Solubility is an important sensory quality attribute of traditional Chinese medicine(TCM) granules. In this paper, 90 batches of granules(30 batches of TCM formula granules, 30 batches of Chinese patent medicine granules and 30 batches of Japanese Kampo granules) were used as the research objects. The turbidity sensor was used to characterize the turbidity curve of the granule dissolution process. The classification system of granule dissolution behaviors was constructed from three dimensions: dissolution degree, equilibrium time, and dissolution mechanism. According to the equilibrium time, the granule dissolution rates were divided into three categories : faster(<100 s), general(101-300 s) and slow(>301 s). According to the turbidity curve profile, the granule dissolution mechanisms were classified into dissolution-controlled type(α-type), dispersion-controlled type(β-type), and dispersion-controlled type followed by dissolution-controlled type(γ-type). The proportion of TCM formula granules, Chinese patent medicine granules and Japanese Kampo granules with complete dissolution or slight turbidity at the end of dissolution was 46.7%, 96.7%, and 10.0%. The proportion of TCM formula granules, Chinese patent medicine granules, and Japanese Kampo granules with faster dissolution rates(<100 s) was 23.3%, 26.7%, and 40.0%. The average dissolution rate of Japanese Kampo granules was faster than that of TCM formula granules, and it was slightly faster than the average dissolution rate of Chinese patent medicine granules. The dissolution mechanism of Chinese patent medicine granules was mainly α-type, while that of Japanese Kampo granules was mainly β-type, and the three types of dissolution mechanisms of TCM formula granules accounted for a relatively average. The purpose of improving the solubility and dispersion of granules can be achieved by combining the comprehensive application of various functional excipients with the small dosage of Japanese Kampo granules and the wide addition scope of excipients. In the process of transforming TCM compound prescriptions into formulas, there is still much room for innovation in formula excipients and process optimization.
Medicine, Chinese Traditional ; Drugs, Chinese Herbal ; Excipients ; Solubility ; Nonprescription Drugs ; Biological Products

The effective components of flavonoids in the "Pueraria lobata-Hovenia dulcis" drug pair have low bioavailability in vivo due to their unstable characteristics. This study used microemulsions with amphoteric carrier properties to solve this problem. The study drew pseudo-ternary phase diagrams through titration compatibility experiments of the oil phase with emulsifiers and co-emulsifiers and screened the prescription composition of blank microemulsions. The study used average particle size and PDI as evaluation indicators, and the central composite design-response surface method(CCD-RSM) was used to optimize the prescription; high-dosage drug-loaded microemulsions were obtained, and their physicochemical properties, appearance, and stability were evaluated. The results showed that when ethyl butyrate was used as the oil phase, polysorbate 80(tween 80) as the surfactant, and anhydrous ethanol as the cosurfactant, the maximum microemulsion area was obtained. When the difference in results was small, K_(m )of 1∶4 was chosen to ensure the safety of the prescription. The prescription composition optimized by the CCD-RSM was ethyl butyrate(16.28%), tween 80(9.59%), and anhydrous ethanol(38.34%). When the dosage reached 3% of the system mass, the total flavonoid microemulsion prepared had a clear and transparent appearance, with average particle size, PDI, and potential of(74.25±1.58)nm, 0.277±0.043, and(-0.08±0.07) mV, respectively. The microemulsion was spherical and evenly distributed under transmission electron microscopy. The centrifugal stability and temperature stability were good, and there was no layering or demulsification phenomenon, which significantly improved the in vitro dissolution of total flavonoids.
Polysorbates/chemistry* ; Flavonoids ; Pueraria ; Surface-Active Agents/chemistry* ; Ethanol ; Emulsions ; Particle Size ; Solubility

