity. After oral administration to rats, curcumin in the solid SEDDS resulted in significant improvement in in vivo absorption compared with that of curcumin powder. As the dose of curcumin formulated in solid SEDDS increased from 25 to 100 mg/kg, the C(max) and area under the drug concentration time curve (AUC) of curcumin were increased by 4.6 and 7.6 times, respectively. However, the over-proportional increase in the AUC in the higher dose group might be due to underestimation of AUC in the lower dose group. In conclusion, this solid SEDDS is a promising solid dosage form for poorly water-soluble curcumin.     

Systematic Development of Self-Emulsifying Drug Delivery Systems of Atorvastatin with Improved Bioavailability Potential

The aim of this study was to prepare and characterize a self-emulsifying drug delivery system (SEDDS) with a high drug load of poorly water-soluble atorvastatin for the enhancement of dissolution and oral bioavailability. Solubility of atorvastatin in oil, surfactant, and cosurfactant was determined. Pseudo-ternary phase diagrams were constructed by the aqueous titration method, and formulations were developed based on the optimum excipient combinations. A high drug load (10% w/w) was achieved with a combination of oleic acid, Tween 80, and polyethylene glycol 400, ensuring the maximum dissolution property (in the case of SES6). Effects of lipids and surfactants on physical properties of SEDDS such as in vitro emulsification efficiency in terms of self-emulsification time, emulsion droplet size, and percent transmittance were measured. Multiple regression analysis revealed that a higher amount of surfactants significantly increased dissolution of ATV while decreasing emulsion droplet size and emulsification time. About a four-fold increase in dissolution was achieved by SEDDS compared to pure ATV powder. Overall, this study suggests that dissolution and oral bioavailability of ATV could be improved by SEDDS technology.     

Dry elixir formulations of dexibuprofen for controlled release and enhanced oral bioavailability

The objective of this study was to achieve an optimal formulation of dexibuprofen dry elixir (DDE) for the improvement of dissolution rate and bioavailability. To control the release rate of dexibuprofen, Eudragit(?) RS was employed on the surface of DDE resulting in coated dexibuprofen dry elixir (CDDE). Physicochemical properties of DDE and CDDE such as particle size, SEM, DSC, and contents of dexibuprofen and ethanol were characterized. Pharmacokinetic parameters of dexibuprofen were evaluated in the rats after oral administration. The DDE and CDDE were spherical particles of 12 and 19 μm, respectively. The dexibuprofen and ethanol contents in the DDE were dependent on the amount of dextrin and maintained for 90 days. The dissolution rate and bioavailability of dexibuprofen loaded in dry elixir were increased compared with those of dexibuprofen powder. Moreover, coating DDE with Eudragit(?) RS retarded the dissolution rate of dexibuprofen from DDE without reducing the bioavailability. Our results suggest that CDDE may be potential oral dosage forms to control the release and to improve the bioavailability of poorly water-soluble dexibuprofen.     

In situ intestinal permeability and in vivo oral bioavailability of celecoxib in supersaturating self-emulsifying drug delivery system

In order to characterize the in situ intestinal permeability and in vivo oral bioavailability of celecoxib (CXB), a poorly water-soluble cyclooxygenase (COX)-2 inhibitor, various formulations including the self-emulsifying drug delivery system (SEDDS) and supersaturating SEDDS (S-SEDDS) were compared. The S-SEDDS formulation was obtained by adding Soluplus as a precipitation inhibitor to SEDDS, composed of Capryol 90 as oil, Tween 20 as surfactant, and Tetraglycol as cosurfactant (1:4.5:4.5 in volume ratio). An in situ single pass intestinal perfusion study in rats was performed with CXB-dissolved solutions at a concentration of 40 μg/mL. The effective permeability (P_eff) of CXB in the control solution (2.5 v/v% Tween 20-containing PBS) was 6.39 × 10^?5 cm/s. The P_eff value was significantly increased (P < 0.05) by the lipid-based formulation, yielding 1.5- and 2.9-fold increases for the SEDDS and S-SEDDS solutions, respectively, compared to the control solution. After oral administration of various formulations to rats at the equivalent dose of 100 mg/kg of CXB, the plasma drug level was measured by LC–MS/MS. The relative bioavailabilities of SEDDS and S-SEDDS were 263 and 355 %, respectively, compared to the CXB suspension as a reference. In particular, S-SEDDS revealed the highest C_max and the smallest T_max, indicating rapid and enhanced absorption with this formulation. This study illustrates the potential use of the S-SEDDS formulation in the oral delivery of poorly water-soluble compounds.     

