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Introducción: el estradiol es una hormona esteroide sexual femenina usada ampliamente como terapia hormonal que presenta una baja biodisponibilidad, debido a su baja solubilidad acuosa y a su alta hidrofobicidad, perteneciendo a la clase II del sistema de clasificación de biofarmacéutica. Objetivos: diseñar y caracterizar un sistema de entrega de fármacos autoemulsificable (SEDDS) para el fármaco estradiol por pruebas fisicoquímicas con el fin de obtener la relación óptima que permitiera mejorar su solubilidad acuosa, velocidad de disolución y potencialmente su biodisponibilidad. Método: estudios de solubilidad en diferentes solventes, diagramas de fases pseudoternarios constituidos por aceites, tensioactivos, cotensioactivos y agua permitieron reconocer las diferentes regiones de formación de SEDDS e identificar los porcentajes de excipientes que conducen a la formación de soluciones isotrópicas; las formulaciones resultantes fueron caracterizadas en tiempo de autoemulsificación, robustez a la dilución, punto de nube y perfil de disolución en capsula dura. Resultados: las formulaciones que contenían Capmul MCM®, Kolliphor® RH40 y Transcutol®, tuvieron un tiempo de autoemulsificación de aproximadamente 1 min; fueron estables en tres distintos pH (1,2; 4,5 y 7,2), en diferentes volúmenes de dilución, exhibiendo una apariencia transparente, ligeramente azulada, sin precipitados, o separación de fases, puntos de nube mayores en comparación de las formulaciones que contenían Gelucire® 44/14. Conclusiones: las estrategias de caracterización empleadas en el desarrollo de esta investigación demostraron ser eficientes para la selección adecuada de excipientes y su proporción óptima para el diseño eficaz de un sistema de entrega de fármaco autoemulsificable (SEDDS).
SUMMARY Introduction: Estradiol is a female sex steroid hormone widely used as hormonal therapy that has low bioavailability, due to its low aqueous solubility and high hydro-phobicity, belonging to class II of the Biopharmaceutical Classification System. Aim: To design and characterize a self-emulsifying drug delivery system (SEDDS) for the drug estradiol by physicochemical tests to obtain the most optimal ratio that would improve its aqueous solubility, dissolution rate, and potentially its bioavailability. Method: Solubility studies in different solvents; pseudo ternary phase diagrams made up of oils, surfactants, co-surfactants, and water, allowed to recognize the different regions of SEDDS formation and identify the percentages of excipients that lead to the formation of isotropic solutions; The resulting formulations were characterized in autoemulsification time, robustness to dilution, cloud point and dissolution profile in a hard capsule. Results: The formulations containing Capmul MCM®, Kolliphor® RH40, and Transcutol®, had an autoemulsification time of approximately 1 minute; were stable at three different pHs (1.2, 4.5 and 7.2), at different dilution volumes, exhibiting a transparent, slightly bluish appearance, without precipitates, or phase separation, higher cloud points compared to the formulations containing Gelucire® 44/14. Conclusions: The characterization strategies used in the development of this research proved to be efficient for the adequate selection of excipients and their optimal ratio for the effective design of a self-emulsifying drug delivery system (SEDDS).
Introdução: o estradiol é um hormônio esteroide sexual feminino amplamente utilizado como terapia hormonal que apresenta baixa biodisponibilidade devido à sua baixa solubilidade aquosa e alta hidrofobicidade, pertencente à classe II do sistema de classificação biofarmacêutica. Objetivos: projetar e caracterizar um sistema de liberação de drogas autoemulsificante (SEDDS) para o fármaco estradiol por meio de testes físico-químicos a fim de obter a proporção ideal que melhore sua solubilidade aquosa, taxa de dissolução e potencialmente sua biodisponibilidade. Método: estudos de solubilidade em diferentes solventes, diagramas de fases pseudoternários compostos por óleos, tensoativos, cotensoativos e água permitiram reconhecer as diferentes regiões de formação de SEDDS e identificar as porcentagens de excipientes que levam à formação de soluções isotrópicas; as formulações resultantes foram caracterizadas quanto ao tempo de autoemulsificação, robustez à diluição, ponto de turvação e perfil de dissolução da cápsula dura. Resultados: as formulações contendo Capmul MCM®, Kolliphor® RH40 e Transcutol®, tiveram um tempo de autoemulsificação de aproximadamente 1 min; foram estáveis em três diferentes pH's (1,2; 4,5 e 7,2), em diferentes volumes de diluição, apresentando aspecto transparente, levemente azulado, sem precipitados ou separação de fases, pontos de turvação mais elevados em relação às formulações contendo Gelucire® 44/14. Conclusões: as estratégias de caracterização utilizadas no desenvolvimento desta pesquisa mostraram-se eficientes para a seleção adequada de excipientes e sua proporção ideal para o desenho eficaz de um sistema de liberação de fármacos autoemulsificante (SEDDS).
