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Dai X.,Beijing University of Chinese Medicine | Shi X.,Beijing University of Chinese Medicine | Shi X.,Key Laboratory of TCM information Engineer of State Administration of TCM | Shi X.,Beijing Key Laboratory for Basic and Development Research on Chinese Medicine | And 5 more authors.
Journal of Computational and Theoretical Nanoscience | Year: 2014

Ginsenoside Ro (Ro), a natural biosurfactant derived from ginseng, has been proven to form vesicles in aqueous solutions that enhance the solubility of the insoluble compounds. With the intention of expanding the applications of Ro in the pharmaceutical industry, we here examined the influence of drug additives on the solubilization of Ro vesicles. The effects of the compatibility between each drug and the Ro molecules and of the length of the hydrophobic and hydrophilic structure of drug molecules on the solubilizing capacity and solubilization site were here studied using dissipative particle dynamics (DPD). The results showed that the simple hydrophobic drugs lacking hydrophilic groups were mainly located on the hydrophobic layer of the vesicle, and the drugs containing both hydrophobic and hydrophilic structures were located on the palisade layer. There was no single, simple relationship between solubilizing capacity and drug properties. The solubility parameters of the hydrophobic structure, molecular size, changes in hydrophobic and hydrophilic properties attributed to changes in the length of the hydrophobic and hydrophilic structures, and the solubilization site were found to affect the molar solubilization ratio (MSR) of the Ro vesicles. These results provide insight into the vesiclar solubilization system formed by saponin and may serve as guidances for the further development and application of Ro and other saponins.Copyright © 2014 American Scientific Publishers Copyright © 2014 American Scientific Publishers. Source


Dai X.,Capital Medical University | Shi X.,Beijing University of Chinese Medicine | Shi X.,Key Laboratory of TCM information Engineer of State Administration of TCM | Shi X.,Beijing Key Laboratory for Basic and Development Research on Chinese Medicine | And 5 more authors.
Journal of Colloid and Interface Science | Year: 2013

Ginsenoside is an important class of saponin biosurfactant that is derived from ginseng. The interactions between ginsenoside Ro, Rb1, and Rg1 with saikosaponin a (SSa) were explored using multiscale methods. The order of interaction strength was found to be Ro>Rb1>Rg1. Ro markedly increased the solubility of SSa; however, Rb1 could only disperse SSa solid in aqueous medium. No significant interaction was observed between Rg1 and SSa. Ro formed vesicles in aqueous medium while Rb1 and Rg1 formed spherical micelles. The differences in the available surface area of the aggregates appear to have some influence on the interactions between ginsenoside and SSa. However, more important effects are related to their chemical structures and interaction energy. According to the molecular simulation results, glucuronic acid linked to Ro molecules significantly reduced the potential energy through its strong electrical attraction to SSa, which contributed greatly to the strong compatibility between them. The greater number of sugars in Rb1, as compared to Rg1, created more binding sites with SSa, thus resulting in stronger interaction between Rb1 with SSa than between Rg1 and SSa. Spherical and worm-like micelles were found to be formed by Rb1 and SSa molecules. This was different from Ro and SSa, which formed vesicles. The formation of worm-like micelles was through the fusion and modification of small spherical micelles. These results may guide in expanding the applications of ginsenoside. © 2013 Elsevier Inc. Source


Dai X.,Capital Medical University | Shi X.,Beijing University of Chinese Medicine | Shi X.,Key Laboratory of TCM information Engineer of State Administration of TCM | Shi X.,Beijing Key Laboratory for Basic and Development Research on Chinese Medicine | And 4 more authors.
Journal of Colloid and Interface Science | Year: 2012

Ginsenoside Ro (Ro), a natural anionic biosurfactant derived from ginseng, has been found to markedly increase the solubility of saikosaponin a (SSa), which is the active ingredient of Radix Bupleuri. SSa is minimally soluble in water. To determine the mechanism by which Ro solubilizes SSa, the self-assembly behavior of Ro and the phase behavior of blended Ro and SSa systems were studied by mesoscopic dynamics (MesoDyn) and dissipative particle dynamics (DPD) simulations. The simulation results show that Ro can form vesicles via the closure of oblate membranes. At low concentrations, SSa molecules are solubilized in the palisade layer of the Ro vesicles. At high concentrations, they interact with Ro molecules to form mixed vesicles with Ro adsorbing on the surfaces of the vesicles. The evaluation of the SSa solubilization process reveals that, at low concentrations, Ro aggregates preferentially to form vesicles, which then absorb SSa into themselves. However, at high concentrations, SSa first self-aggregates and then dissolves. This is because the solubilization behavior of Ro shifts the precipitation-dissolution equilibrium in the direction of dissolution. These results of the simulations are consistent with those of transmission electron microscopy (TEM) and dynamic light scattering (DLS). © 2012 Elsevier Inc. Source