Development and characterization of liquid and solid self-emulsifying drug delivery system of fexofenadine

Fexofenadine, the active metabolite of terfenadine, a well known and effective H1 receptor antagonist, is administered by the oral route. The objective of present investigation was to develop and characterize a liquid self-emulsifying drug delivery system (SEDDS) and a solid SEDDS by using bioenhancer excipients like Tween 80 and Labrasol which are known for their inhibiting action on CYP450 and P-glycoprotein pump. Solubility of fexofenadine was determined in various vehicles, including oils, surfactants and co-solvents. Various evaluation parameters (emulsification study, particle size, poly-dispersibility index, % drug release, etc.) were carried out to find out optimized liquid SEDDS formulation. Optimized liquid formulations were converted in solid SEDDS by simple and convenient physical adsorption technique. Solid SEDDS was characterized by X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Fourier transport infra-red spectroscopy. The optimized liquid SEDDS formulation contained 29 % Captex 200P/Capmul MCM C8 EP as oil, 47 % Labrasol/Tween 80 as a surfactant and 24 % Ethanol as a co-solvent. The optimized liquid and solid SEDDS showed higher drug release than pure API powder. DSC and XRD results of solid SEDDS confirmed that the drug presented in the formulation was in an amorphous state. The prepared liquid SEDDS and solid SEDDS containing bio-enhancer excipients increased the in vitro dissolution rate of fexofenadine compared to pure drug and has potential to increase bioavailability by blocking Pgp efflux pump and CYP450 hepatic metabolism.     

Enhanced oral bioavailability of etodolac by self‐emulsifying systems: in‐vitro and in‐vivo evaluation

Objectives The objective of this study was to prepare a self‐emulsifying drug delivery system (SEDDS) for oral bioavailability enhancement of a poorly water‐soluble drug, etodolac. The SEDDS formulations were optimized by evaluating their ability to self‐emulsify when introduced to an aqueous medium under gentle agitation, and by determination of the particle size of the resulting emulsion. Methods An optimized formulation of SEDDS (composed of 20% etodolac, 30% oil Labrafac WL1349, 10% Lauroglycol 90 and 40% Labrasol) was selected for bioavailability assessment in rabbits. The anti‐inflammatory effect was also determined in rats, and compared with powder drug and etodolac suspension in water (50 mg/kg). Key findings The peak plasma concentration of 16.4 ± 1.1 μg/ml appeared after 1.3 ± 0.2 h, whereas with powder drug and etodolac suspension the values were 7.5 ± 0.5 and 10.6 ± 0.7 μg/ml at 4.2 ± 0.4 and 2.4 ± 0.2 h, respectively. The AUC_0–8 of the etodolac SEDDS formulation was 2.3 times that of the pure drug and 1.4 times that of the suspension form. SEDDS formulation exhibits a 21% increase in paw thickness compared with a 39% increase on oral administration of etodolac suspension after 4 h at the same dose of the drug (20 mg/kg). Conclusions The result indicates the utility of SEDDS for the oral delivery of etodolac and potentially other lipophilic drugs.     

Role of lipid-based excipients and their composition on the bioavailability of antiretroviral self-emulsifying formulations

Abstract

The objective of this study was to develop self-emulsifying drug delivery system (SEDDS) to improve solubility and enhance the oral absorption of the poorly water-soluble drug, nevirapine. This lipid-based formulation may help to target the drug to lymphoid organs where HIV-1 virus resides mainly. The influence of the oil, surfactant and co-surfactant types on the drug solubility and their ratios on forming efficient and stable SEDDS were investigated in detail. Two SEDDS (F1 and F2) were prepared and characterized by morphological observation, droplet size and zeta potential determination, cloud point measurement and in vitro diffusion study. The influence of droplet size on the absorption from formulations with varying concentration of oil and surfactant was also evaluated from two self-emulsifying formulations. Oral bioavailability of nevirapine SEDDS was checked by using rat model. Results of diffusion rate and oral bioavailability of nevirapine SEDDS were compared with marketed suspension. The absorption of nevirapine from F1 and F2 showed 1.92 and 1.98-fold increase (p?<?0.05) in relative bioavailability, respectively, compared with that of the suspension. There was no statistical significant difference (p?<?0.05) between F1 and F2 in their AUC and C_max. This indicated that there was apparent poor correlation between the droplet size and in vivo absorption. However, nevirapine in SEDDS showed higher ex vivo stomach and intestinal permeability and in vivo absorption than the marketed suspension, suggesting that the SEDDS may be a useful delivery system for targeting nevirapine to lymphoid organs.     

