What is the mainstream separation and purification process of traditional Chinese medicine oral liquid?

Traditional Chinese medicine oral liquid has been paid more and more attention in the pharmaceutical industry. At present, dozens of traditional Chinese medicine oral liquids have been listed in China Pharmacopoeia, and the related production technology has been continuously improved. However, most impurity removal procedures still use alcohol precipitation method, centrifugation method and plate-and-frame method.

After extraction and decoction, there are some biological macromolecular impurities with no drug activity, which may affect the quality and stability of the products. Adding ethanol will affect the solubility of these substances and make them precipitate. For example, ethanol can change the dielectric constant of solvent environment, make the hydration of protein and its own conformation change and unfold, affect the interaction between them, and finally lead to aggregation and precipitation. However, the alcohol precipitation method also has some disadvantages, such as the loss or residue of some effective components, which affects the quality of products. Centrifugal or plate-and-frame process has low filtration accuracy, and the products produced are black and rough.

Ceramic membrane is a precision filter element made of inorganic metal oxide materials such as alumina, zirconia and titania, which are sintered at high temperature. The filtration accuracy covers three fields: microfiltration, ultrafiltration and nanofiltration. Ceramic membrane separation technology not only has the functions of filtration, separation and concentration, but also has the characteristics of acid and alkali resistance, high temperature resistance, pollution resistance, easy cleaning, high efficiency, energy saving, environmental protection and simple operation, and has unique application advantages in the field of traditional Chinese medicine preparations.

At present, many manufacturers have used ceramic membrane technology in the production of traditional Chinese medicine preparations. As the impurity removal process of traditional Chinese medicine preparations, ceramic ultrafiltration membrane can effectively remove useless macromolecules such as protein and polysaccharide. In addition, ceramic nanofiltration membrane can also be used as a concentration process to replace the traditional polymer membrane. Because the ceramic membrane has excellent high temperature resistance and is easy to sterilize the equipment, the membrane process section can ensure a sterile environment.