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The drug formulation design of self-emulsifying drug delivery systems (SEDDS) often requires numerous experiments, which are time- and money-consuming. This research aimed to rationally design the SEDDS formulation by the integrated computational and experimental approaches. 4495 SEDDS formulation datasets were collected to predict the pseudo-ternary phase diagram by the machine learning methods. Random forest (RF) showed the best prediction performance with 91.3% for accuracy, 92.0% for sensitivity and 90.7% for specificity in 5-fold cross-validation. The pseudo-ternary phase diagrams of meloxicam SEDDS were experimentally developed to validate the RF prediction model and achieved an excellent prediction accuracy (89.51%). The central composite design (CCD) was used to screen the best ratio of oil-surfactant-cosurfactant. Finally, molecular dynamic (MD) simulation was used to investigate the molecular interaction between excipients and drugs, which revealed the diffusion behavior in water and the role of cosurfactants. In conclusion, this research combined machine learning, central composite design, molecular modeling and experimental approaches for rational SEDDS formulation design. The integrated computer methodology can decrease traditional drug formulation design works and bring new ideas for future drug formulation design.
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Objective: To investigate the effect of citronellol (citronellol, CT) on the proliferation of HEp-2 and MCF-7 cells, and prepare CT self-emulsifying drug delivery system (CT-SMs). Its antitumor activity and cell uptake ability of HEp-2 cells in vitro was evaluated. Methods: The effect of CT on the cell proliferation of HEp-2 and MCF-7 were investigated by MTT assay. The pseudo- ternary phase diagram method was used to optimize the formulation of CT-SMs, and the appearance morphology, mean particle size, and Zeta potential were characterized. The effect of CT-SMs on the proliferation of HEp-2 cells was detected by MTT assay and cellular uptake was determined by fluorescence inversion microscopy and flow cytometry. Results: After a certain concentration of CT treatment, MCF-7 cells proliferation was not affected, and the difference was not statistically significant (P > 0.05 compared with the control group), while the proliferative capacity of HEp-2 cells was significantly inhibited (P < 0.05 compared with the control group) in a dose-time dependent manner. The best prescription for CT-SMs was as following: Km (emulsifier:co-emulsifier) was Kolliphor® HS 15:absolute ethanol = 7:3, CT:Km = 3:7, the mean particle size was (354.0 ± 9.5) nm, the appearance was round and spherical with uniform distribution, and the Zeta potential was (-13.4 ± 0.3) mV. The results of cellular uptake experiments showed that the intake of CT-SMs (545.70 ± 11.56) was higher than that of CT (230.00 ± 17.76) in HEp-2 cells treating the same concentration of CT-SMs and CT. Conclusion: CT-SMs could significantly inhibit the proliferation of HEp-2 cells. In this study, CT-SMs were successfully prepared by dropping water method and the quality of CT-SMs was stable and controllable.