Formulation development and pharmacokinetics of puerarin self-emulsifying drug delivery systems

The main purpose of this work was to prepare a self-emulsifying drug delivery system (SEDDS) for a poorly water-soluble drug, puerarin. The solubility of puerarin was determined in various oils and surfactants. Oleic acid and Tween 80 provided relatively higher solubility. The addition of propylene glycol as a cosurfactant improved the solubility of puerarin and the spontaneity of self-emulsification. A series of mixtures composed of oleic acid, propylene glycol, and Tween 80 were prepared and their self-emulsifying properties were studied. Pseudo-ternary phase diagrams were constructed to identify the efficient self-emulsification region, and the particle sizes of the resultant emulsions were determined using a laser diffraction sizer. The pharmacokinetic behaviors of three different SEDDS formulations were investigated in beagle dogs. The bioavailability of puerarin was compared using the pharmacokinetic parameters, peak plasma concentration (C(max)), time to reach peak plasma concentration (T(max)), and total area under the plasma concentration-time curve (AUC(0-infinity)). The analysis of the data showed a statistically significant difference between F2 and F4 (P < 0.01) as well as F3 and F4 (P < 0.01) with regard to the values of AUC(0-infinity) and C(max) but not between those of F2 and F3 (P > 0.05). In the case of parameter T(max), ke, no statistically significant difference (P > 0.05) among the values were observed. From these studies, a SEDDS containing oleic acid (17.5%), Tween 80 (34.5%), and propylene glycol (34.5%) (w/w) was selected as an optimized SEDDS formulation for puerarin. The data suggest the potential use of SEDDS to improve the oral absorption of puerarin.     

Bioavailability of cyclosporin A dispersed in sodium lauryl sulfate-dextrin based solid microspheres

The purpose of this work was to develop a solid dispersion system containing cyclosporin A (CsA) in order to improve the bioavailability of poorly water-soluble CsA. Solid dispersion systems that are spherical in shape (CsA-microspheres) were prepared with varying ratios of CsA/sodium lauryl sulfate/dextrin using a spray-drying technique. The effects of sodium lauryl sulfate (SLS) and dextrin on the dissolution of CsA dispersed in SLS-dextrin based solid microspheres were investigated. The bioavailability of CsA-microspheres was compared with CsA powder alone and commercial Sandimmun in dogs. SLS significantly enhanced the dissolution of CsA from microspheres, while dextrin did not affect this. The CsA-microspheres at the CsA/SLS/dextrin ratio of 1/3/1, which gave the highest dissolution rate of CsA among the formula treated, was selected as an optimal formula for oral delivery. This formula gave significantly higher blood levels, area under the drug concentration-time curve (AUC) and maximum blood concentration of drug (Cmax) of CsA in dogs compared with the CsA powder alone. The AUC, Cmax and time to reach maximum blood concentration (Tmax) of CsA with CsA-microspheres was not significantly different from those after oral administration of Sandimmun, suggesting the similar bioavailability to Sandimmun in dogs. Our study demonstrates that the CsA-microspheres prepared with SLS and dextrin, with improved bioavailability of CsA, would be useful to deliver a poorly water-soluble CsA and could be applicable to other poorly water-soluble drugs.     

Solubility enhancers for oral drug delivery

With recent progress in high throughput screening of potential therapeutic agents, the number of poorly water-soluble drug candidates has risen sharply and formulating for poorly water-soluble compounds for oral delivery now presents one of the most frequent and greatest challenges to scientists in the pharmaceutical industry. Many new drugs and potential therapeutic compounds under investigation possess high lipophilicity, poor water solubility, and low oral bioavailability. Furthermore, development of improved oral dosage forms for currently marketed drugs can also enhance their therapeutic value. Oral delivery systems designed for poorly water-soluble drugs include micelles with surfactants, microemulsions, self-emulsifying/microemulsifying drug delivery systems (SEDDS/SMEDDS), solid dispersions, microspheres and cyclodextrin inclusion complexes. These delivery systems have been shown to enhance oral bioavailability and therapeutic effects of poorly water-soluble drugs mainly by improving the poor solubility. As a consequence of extensive research, various oral delivery systems for poorly water-soluble agents are being developed in clinical phases worldwide. New formulation technologies and multidisciplinary expertise may lead to development of advanced and effective oral drug delivery systems applicable to a wide range of poorly water-soluble drugs in the near future.     

