Study on Preparation of Triptolide-glycyrrhetic Acid Compound Microemulsion and Its Physicochemical Properties and in vitro Release Characteristics / 中国药房

OBJECTIVE： To establish content determination method of Triptolide-glycyrrhetic acid compound microemulsion， optimize the formula and investigate its physicochemical properties and release rate in vitro. METHODS： The content of Triptolide- glycyrrhetic acid compound microemulsion was determined by UPLC. The determination was performed on ACQUITY UPLC BEH C18 column with mobile phase consisted of 0.1％ formic acid aqueous solution-acetonitrile （gradient elution） at the flow rate of 0.4 mL/min. The column temperature was 40 ℃. The detection wavelength was set at 218 nm， and sample size was 5 μL. Pseudo-ternary phase diagrams were drawn by water titration method. Using oil phase， surfactants and co-surfactants as index， the formula was optimized， and in intro release characteristics was investigated by in vitro release test. RESULTS： The linear range of triptolide and glycyrrhetinic acid were 1-40 μg/mL（r＝0.999 7） and 10-400 μg/mL（r＝0.999 8）， respectively. The limits of quantitation were 0.5 and 0.8 μg/mL； the limits of detection were 0.1 and 0.2 μg/mL. RSDs of precision， stability and reproducibility tests were all less than 2％. Average recoveries were 100.32％-101.15％ （RSD＝0.36％， n＝6）， 99.78％-101.42％ （RSD＝0.59％，n＝6）. The optimal formula included that medium chain triglyceride as oil phase， polyethylene glycol hydroxy stearate as surfactants， ethanol as co-surfactants， water as water phase， the proportion of them was 8 ∶  28 ∶ 14 ∶ 50. The obtained microemulsion was O/W type， being transparent and clear， with average diameter， average polydispersity index and average viscosity of （62.38±3.44） nm， 0.096±0.001 and （26.84±1.10） mPa·S. Within 24 h， cumulative release rates of triptolide and glycyrrhetinic acid in obtained microemulsion were 99.8％ and 99.7％ （in PBS pH 2.0）， 99.3％ and 99.4％ （in PBS pH 7.4）， 98.9％ and 98.4％ （in PBS pH 9.0）， respectively. Triptolide and glycyrrhetinic acid released faster in the single microemulsion than in the compound microemulsion. CONCLUSIONS： Established content determination method is simple and stable. The optimized formula is stable and feasible. Obtained iriptolide-glycyrrhetinic acid compound microemulsion show better sustained-release effect than sigle microemulsion.

Preparation of resveratrol nanoemulsions and evaluation their pharmacokinetics profiles in rats in vivo / 中草药

Objective :To fabricate resveratrol nanoemulsions and probe their pharmacokinetics profiles in rats in vivo. Methods The nanoemulsions of resveratrol were tailored by using aethylis oleas as the oil phase, Cremophor RH40 as emulsifiers, absolute alcohol as co-emulsifiers, respectively. The formulation was optimized by pseudo-ternary phase diagrams and their physicochemical properties of nanoemulsions were characterized by particle size distribution, transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FTIR). The pharmacokinetics experiments were also performed in rats after gavage and the plasm concentration of resveratrol were determined by HPLC as well as the profiles of pharmacokinetic parameters were obtained by Drug and Statistics (DAS) software. Results: The formula of nanoemulsions were as follows: the ratio of resveratrol-aethylis oleas-mixture surfactant- distilled water was 1:10:24:65. The average particle size diameters of prepared resveratrol nanoemulsions were about 40 nm and the droplets of nanoemulsions were in spherical shape observed by TEM. The results of IR disclosed that the active trans-resveratrol presented in the oil droplet of the nanoemulsions. Compared with resveratrol suspensions, the bioavailability of resveratrol nanoemulsions was increased 1.45-fold, and Cmax reached to 1.93-fold. Conclusion : These results indicated that nanoemulsions may be a promising tool for the delivery of resveratrol.

Effect of solvents on the formation thermodynamics of baicalein-nicotinamide cocrystals / 中国药科大学学报

@#The purpose of this study was to investigate the formation thermodynamics of baicalein(BE)-nicotinamide(NCT)cocrystals in three solvents including ethyl acetate, acetone and trichloromethane. The solubilities of BE, NCT and BE-NCT in the above solvents at 25 °C were measured. Ternary phase diagrams(TPDs)of the BE-NCT-solvent systems were established. The non-linear fitting equation according to 1 ∶1 complexation mechanism of BE-NCT cocrystals demonstrated a good correlation between calculated and experiment data. ΔG0< 0 suggested that BE-NCT cocrystal formation was a spontaneous process. Among the organic solvents studied, the absolute value of ΔG0 in trichloromethane was significantly lower than that in the other two solvents. In addition, the cocrystallization zone in trichloromethane was far away from stoichiometric line. This study provides a theoretical foundation for solvent selection and preparation-condition optimization of BE-NCT cocrystals.