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RESUMEN El ibuprofeno es uno de los fármacos más utilizados e indicado para terapias antiinflamatorias, dolor, entre otras patologías. Sin embargo, este fármaco presenta una baja y errática biodisponibilidad, debido a la pobre solubilidad acuosa intrínseca del mismo, por lo cual esta categorizado como clase II en el sistema de clasificación biofarmacéutica. El objetivo de este trabajo fue desarrollar, diseñar y evaluar un sistema de entrega de fármaco autoemulsificable (SEDDS) para mejorar la solubilidad y velocidad de disolución de ibuprofeno. Aceites, cosolventes, tensioactivos y portadores porosos fueron evaluados por su capacidad de mejorar la solubilidad del ibuprofeno, habilidad de autoemulsificación, robustez en diferentes pH y capacidad de adsorción. El aceite de coco, Tween 80 y propilenglicol lograron un aumento significativo de la solubilidad acuosa del ibuprofeno en un tiempo de autoemulsificación menor a 2 minutos. Neusilin US2® fue seleccionado como portador, dando como resultado un pequeño granulo de excelente fluidez, que permitió obtener comprimidos que cumplieron satisfactoriamente las pruebas de control de acuerdo con las especificaciones establecidas. Los SEDDS líquidos y sólidos son una alternativa de formulación ventajosa y prometedora para mejorar la solubilidad de fármacos pobremente solubles de acuerdo al sistema de clasificación biofarmacéutica, a través de sus propiedades de solubilización.
SUMMARY Ibuprofen is one of the most used drugs and it's indicated for anti-inflammatory therapies and pain, among other pathologies. However, this drug has a low and erratic bioavailability, due to its poor aqueous intrinsic solubility, which is categorized as class II in the Biopharmaceutical Classification System. The objective of this work was to develop, design and evaluate a self-emulsifying drug delivery system (SEDDS) to improve the solubility and dissolution rate of ibuprofen. Oils, co-solvents, surfactants and carriers were evaluated for their ability to improve the solubility of ibuprofen, self-emulsification ability, robustness at different pH levels and adsorption capacity. Coconut oil, Tween 80 and propylene glycol achieved a significant increase in the aqueous solubility of ibuprofen in a self-emulsification time of less than 2 minutes. Neusilin US2® was selected as carrier, resulting in a small granule of excellent fluidity, which allowed to obtain tablets that satisfactorily fulfilled the control tests according to the established specifications. The liquid and solid SEDDS are an advantageous and promising formulation alternative to improve the solubility of poorly soluble drugs according to the biopharmaceutical classification system, through their solubilization properties.
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Objective:To prepare self-emulsifying carrier system which was suitable for three Chinese medicinal ingredients(baicalein,berberine and allicin),and investigate transdermal absorption effect in vitro of these three self-emulsifying preparations. Method:The optimum formulation and dosage were screened by the saturated solubility method,pseudo-ternary phase diagram method and orthogonal experiment.Transdermal absorption test in vitro was carried out with excised rats skin and Franz diffusion cell.The cumulative penetration amounts of baicalein,berberine and allicin in the identical self-emulsifying system were determined by HPLC and compared with baicalein powder,berberine powder and allicin powder,respectively. Result:The optimum formulation was ethyl oleate-cremophor RH40-polyethylene glycol(PEG)400.The self-emulsifying preparation had a suitable particle size with a relatively regular spherical shape.At 10 h of transdermal absorption,the transdermal rates of baicalein,berberine and allicin in identical self-emulsifying system were 6.898 6,7.600 4,190.040 μg·cm-2·h-1,the cumulative penetration amounts of them were 71.38,85.54,1 795.16 μg·cm-2,respectively. Conclusion:The self-emulsifying carrier system is prepared successfully,which can be used by different kinds of Chinese medicinal ingredients,and the transdermal absorption effect in vitro of these self-emulsifying preparations is good,which can provide experimental basis for the preparation and transdermal absorption of self-emulsifying preparation of Chinese herbal compound.
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Objective: To optimize a self-emulsifying drug delivery system (SEDDS) formulation for psoralen and isopsoralen (PSO and IPSO) isolated from Psoraleae Fructus. Methods: A D-optimal design was used to investigate the influence of oil percentage, surfactant percentage and cosurfactant percentage on several properties of SEDDS including particle size, polydispersity, equilibrium solubility, in situ intestine absorption rate and intestinal permeability. Furthermore, the desirability function approach was applied to obtain the optimal formulation for the system. Results: The oil percentage, surfactant percentage and cosurfactant percentage were optimized to be 53.6%, 35.7% and 10.7%, respectively, which means the model is available. Conclusions: The D-optimal design is valuable to optimize the SEDDS formulation and understand formulation compositions’ functions on SEDDS properties.