Novel piroxicam-loaded nanospheres generated by the electrospraying technique: physicochemical characterisation and oral bioavailability evaluation

To determine if a novel electrospraying technique could be applied to an oral drug delivery system for improving the solubility and oral bioavailability of poorly water-soluble piroxicam; the nanospheres were generated with drug and polyvinylpyrrolidone (PVP) using electrospraying technique; and their physicochemical properties, solubility, release and pharmacokinetics were evaluated in comparison with piroxicam powder. All nanospheres had significantly increased drug solubility and dissolution rates in comparison with the drug powder. In particular, the nanosphere composed of piroxicam and PVP at a weight ratio of 2:8 gave about 600-fold higher solubility, 15-fold higher release rate and 3-fold higher AUC in comparison to piroxicam powder, leading to significantly enhanced oral bioavailability in rats, due to the mingled effect of nanonisation along with transformation to the amorphous state. Thus, this electrospraying technique can be utilised to produce a novel oral nanosphere delivery system with enhanced solubility and oral bioavailability for poorly water-soluble piroxicam.     

Solid self-emulsifying nitrendipine pellets: Preparation and in vitro/in vivo evaluation

Objective of this study is to develop and evaluate the new solid self-emulsifying (SE) pellets of poorly soluble nitrendipine (NTD). These pellets were prepared via extrusion/spheronization technique, using liquid SEDDS (NTD, Miglyol^® 812, Cremophor^® RH 40, Tween 80, and Transcutol^® P), adsorbents (silicon dioxide and crospovidone), microcrystalline cellulose and lactose. The resulting SE pellets with 30% liquid SEDDS exhibited uniform size (800–1000 μm) and round shape, droplet size distribution following self-emulsification was nearly same to the liquid SEDDS (72 ± 16 nm and 64 ± 12 nm). The in vitro release was similar for the two SE formulations (over 80% within 30 min), both significantly higher than the conventional tablets (only 35% within 30 min). The oral bioavailability was evaluated for the SE pellets, liquid SEDDS and conventional tablets in fasted beagle dogs. AUC of NTD from the SE pellets showed 1.6-fold greater than the conventional tablets and no significant difference compared with the liquid SEDDS. In conclusion, our studies illustrated that extrusion/spheronization technique could be a useful large-scale producing method to prepare the solid SE pellets from liquid SEDDS, which can improve oral absorption of NTD, nearly equivalent to the liquid SEDDS, but better in the formulation stability, drugs leakage and precipitation, etc.     

Physicochemical and pharmacokinetic characterization of a spray-dried malotilate emulsion

Malotilate (MT) is a hepatoprotective drug administered orally. However, MT was found to be a poorly water-soluble drug with low oral bioavailability. In the present investigation, a novel spray-dried emulsion (SDE) loaded with MT was prepared, and its physicochemical properties were characterized by rheological evaluation, particle size measurement, in vitro release, and surface morphology. The pharmacokinetic study of SDE, in comparison to MT suspension with the pure MT powder homogeneously dispersed in 0.5% CMC-Na solution, was also performed in rats after a single oral dose. It was found that SDE exhibited a 2.9-fold higher peak plasma concentration (C(max)) and 2.3-fold higher area under the curve (AUC) than MT suspension.     

Self-microemulsifying drug delivery system for improving the bioavailability of huperzine A by lymphatic uptake

Huperzine A (Hup-A) is a poorly water-soluble drug with low oral bioavailability. A self-microemulsifying drug delivery system (SMEDDS) was used to enhance the oral bioavailability and lymphatic uptake and transport of Hup-A. A single-pass intestinal perfusion (SPIP) technique and a chylomicron flow-blocking approach were used to study its intestinal absorption, mesenteric lymph node distribution and intestinal lymphatic uptake. The value of the area under the plasma concentration–time curve (AUC) of Hup-A SMEDDS was significantly higher than that of a Hup-A suspension (P<0.01). The absorption rate constant (K_a) and the apparent permeability coefficient (P_app) for Hup-A in different parts of the intestine suggested a passive transport mechanism, and the values of K_a and P_app of Hup-A SMEDDS in the ileum were much higher than those in other intestinal segments. The determination of Hup-A concentration in mesenteric lymph nodes can be used to explain the intestinal lymphatic absorption of Hup-A SMEDDS. For Hup-A SMEDDS, the values of AUC and maximum plasma concentration (C_max) of the blocking model were significantly lower than those of the control model (P<0.05). The proportion of lymphatic transport of Hup-A SMEDDS and Hup-A suspension were about 40% and 5%, respectively, suggesting that SMEDDS can significantly improve the intestinal lymphatic uptake and transport of Hup-A.     