Optimization and Preliminary Evaluation the Formulation of Self-microemulsifying Drug Delivery System of Potassium Dehydroandrographolidi Succinas / 世界科学技术-中医药现代化

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.

Effect of polymers on the formation thermodynamics of adefovir dipifoxil-saccharin cocrystal / 中国药科大学学报

@#The aim of this study was to investigate the effect of polymers on the formation thermodynamics of adefovir dipifoxil(AD)-saccharin(SAC)cocrystal. In the absence and presence of polymers such as polyethylene glycol, ethyl cellulose, polyvinylpyrrolidone and Eudragit E100, solubilities of AD and SAC in ethanol solution containing different concentrations of SAC at variable temperatures were determined by high-performance liquid chromatography(HPLC). Appropriate mathematical model for the description of the influence of polymers and temperature on the solubility of AD-SAC cocrystal was established. The ternary phase diagrams were set up using the assayed solubilities data, and they were used to predict changes of cocrystals solubility and product yield. Addition of polymers resulted in increased solubility of AD-SAC cocrystal, decreased complexation constants(K11), enhanced solubility products(Ksp), but there was a gradually decreased free energy change(ΔG0). The areas of homogeneous liquid phase and pure solid cocrystal in equilibrium with the liquid phase in ternary phase diagrams were also found to be larger. Therefore, although there was no change to the spontaneity of AD-SAC cocrystal formation, there existed retardation to cocrystal formation and reduction in product yield of pure cocrystal in the presence of polymers. Moreover, application of polymers could broaden the concentration range of AD and SAC solutions when solution crystallization was selected to prepare cocrystal.

Relationship between composition and organizational levels of nanostructured systems formed by Oleth 10 and PPG-5-Ceteth-20 for potential drug delivery

In this paper, nanostructured systems were developed, with the aid of ternary phase diagrams, from two surfactants, of differing degrees of lipophilicity (PPG-5-Ceteth-20 and the Oleth 10) and two oil phases (oleic acid and isopropyl myristate). It was observed that there were differences between the four resulting phase diagrams in the physical properties of the systems they represent. Thus, due to the capacity of Oleth 10 (as surfactant) and oleic acid (as the oil phase) to reduce interfacial tension, large regions of translucent systems were seen on the diagrams produced by them. By polarized light microscopy, it was possible to identify the isotropic and anisotropic properties of these systems, which were confirmed by small-angle X-ray scattering (SAXS) analysis. Furthermore, it was found that increasing the proportion of water in the formulations led to more highly organized structures, resulting in narrower and well defined SAXS peaks.

Neste trabalho, os sistemas nanoestruturados com diferentes níveis de organização foram obtidos através dos diagramas de fase ternários, utilizando tensoativos com de diferentes graus de lipofilicidade, o PPG-5-Ceteth-20 e o Oleth 10, e ácido oleico e miristato de isopropila como fases oleosas. Através dos diagramas foi possível observar diferenças significativas relacionadas com as características dos sistemas, devido à capacidade que o Oleth 10 (como tensoativo) e o ácido oleico (como fase oleosa) têm em diminuir a tensão interfacial, facilitando a formação de uma extensa região de sistemas transparentes. Através da microscopia de luz polarizada foi possível identificar as características isotrópicas e anisotrópicas dos sistemas, sendo posteriormente confirmadas pelas curvas de dispersão de raios X de pequeno ângulo (SAXS). Além disso, foi possível verificar que o aumento de água nas formulações proporcionou maior estruturação, permitindo a observação de picos mais estreitos e definidos nas curvas de SAXS.

Preparation of coenzyme Q10 submicron emulsion for intravenous injection and study on its pharmacokinetics in rats / 中国药学杂志

OBJECTIVE: To investigate the O/W submicron emulsion injection formulation, and investigate its pharmacokinetics in the rat. METHODS: Pseudo-ternary phase diagrams were established using the water titration method. The effects of different surfactants, cosurfactants and Km values on the phase diagram were investigated, and the prescription of submicron emulsion formulation was optimized. Stability of coenzyme Q10 submicron emulsion was evaluated, and the pharmacokinetics in the rat after intravenous injection was study. RESULTS: Coenzyme Q10 submicron emulsion consisting of Poloxamer188/Lipoid S100/ethanol/PEG400/water has the lower viscosity, the smaller size and the higher encapsulation efficiency. An obvious sustained-release effect of coenzyme Q10 submicron emulsion was observed after iv injection in the pharmacokinetics experiment, and mean residence time is 6. 55 h. CONCLUSION: The optimized coenzyme Q10 submicron emulsion consumes smaller quantities of auxiliary materials and shows good stability. Moreover, it is easy to manufacture and convenient for clinical use. Copyright 2012 by the Chinese Pharmaceutical Association.