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Objective: To optimize the formulation of the self-emulsifying drug delivery system of total saponins of Sanguisorba officinalis and evaluate its characteristics. Methods: The formulation and its proportion of the self-emulsifying drug delivery system of total saponins of S. officinalis were optimized based on the solubility tests, formula compatibility, microemulsion area in the ternary phase diagram and D-optimal mixing experiment design. The dosage of oil phase, surfactant and co-surfactant were investigated by drug loading, particle size, and polydispersity index. The appearance, particle size, polydispersity index, Zeta potential, and in vitro release of preparation were finally evaluated. Results: The ratio of oil phase, surfactant, and co-surfactant was 0.25: 0.45:0.30. The drug loading was 23.93 mg/g, the average particle size was (207.92 ± 2.13) nm and the zeta potential was (38.84 ± 0.18) mV. The release of SEDDS was superior to the bulk drug apparently. Conclusion: The self-emulsifying drug delivery system of total saponins of S. officinalis was established. The technology was feasible and the quality was stable.
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Objective To prepare oxymatrine (OMT) phospholipid complex (PC) self-emulsifying drug delivery system (OMT-PC- SEDDS), and evaluate its quality and release in vitro. Methods The emulsifiers, co-emulsifiers and ratio of emulsifier to co-emulsifier (Km) were selected through the pseudo-ternary phase diagram method, using emulsified area as selection index, investigation of oil phase by solubility was determined to optimize the prescription. The appearance, average particle diameter, self-emulsification time, in vitro release characteristics, and stability of OMT-PC-SEDDS were evaluated. Results The optimum prescription of OMT-PC-SEDDS was emulsifier Kolliphor HS 15 and co-emulsifier ethanol mass ratio of 2:1, the mass ratio of medium chain triglyceride (MCT) to the total mass of Kolliphor HS 15 and ethanol was 2:8. The appearance of OMTPC-SEDDS was translucent clear liquid with good stability. OMT-PC-SEDDS diluted with water to form milky and pale blue emulsion. The emulsion was observed to be spherical by transmission electron microscopy and distributed evenly with average particle size of (355.00 ± 19.50) nm and Zeta potential of (-12.80 ± 0.66) mV. In pH 6.8 phosphate buffer, the in vitro release, the in vitro release of OMT, OMT-PC, and OMT-PC-SEDDS respectively reached 93.84%, 88.39%, and 88.61% at 4 h. Conclusion The prepared OMT-PC-SEDDS by optimum formulation of this study has a good particle size and good stability.
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Objective: To explore the intestinal absorption characteristics of tanshinone components self emulsifying drug delivery system (SEDDS). Methods: In situ single-pass perfusion method was used to investigate the absorption characteristics of cryptonshinone, tanshinone I, and tanshinone IIA in rats. The absorption parameters (Ka, Papp) of cryptotanshinone, tanshinone I, and tanshinone IIA were used as indicators to study their optimum absorption site among duodenum, jejunum, ileum, and colon. The effects of verapamil hydrochloride (P-glycoprotein inhibitor, P-gp inhibitor), probenecid (multi-drug resistant protein MRP2), and 2, 4-dinitrophenol (energy inhibitor) on the absorption of cryptonshinone, tanshinone I, and tanshinone IIA were also studied, as well as the effects of their different concentration. Results: Cryptonshinone, tanshinone I, and tanshinone IIA could be absorbed at all four intestinal segments, and the optimum absorption site was the upper segment of small intestine. The absorption of cryptotanshinone and tanshinone I were concentration-dependent at experimental concentration levels (1.05-4.19 mg/L and 1.22-5.56 mg/L), while tanshinone IIA was not affected obviously by its concentrations (2.43-11.12 mg/L). Verapamil hydrochloride had no significant influence on the absorption of cryptotanshinone or tanshinone I, while the absorption of tanshinone IIA was improved remarkably. Probenecid increased the absorption of cryptonshinone and tanshinone I apparently, while had no obvious effect on that of tanshinone IIA. 2,4-Dinitrophenol could decrease the absorption of cryptonshinone, tanshinone I, and tanshinone IIA apparently. Conclusion: Cryptonshinone and tanshinone I are supposed to be the substrate of MRP2 instead of P-gp. Tanshinone IIA is supposed to be the substrate of P-gp, instead of MRP2. The energy participated in the absorption of cryptonshinone, tanshinone I, and tanshinone IIA. Active absorption maybe also involved in the absorption of cryptonshinone, tanshinone I, and tanshinone IIA.