Improved intestinal absorption of a poorly water-soluble oral drug using mannitol microparticles containing a nanosolid drug dispersion

A nozzle for a spray dryer that can prepare microparticles of water-soluble carriers containing various nanoparticles in a single step was previously developed in our laboratory. To enhance the solubility and intestinal absorption of poorly water-soluble drugs, we used probucol (PBL) as a poorly water-soluble drug, mannitol (MAN) as a water-soluble carrier for the microparticles, and EUDRAGIT (EUD) as a polymer vehicle for the solid dispersion. PBL–EUD–acetone–methanol and aqueous MAN solutions were simultaneously supplied through different liquid passages of the spray nozzle and dried together. PBL–EUD solid dispersion was nanoprecipitated in the MAN solution using an antisolvent mechanism and rapidly dried by surrounding it with MAN. PBL in the dispersion vehicle was amorphous and had higher physical stability according to powder X-ray diffraction and differential scanning calorimetry analysis. The bioavailability of PBL in PBL–EUD S-100–MAN microparticles after oral administration in rats was markedly higher (14- and 6.2-fold, respectively) than that of the original PBL powder and PBL–MAN microparticles. These results demonstrate that the composite microparticles containing a nanosized solid dispersion of a poorly water-soluble drug prepared using the spray nozzle developed by us should be useful to increase the solubility and bioavailability of drugs after oral administration.     

Encapsulation of poorly soluble basic drugs into enteric microparticles: a novel approach to enhance their oral bioavailability

Poorly water soluble basic drugs are very sensitive to pH changes and following dissolution in the acidic stomach environment tend to precipitate upon gastric emptying, which leads to compromised or erratic oral bioavailability. In this work, we show that the oral bioavailability of a model poorly soluble basic drug (cinnarizine) can be improved by drug encapsulation within highly pH-responsive microparticles (Eudragit L). The latter was prepared by emulsion solvent evaporation which yielded discrete spherical microparticles (diameter of 56.4 ± 6.8 μm and a span of 1.2 ± 0.3). These Eudragit L (dissolution threshold pH 6.0) microparticles are expected to dissolve and release their drug load at intestinal conditions. Thus, the enteric microparticles inhibited the in vitro release of drug under gastric conditions, despite high cinnarizine solubility in the acidic medium. At intestinal conditions, the particles dissolved rapidly and released the drug which precipitated out in the dissolution vessel. In contrast, cinnarizine powder showed rapid drug dissolution at low pH, followed by precipitation upon pH change. Oral dosing in rats resulted in a greater than double bioavailability of Eudragit L microparticles compared to the drug powder suspension, although C_max and T_max were similar. The higher bioavailability with microparticles contradicts the in vitro results. Such an example highlights that although in vitro results are an indispensable tool for formulation development, an early in vivo assessment of formulation behaviour can provide better prediction for oral bioavailability.     

Lipophilic Salts and Lipid-Based Formulations for Bridging the Food Effect Gap of Venetoclax

Lipid based formulations (LBF) have shown to overcome food dependent bioavailability for some poorly water-soluble drugs. However, the utility of LBFs can be limited by low dose loading due to a low drug solubility in LBF vehicles. This study investigated the solubility and drug loading increases in LBFs using lipophilic counterions to form lipophilic salts of venetoclax. Venetoclax docusate was formed from venetoclax free base and verified by ¹H NMR. Formation of stable venetoclax-fatty acid associations with either oleic acid or decanoic acid were attempted, however, the molecular associations were less consistent based on ¹H NMR. Venetoclax docusate displayed a up to 6.2-fold higher solubility in self-emulsifying drug delivery systems (SEDDS) when compared to the venetoclax free base solubility resulting in a higher dose loading. A subsequent bioavailability study in landrace pigs demonstrated a 2.5-fold higher bioavailability for the lipophilic salt containing long chain SEDDS compared to the commercially available solid dispersion Venclyxto® in the fasted state. The bioavailability of all lipophilic salt SEDDS in the fasted state was similar to Venclyxto® in the fed state. This study confirmed that lipophilic drug salts increase the dose loading in LBFs and showed that lipophilic salt-SEDDS combinations may be able to overcome bioavailability limitations of drugs with low inherent dose loading in lipid vehicles. Furthermore, the present study demonstrated the utility of a LBF approach, in combination with lipophilic salts, to overcome food dependent variable oral bioavailability of drugs.     