To explore the quality consistency evaluation method for multi-component traditional Chinese medicine and establish a dissolution evaluation method suitable for the characteristics of multi-component Chinese patent medicine, this study discussed the characteristics and advantages of the flow-through cell method in the dissolution evaluation of Chinese patent medicine by comparing the impact of the small cup method and the flow-through cell method on the dissolution behavior of water-soluble and lipid-soluble major active components of Danshen Tablets. Dissolution tests were performed using the small cup method as described in the 2020 edition of the Chinese Pharmacopoeia and the newly introduced flow-through cell method(closed-loop method) with water solution containing 0.5% SDS as dissolution medium. Cumulative dissolution curves of the water-soluble component salvianolic acid B and the lipid-soluble component tanshinone Ⅱ_A in Danshen Tablets were plotted, and fitting and similarity analysis of the dissolution models was conducted to identify the characteristics and advantages of the flow-through cell method. For the small cup method, 150 mL of water containing 0.5% SDS was used as the dissolution medium, with a rotation speed of 75 r·min~(-1) and a temperature of(37±0.5) ℃, and 3 mL of samples were taken at 15, 30 min, 1, 2, and 4 h, with fresh dissolution medium added at the same temperature and volume. For the flow-through cell method, a closed-loop system was used. Danshen Tablets were placed in the flow-through cell with approximately 6.7 g of glass beads, and 150 mL of water containing 0.5% SDS was used as the dissolution medium. The flow rate was set at 20 mL·min~(-1), and the temperature and sampling were the same as the small cup method. The results showed that compared with the small cup method, the flow-through cell method had stronger discriminative power and higher sensitivity in distinguishing the dissolution behavior of the two components, and could better reflect the differences in formulation quality, especially for water-insoluble lipid-soluble components. Given that there were no essential differences in the in vitro release kinetics between the two methods, the flow-through cell method could not only replace the traditional small cup method but also better guide the formulation development and identify quality issues of formulations.
Salvia miltiorrhiza ; Medicine, Chinese Traditional ; Tablets ; Water ; Lipids ; Solubility

The poor solubility of insoluble components of traditional Chinese medicine(TCM) is an important factor restricting the development of its preparations. Natural polysaccharides of TCM can be used as functional components to increase the solubility of insoluble components. Epimedium flavonoid secondary glycoside components(EFSGC) have been shown to have positive effects on the prevention and treatment of osteoporosis, but they exhibit poor solubility. Therefore, the strategy of solubilizing EFSGC with TCM polysaccharides was adopted, and its effect on the permeability and stability of EFSGC was evaluated in this study. Based on the equilibrium solubility experiment of EFSGC, it was found that Panax notoginseng crude polysaccharide(PNCP) had the best solubilization effect on EFSGC among the ten kinds of TCM polysaccharides, which increased the solubility of EFSGC from 0.8 mg·mL~(-1) to 13.3 mg·mL~(-1). It should be noted that after the solubilization of EFSGC by preparation technology, the effects on permeability and stability should be considered. Therefore, this study also investigated these two properties. The results showed that PNCP increased the effective transmittance of EFSGC from 50.5% to 71.1%, which could increase the permeability of EFSGC significantly. At the same time, it could improve the stability of EFSGC in the simulated gastric juice environment. In order to explain the solubilization mechanism of PNCP on EGSGC, critical micelle concentration, particle size, potential, differential scanning calorimetry, and infrared spectroscopy were analyzed. It was preliminarily inferred that the mechanism was as follows: PNCP and EFSGC could self-assemble into aggregates for solubilization by intermolecular hydrogen bonding interaction in water. In summary, PNCP can not only improve the solubility of EFSGC but also improve its permeability and stability. This study lays the foundation for the application of TCM polysaccharides as a functional component to solubilize insoluble components.
Medicine, Chinese Traditional ; Flavonoids/chemistry* ; Glycosides ; Epimedium/chemistry* ; Solubility ; Cardiac Glycosides ; Polysaccharides/chemistry*

The powder modification technology was used to improve the powder properties and microstructure of Dioscoreae Rhizoma extract powder, thereby solving the problem of poor solubility of Dioscoreae Rhizoma formula granules. The influence of modifier dosage and grinding time on the solubility of Dioscoreae Rhizoma extract powder was investigated with the solubility as the evaluation index, and the optimal modification process was selected. The particle size, fluidity, specific surface area, and other powder properties of Dioscoreae Rhizoma extract powder before and after modification were compared. At the same time, the changes in the microstructure before and after modification was observed by scanning electron microscope, and the modification principle was explored by combining with multi-light scatterer. The results showed that after adding lactose for powder modification, the solubility of Dioscoreae Rhizoma extract powder was significantly improved. The volume of insoluble substance in the liquid of modified Dioscoreae Rhizoma extract powder obtained by the optimal modification process was reduced from 3.8 mL to 0 mL, and the particles obtained by dry granulation of the modified powder could be completely dissolved within 2 min after being exposed to water, without affecting the content of its indicator components adenosine and allantoin. After modification, the particle size of Dioscoreae Rhizoma extract powder decreased significantly, d_(0.9) decreased from(77.55±4.57) μm to(37.91±0.42) μm, the specific surface area and porosity increased, and the hydrophilicity improved. The main mechanism of improving the solubility of Dioscoreae Rhizoma formula granules was the destruction of the "coating membrane" structure on the surface of starch granules and the dispersion of water-soluble excipients. This study introduced powder modification technology to solve the solubility problem of Dioscoreae Rhizoma formula granules, which provided data support for the improvement of product quality and technical references for the improvement of solubility of other similar varieties.
Powders ; Solubility ; Technology, Pharmaceutical ; Technology ; Plant Extracts ; Particle Size