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Objective To optimize the formulation of essential oil of Alpiniae zerumbet self-emulsifying drug delivery system (EOFAZ-SEDDS) and evaluate its pharmacological properties. Methods The emulsifiers, co-emulsifiers and ratio of emulsifier to co-emulsifier (Km) were selected through the pseudo-ternary phase diagram method, using emulsified area as selection index, and determine the optimal prescription. The appearance, particle diameter, self-emulsification efficiency, and stability were evaluated. Results The optimal SEDDS was composed of volatile oil (60%), Kolliphor HS 15 (20%), and anhydrous ethanol (20%). The appearance of EOFAZ-SEDDS was translucent diluted-yellow solution. EOFAZ-SEDDS diluted with water to form milky and pale blue emulsion with a particle size of (171.67 ± 7.64) nm and Zeta potential of (-11.51 ± 1.22) mV. The emulsion was observed to be spherical by transmission electron microscopy and distributed evenly. The self-emulsifying time of EOFAZ-SEDDS in hydrochloric acid (0.1 mol/L) was short. With the increase of the volume of medium, the self-emulsifying time was prolonged. The precipitation and delamination of EOFAZ-SEDDS were not observed within 24 h after self-emulsifying, and no stratification was observed after 30 min centrifugation. Conclusion The EOFAZ-SEDDS prepared by optimum formulationthe of this study has a good particle size and good stability.
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Nevirapine ( NVP) is the first-generation non-nucleoside reverse transcriptase inhibitor, which is a front-line drug for the treatment of AIDS and the prevention of mother-to-child transmission of HIV-1. NVP is with poor solubility and low bioavailability. With the development of new dosage forms, such as solid dispersion, self-emulsifying, microparticles, micelles, sustained-release tab-lets and floating microspheres, the bioavailability of NVP can be increased and the adverse reactions can be decreased. Research pro-gress in the new dosage forms of NVP at home and abroad was reviewed through searching literatures in order to provide basis for the development of new dosage forms of NVP.
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Objective:To prepare total ginkgo flavonoid self-emulsifying drug delivery system(TGF-SMDDS)and estimate its char-acteristics in vitro. Methods:The formula of TGF-SMDDS was optimized based on the solubility tests,formula compatibility and microe-mulsion area in the pseudo ternary phase diagram. The appearance,morphology,particle size,zeta potential and in vitro dissolution of TGF-SMDDS were investigated. Results:The formula was composed of oleoyl macrogolglycerides as the oil phase,Tween-80 as the sur-factant and XCF as the co-surfactant. The ratio of oil phase,surfactant and co-surfactant was 10 ∶ 6 ∶ 4. The drug loading was 10. 0 mg· g -1 . After mixed with water,TGF-SMDDS was formed a clear and transparent microemulsion with homogeneous small spheres as seen un-der a transmission electron microscope. The particle size and zeta potential of TGF-SMDDS was(87. 4 ±26. 7)nm and( -13. 1 ±1. 5) mV,respectively. The accumulative dissolution of TGF-SMDDS in pH1. 2 hydrochloric acid solution was(96. 1 ±4. 8)% in 45 min. Con-clusion:The TGF-SMDDS can significantly enhance the dissolution of TGF in vitro,which may be a potential effective preparation for TGF.
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Objective:To develop an HPLC method for determining the total ginkgo flavonoid in self-emulsifying drug delivery sys-tem. Methods:Effective chromatographic separation was achieved using a phenomenex C18 column (250 mm × 4. 6 mm, 5 μm) with a mobile phase composed of methanol and water (0.4% phosphoric acid) with the ratio of 50 ∶50 (v/v). The mobile phase was pumped using an isocratic HPLC system at a flow rate of 1. 0 ml·min-1 , the detection wavelength was 360 nm and the column temper-ature was 30 ℃. Results:The three components in the total ginkgo flavonoid were well separated by the proposed method. The linear relationship between the peak area and the concentration was promising within the range of 2. 0-40. 0 μg·ml-1 for quercetin, 3. 0-60. 0 μg·ml-1 for kaempferide and 2. 0-40. 0 μg·ml-1 for isorhamnetin. The mean recovery of quercetin, kaempferide and isorham-netin was 98. 4%, 99. 7% and 100. 5% with RSD of 0. 92%,0. 62% and 1. 24% (n=9), respectively. Conclusion:The method is specific and stable in the determination of total ginkgo flavonoid in self-emulsifying drug delivery system.
