Technology and principle of improving solubility of Dioscoreae Rhizoma formula granules based on powder modification / 中国中药杂志

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.

Preparation and evaluation of Indigo Naturalis dry suspension based on powder surface modification / 药学学报

A dry suspension of Indigo Naturalis (IN) based on lactose-IN composite particles was designed by powder modification technology to meet the clinical needs of IN. The contact angle was used as an evaluation index to investigate the effects of the type of modifier lactose, the amount of lactose, and the co-grinding time of lactose and IN on the hydrophilicity of IN. The difference between IN before and after modification was compared through physical properties such as particle size and scanning electron microscope, as well as hydrophilic properties such as surface free energy and multiple light scattering. The optimal process of lactose-IN composite particles is as follows: after lactose is ground alone for 2 minutes, it is co-ground with IN at a ratio of 1∶1 for 6 minutes. The results of the investigation of powder properties show that the particle size d0.9 of IN is reduced from 112.75 μm to 87.30 μm after modification. The BET and Langmuir specific surface areas decreased by 8.661 m2·g-1 and 12.512 m2·g-1, respectively. SEM shows that lactose is attached to the surface of modified IN (MIN); surface element analysis shows that Si, Ca, and Mg elements of MIN are smaller than IN, and O elements are larger. The infrared spectrum shows that the MIN possesses the characteristic peaks of both IN and lactose. Compared MIN with IN, the contact angle and the non-polar surface free energy decreased by 35.1° and 9.975 mJ·m-2, respectively; the polar surface free energy and the surface free energy increased by 36.956 and 26.950 mJ·m-2, respectively. The results of multiple light scattering showed that the light transmittance of MIN was 35% lower than that of IN, and the backscattered light intensity was increased by about 25%. Only one excipient was used to successfully prepare IN dry suspension with good wettability and suspending property, which provided a basis for the development of new preparations of IN.