The present study explored the effect of co-amorphous technology in improving the dissolution rate and stability of silybin based on the puerarin-silybin co-amorphous system prepared by the spray-drying method. Solid-state characterization was carried out by powder X-ray diffraction(PXRD), polarizing microscopy(PLM), Fourier transform infrared spectroscopy(FT-IR), differential scanning calorimetry(DSC), etc. Saturated powder dissolution, intrinsic dissolution rate, moisture absorption, and stability were further investigated. The results showed that puerarin and silybin formed a co-amorphous system at a single glass transition temperature which was higher than that of any crude drug. The intrinsic dissolution rate and supersaturated powder dissolution of silybin in the co-amorphous system were higher than those of the crude drug and amorphous system. The co-amorphous system kept stable for as long as three months under the condition of 40 ℃, 75% relative humidity, which was longer than that of the single amorphous silybin. Therefore, the co-amorphous technology could significantly improve the dissolution and stability of silybin.
Calorimetry, Differential Scanning ; Desiccation ; Drug Compounding/methods* ; Drug Stability ; Silybin ; Solubility ; Spectroscopy, Fourier Transform Infrared ; Technology ; X-Ray Diffraction

This study was designed to explore the potential of gypenosides as a novel natural stabilizer for the production of nanosuspensions. The gypenosides-stabilized quercetin nanosuspensions(QUE-NS) were prepared using the high-speed shearing and high-pressure homogenization method with quercetin as a model drug, followed by their in vitro evaluation.Based on the measured mean particle size and polydispersity index(PDI) of QUE-NS,the single factor experiment was conducted to optimize the preparation process parameters.The freeze-drying method was used to transform QUE-NS into freeze-dried powders, whose storage stability and saturation solubility were then studied.Moreover, the effects of pH and ionic strength on the physical stability of the nanosuspension system were examined.According to the results, the optimized process parameters were listed as follows: shear rate 13 000 r·min~(-1),shear time 2 min, homogenization pressure 100 MPa, and homogenization frequency 12 times.The mean particle size of QUE-NS prepared under the optimum process conditions was(461.9±2.4) nm, and the PDI was 0.059±0.016.During the two months of storage at room temperature, the freeze-dried QUE-NS powders remained stable.The saturation solubility of freeze-dried QUE-NS powders was proved higher than those of quercetin and the physical mixture.The results of stability testing demonstrated that QUE-NS stabilized with gypenosides exhibited good stability within the pH range of 6 to 8,while coalescence was prone to occur in the presence of salt.Overall, gypenosides is expected to become a new natural stabilizer for the preparation of nanosuspensions.
Drug Stability ; Gynostemma ; Nanoparticles ; Particle Size ; Plant Extracts ; Powders ; Quercetin ; Solubility ; Suspensions

The real-time cell-based assay(RTCA) was used to establish the bioelectrical sensing model of Compound Danshen Dripping Pills with rat cardiomyocytes(H9 c2). The time/dose-dependent cell response profiles(TCRPs) of in vitro dissolution and absorption of the pills were determined to establish the continuous dynamic dissolution and absorption kinetic models. Thereby, the cell index(CI)-based dissolution and absorption kinetic curves and kinetic models of Compound Danshen Dripping Pills were obtained. The optimal dissolution kinetic model was Weibull model. The similarity factors f_2 of dissolution curves were greater than 50 and the correlation coefficients of absorption curves were larger than 0.95. With the experiment about the efficacy on mice, percentages of the bleeding time of mice administrated with Compound Danshen Dripping Pills were calculated, and there was a correlation among dissolution, absorption, and efficacy curves(r > 0.9). RTCA is applicable to the study of the dissolution and absorption kinetics of solid compound Chinese medicine preparations. Thus, it is an innovative and feasible method to evaluate the quality and batch consistency of compound Chinese medicine preparations.
Rats ; Mice ; Animals ; Salvia miltiorrhiza ; Solubility ; Drugs, Chinese Herbal ; Myocytes, Cardiac