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The emerging trends in the combinatorial chemistry and drug design have led to the development of drug candidates with greater lipophilicity, high molecular weight and poor water solubility. Majority of the failures in new drug development have been attributed to poor water solubility of the drug. Issues associated with poor solubility can lead to low bioavailability resulting in suboptimal drug delivery. About 40% of drugs with market approval and nearly 90% of molecules in the discovery pipeline are poorly water-soluble. With the advent of various insoluble drug delivery technologies, the challenge to formulate poorly water soluble drugs could be achieved. Numerous drugs associated with poor solubility and low bioavailabilities have been formulated into successful drug products. Several marketed drugs were reformulated to improve efficacy, safety and patient compliance. In order to gain marketing exclusivity and patent protection for such products, revitalization of poorly soluble drugs using insoluble drug delivery technologies have been successfully adopted by many pharmaceutical companies. This review covers the recent advances in the field of insoluble drug delivery and business prospects.
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The self-microemulsion formulation of potassium dehydroandrographolidi succinas (PDS) has been optimized and the performance in vitro has been evaluated preliminary. Kinds of prescription accessories were screened by solubility based on the emulsifying result and efficiency, particle size of emulsions. The optimal formulation composition and compatibility proportion were determined by orthogonal design and pseudo-ternary phase diagrams. The appearance, particle size, Zeta potential and stability of this formulation were also investigated. The optimized prescription of PDS was 10% MCT, 40% Tween-20 and 50% glycerol. It can spontaneously form a transparent pale blue opalescent emulsion with emulsification time 31.27 s, particle size 37.1 nm, Zata potential -17.4 mV and good stability.
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Objective: To optimize the formulation of ginsenoside Rg3 self-emulsifying drug delivery by Box-Behnken experimental design (BBD) and evaluate its quality. Methods: Formulations were optimized using design of experiments by employing a 3-factor, 3-level BBD. Independent variables studied were the emulsifier, co-emulsifier, and the oil phase. The dependent variables were drug loading and average particle size. Through the BBD software, the response surface plots were drawn and the polynomial of influence of each factor index was obtained. Finally the formula optimization was obtained and the efficiency, droplet size, and dissolution rate of self-emulsifying drug delivery were investigated. Results: Optimum prescription was as follows: emulsifier [RH-400-Triton X-100 (1∶1)], co-emulsifier (isopropanol), and the oil phase (ethyl oleate). The optimum proportion was 3∶1.475∶0.5. The optimized ginsenoside Rg3 self-emulsifying drug delivery could fully emulsify in 5 min and the average drug loading was 917.53 μg/mL, average particle size was 111.6 nm. The dissolution degree in vitro of the formulations showed that the release rate and level were apparently superior to the conventional capsules. Conclusion: The observed responses are in close agreement with the predicted values of the mathematic models, and the BBD is suitable for optimizing ginsenoside Rg3 self-microemulsifying drug delivery.
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The purpose of present study was aimed at developing self emulsifying drug delivery system in liquid and then in pellet form that would result in improved solubility, dissolution and permeability of the poorly water soluble drug carvedilol. Pellets were prepared using extrusion-spheronization technique incorporating liquid SEDDS (carvedilol, capmul MCM EP, cremophore EL, tween 20, propylene glycol), adsorbents ( and crospovidone), microcrystalline cellulose and binder (povidone K-30). Ternary phase diagram was constructed to identify different oil-surfactant-cosurfactant mixtures according to the proportion of each point in it. The optimal CAR-SEDDS pellets showed a quicker redispersion with a droplet size of the reconstituted microemulsion being 160.47 nm, which was almost unchanged after solidification. SEM analysis confirmed good spherical appearance of solid pellets; DSC and XRD analysis confirmed that there was no crystalline carvedilol in the pellets. Pellets were then capable of transferring lipophilic compounds into the aqueous phase and significantly enhancing its release with respect to pure drug.