Pan X.,Beijing University of Chinese Medicine | Pan X.,Beijing Key Laboratory for Basic and Development Research on Chinese Medicine | Pan X.,Key Laboratory of TCM information Engineer of State Administration of TCM | Li F.,Zunyi Medical College | And 14 more authors.
Journal of Near Infrared Spectroscopy | Year: 2015

Near infrared (NIR) diffuse reflectance spectroscopy was investigated to simultaneously determine the particle size (physical attribute) and active ingredient lobetyolin (chemical attribute) of Codonopsis radix. Laser diffraction and high-performance liquid chromatography were used as reference methods to determine particle size and lobetyolin content, respectively. Several spectral pretreatment methods were compared, with first derivative combined with nine-point Savitzky-Golay smoothing filter as the best method for establishing the partial least-squares models of particle size and lobetyolin. Then, synergy interval partial least squares (SiPLS) and backward interval partial least squares (BiPLS) were compared. The results showed that BiPLS was the appropriate method for establishing the particle size model; the root mean square error of calibration (RMSEC), root mean square error of cross-validation (RMSECV) and root mean square error of prediction (RMSEP) values were 34.3 μm, 36.1 μm and 29.2 μm, respectively, and the values of Rcal2, Rcv2 and rpre2 were 0.92, 0.91 and 0.94, respectively. The ratio of performance to deviation (RPD) was 4.1. Meanwhile, SiPLS was the optimal method for establishing the lobetyolin model; the RMSEC, RMSECV, RMSEP values were 0.052 mg g-1, 0.059 mg g-1 and 0.054 mg g-1, respectively, and the values of Rcal2, Rcv2 and rpre2 were 0.87, 0.84 and 0.83, respectively. The RPD was 2.5. According to the variable importance in projection (VIP) scores and the variable selection method of SiPLS, 1210-1296 nm was the second overtone of C-H; 2070-2156 nm and 2242-2328 nm were the combination of C-O, O-H and C-H. Therefore, the results showed that NIR could be used to determine physical and chemical properties simultaneously. © 2015 IM Publications LLP All rights reserved. Source


Wu Z.,Beijing University of Chinese Medicine | Wu Z.,Key Laboratory of TCM information Engineering of State Administration of TCM | Wu Z.,Beijing Key Laboratory for Basic and Development Research on Chinese Medicine | Shi X.,Beijing University of Chinese Medicine | And 8 more authors.
Planta Medica | Year: 2015

The aim of the present study was to demonstrate the reliability of micro-electro-mechanical systems/near-infrared technology by investigating analytical models of two modes of sampling (integrating sphere and fiber optic probe modes) and different sample sets. Baicalin in Yinhuang tablets was used as an example, and the experimental procedure included the optimization of spectral pretreatments, selection of wavelength regions using interval partial least squares, moving window partial least squares, and validation of the method using an accuracy profile. The results demonstrated that models that use the integrating sphere mode are better than those that use fiber optic probe modes. Spectra that use fiber optic probe modes tend to be more susceptible to interference information because the intensity of the incident light on a fiber optic probe mode is significantly weaker than that on an integrating sphere mode. According to the test set validation result of the method parameters, such as accuracy, precision, risk, and linearity, the selection of variables was found to make no significant difference to the performance of the full spectral model. The performance of the models whose sample sets ranged widely in concentration (i.e., 1-4%) was found to be better than that of models whose samples had relatively narrow ranges (i.e., 1-2%). The establishment and validation of this method can be used to clarify the analytical guideline in Chinese herbal medicine about two sampling modes and different sample sets in the micro-electro-mechanical systems/near-infrared technique. © Georg Thieme Verlag KG Stuttgart. Source

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