Because of the complex components, simple content determination can hardly reflect the overall quality of Guizhi Fuling Capsules. Therefore, it is necessary to carry out a multi-component dissolution test. The variability of quality among different batches of products from different manufacturers is a common problem of Chinese medicine solid preparations. To comprehensively control the quality of Guizhi Fuling Capsules, we studied the dissolution behaviors of 7 index components in the capsules under different conditions, and investigated the consistency of dissolution behaviors among different batches of products from the same manufacturer. The basket method of general rule 0931 in Chinese Pharmacopoeia was adopted, and the rotating speeds were set at 50, 75, and 100 r·min~(-1), respectively. The hydrochloric acid solution(pH 1.2), acetate buffer solution(pH 4.0), pure water, and phosphate buffer solution(pH 6.8) were used as the dissolution media. Automatic sampling was carried out at the time points of 5, 10, 20, 30, 45, and 60 min, respectively. The cumulative dissolution of 7 index components was measured through ultra-performance liquid chromatography(UPLC). The difference factor f_1 and similarity factor f_2 were calculated to comprehensively evaluate the similarity of the dissolution curves among 8 batches of Guizhi Fuling Capsules, and a variety of dissolution and release equations were fitted. The results showed that multiple components had faster dissolution rates at higher rotating speed and in hydrochloric acid medium. The 8 batches of Guizhi Fuling capsules showed the average f_1 value lower than 15 and the average f_2 value higher than 50, which indicated that different batches of products had similar dissolution behaviors. Most components had synchronous dissolution behaviors and similar release cha-racteristics. This study provides a reference for the quality consistency evaluation among batches, processing optimization, and dosage form improvement of Guizhi Fuling Capsules.
Capsules ; Wolfiporia ; Solubility ; Hydrochloric Acid ; Drugs, Chinese Herbal/chemistry* ; Chromatography, High Pressure Liquid

To evaluate the effects of Hydroxypropyl methylcellulose acetate succinate(HPMCAS MF) on absorption of silybin(SLB) from supersaturable self-nanoemulsifying drug delivery system which was pre-prepared at the early stage experiment. The cell toxicity of self-emulsifying preparation was evaluated by the MTT method, and the in vitro membrane permeability and absorption promoting effect of the self-emulsifying preparation were evaluated by establishing a Caco-2 cell monolayer model. The in vivo and in vitro supersaturation correlation was evaluated via the blood concentration of SLB. The results of MTT showed that the concentration of the preparation below 2 mg·mL~(-1)(C_(SLB) 100 μg·mL~(-1)) was not toxic to Caco-2 cells, and the addition of polymer had no significant effect on Caco-2 cells viability. As compared with the solution group, the transport results showed that the P_(app)(AP→BL) of the self-emulsifying preparation had a very significant increase; the transport rate of silybin can be reduced by polymer in 0-30 min; however, there was no difference in supersaturated transport between supersaturated SLB self-nanoemulsion drug delivery system(SLB-SSNEDDS) and SLB self-nanoemulsion drug delivery system(SLB-SNEDDS) within 2 hours. As compared with SLB suspension, pharmacokinetic parameters showed that the blood concentration of both SLB-SNEDDS and SLB-SSNEDDS groups were significantly increased, and C_(max) was 5.25 times and 9.69 times respectively of that in SLB suspension group, with a relative bioavailability of 578.45% and 1 139.44% respectively. C_(max) and relative bioavailability of SLB-SSNEDDS were 1.85 times and 197% of those of SLB-SNEDDS, respectively. Therefore, on the one hand, SSNEDDS can increase the solubility of SLB in gastrointestinal tract by maintaining stability of SLB supersaturation state; on the other hand, the osmotic transport process of SLB was regulated through the composition of its preparations, and both of them could jointly promote the transport and absorption of SLB to improve the oral bioavailability of SLB.
Administration, Oral ; Biological Availability ; Caco-2 Cells ; Drug Delivery Systems ; Emulsions ; Humans ; Methylcellulose/analogs & derivatives* ; Nanoparticles ; Particle Size ; Silybin ; Solubility