Eplerenone nanocrystals engineered by controlled crystallization for enhanced oral bioavailability

Poor aqueous solubility of eplerenone (EPL) is a major obstacle to achieve sufficient bioavailability after oral administration. In this study, we aimed to develop and evaluate eplerenone nanocrystals (EPL-NCs) for solubility and dissolution enhancement. D-optimal combined mixture process using Design-Expert software was employed to generate different combinations for optimization. EPL-NCs were prepared by a bottom-up, controlled crystallization technique during freeze-drying. The optimized EPL-NCs were evaluated for their size, morphology, thermal behavior, crystalline structure, saturation solubility, dissolution profile, in vivo pharmacokinetics, and acute toxicity. The optimized EPL-NCs showed mean particle size of 46.8 nm. Scanning electron microscopy revealed the formation of elongated parallelepiped shaped NCs. DSC and PXRD analysis confirmed the crystalline structure and the absence of any polymorphic transition in EPL-NCs. Furthermore, EPL-NCs demonstrated a 17-fold prompt increase in the saturation solubility of EPL (8.96 vs. 155.85 µg/mL). The dissolution rate was also significantly higher as indicated by ∼95% dissolution from EPL-NCs in 10 min compared to only 29% from EPL powder. EPL-NCs improved the oral bioavailability as indicated by higher AUC, C_max, and lower T_max than EPL powder. Acute oral toxicity study showed that EPL-NCs do not pose any toxicity concern to the blood and vital organs. Consequently, NCs prepared by controlled crystallization technique present a promising strategy to improve solubility profile, dissolution velocity and bioavailability of poorly water-soluble drugs.     

自微乳化给药系统增加索拉非尼的口服吸收生物利用度

目的:为了增加难溶性药物索拉非尼(Sorafenib)的口服吸收,本研究制备索拉非尼自微乳化给药系统并测定其口服相对生物利用度。方法:以油酸乙酯(20%,w/w)为油相,聚山梨酯-80(48%,w/w)为主要乳化剂,聚乙二醇400(16%,w/w)和乙醇(16%,w/w)为助乳化剂制备索拉非尼自微乳化给药系统,以大鼠为实验动物测定其口服相对生物利用度。结果:自微乳化给药系统中索拉非尼的终浓度为20 mg.mL-1。该制剂乳化后粒径为20～25 nm,并可在去离子水,生理盐水及5%葡萄糖溶液中稳定存在8 h。与索拉非尼混悬液相比,自微乳化给药系统可以显著增加索拉非尼的血药浓度-时间曲线下面积(AUC0～72 h),峰浓度(Cmax)和平均滞留时间(MRT),降低清除率(CL)。尤其是与口服混悬液相比,其相对生物利用度提高约25倍。结论:索拉非尼自微乳化给药系统可以显著提高索拉非尼的口服吸收相对生物利用度,有望开发成为增加其口服吸收的药物制剂。     

Development of novel ibuprofen-loaded solid dispersion with improved bioavailability using aqueous solution

To develop a novel ibuprofen-loaded solid dispersion with enhanced bioavailability, various ibuprofen-loaded solid dispersions were prepared with water, HPMC and poloxamer. The effect of HPMC and poloxamer on aqueous solubility of ibuprofen was investigated. The dissolution and bioavailability of solid dispersion in rats were then evaluated compared to ibuprofen powder. When the amount of carrier increased with a decreased in HPMC/poloxamer ratio, the aqueous solubility of ibuprofen was elevated. The solid dispersion composed of ibuprofen/HPMC/poloxamer at the weight ratio of 10:3:2 improved the drug solubility approximately 4 fold. It gave significantly higher initial plasma concentration, AUC and Cmax of drug than did ibuprofen powder in rats. The solid dispersion improved the bioavailability of drug about 4-fold compared to ibuprofen powder. Thus, this ibuprofen-loaded solid dispersion with water, HPMC and poloxamer was a more effective oral dosage form for improving the bioavailability of poor water-soluble ibuprofen.