O propósito do presente estudo foi desenvolver um sistema líquido de liberação de fármacos auto emulsificante e, então, na forma de pélete, que poderia resultar em aprimoramento da solubilidade, da dissolução e permeabilidade do fármaco carvedilol, pouco solúvel em água. Os péletes foram preparados utilizando-se a técnica de extrusão-esferonização, incorporando líquido SEDDS (carvedilol, capmul MCM EP, Cremofor EL, Tween 20, propileno glicol), adsorventes (e crospovidona), celulose microcristallina e ligante (povidona K-30). O diagrama de fase ternário foi construído para identificar as misturas diferentes de óleo-tensoativo-co-tensoativo, de acordo com a proporção em cada ponto delas. Os péletes CAR-SEDDS mostraram redispersão mais rápida, com tamanho de gota da microemulsão reconstituída de 160,47 nm, que se mostrou quase inalterada após a solidificação. A análise por SEM confirmou a aparência esférica dos péletes sólidos. Análise por DSC e XRD confirmou que não havia carvedilol cristalino nos péletes. Estes foram, então capazes de transferir os compostos lipofílicos para a fase aquosa, aumentando, significativamente, sua liberação em relação ao fármaco puro.
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Chemistry, Pharmaceutical , Drug Implants , Emulsifying Agents , Emulsifying Agents/analysisABSTRACT
About 40% of the drug candidates have poor water solubility due to their low bioavailability. Self-emulsifying drug delivery systems (SEDDs) are mixtures of oils, surfactants and co-surfactants, which efficiently improve dissolution and bioavalabilty of sparingly soluble drugs by rapid self-emulsification. SEDDs belongs to lipid formulations, and size ranges from 100nm (SEDDs) to less than 50nm (SMEDDs). Lipophilic drugs can be dissolved in such systems, enabling them to be administered as a unit dosage form for per-oral administration. When such system is released in the lumen of the gastrointestinal tract, it disperses to form a micro/nano emulsion with the aid of GI fluid. These leads to solubilisation of drug that can subsequently be absorbed by lymphatic pathways, by passing the hepatic first pass effect.
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Nanoemulsions are submicron sized emulsion that is under extensive investigation as drug carriers for improving the delivery of therapeutic agents. These are by far the most advanced nanoparticle systems for the systemic delivery of active pharmaceutical for controlled drug delivery and targeting. These are the thermodynamically stable isotropic system in which two immiscible liquid (water and oil) are mixed to form a single phase by means of an appropriate surfactants or it mixes with a droplet diameter approximately in the range of 0.5-100 μm. Nanoemulsion droplet size falls typically in the range of 20-200 nm and shows a narrow size distribution. Nanoemulsion show great promise for the future of cosmetics, diagnostics, drug therapies and biotechnologies. Thus the aim of this review is focused on nanoemulsion advantage and disadvantage, various methods of preparation, characterization techniques and the various applications of sub micron size emulsion in different areas such as various route of administration, in chemotherapy, in cosmetic, etc.
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Objective To explore self-emulsifying particle size characterization methods and compare the regularity of various methods. Methods By setting the clarity level of turbidity standard solution, with two less soluble drugs-diterpene lactone compounds Chuanhuning and dihydropyridine drug nifedipine as model drugs, 10-12 clarity level prescriptions were selected from six different ternary phase diagram. Laser particle size scanner was used to determine the particle size, and UV-visible spectrophotometry to determine its absorbance. Three methods of particle size characterization rules were compared by drawing charts. Results There was a positive correlationship among droplet particle size, absorbance and clarity grade of emulsion formed by prescription in the same phase diagram. But, there was no regularity among droplet particle size, absorbance and clarity grade of emulsion formed by prescription in different phase diagram. Conclusion The droplet particle size of emulsion formed by prescription containing the same drugs and excipients in different proportions can be compared by clarity with visual method or absorbance with UV-visible spectrophotometer.