At present, ultrafine powder technology is a new type of chemical engineering technology that is more popular in various countries. It began in the 1970s and has a wide range of development prospects in the pharmaceutical industry. Herein, the application of ultra-fine powder technology in Chinese medicine preparations is introduced, and its influence on the quality of pharmaceutical preparations and the technological process are analyzed.

Overview
At present, foreign powders with a particle size of less than 3 μm are called ultrafine powders. Ultrafine powder technology refers to the preparation and use of ultra-fine powders and related technologies. The research includes the preparation, classification, separation, drying, surface modification, particle recombination, particle size measurement, manufacturing and storage of ultrafine powders. In the process of safety technology, ultra-fine powder technology, also known as ultrafine grinding technology, cell-level micro-pulverization technology, which is a purely physical process. It can increase the median particle size of the active and botanical powders obtained from the conventional comminution process from about 75 μm to less than 5 μm to 10 μm. The technology has gradually been widely used in Chinese medicine preparations, especially the use of ultrafine particles of drugs in external medicines, internal medicines and suspension injections to further increase the absorption of drugs in the body and enhance the efficacy of drugs. After the Chinese medicine is micro-pulverized at the cell level, cell disruption can greatly improve the absorption state of the drug and reduce the dose of this drug can still maintain the bio-equivalent, which is of special significance for valuable drugs and resource-poor drug varieties. . Therefore, the introduction of ultra-fine powder technology in the pharmaceutical industry is an inevitable development of traditional Chinese medicine. However, using micropowder technology to micronize the drug will also have a certain influence on the quality of the drug and the technological process of the drug formulation.

Main advantages for traditional Chinese medicine preparations
Helps to improve the bioavailability of drugs
The vast majority of Chinese herbal medicine comes from plants and animals. In general, the medicinal active ingredient is mainly present in the cell, and the active ingredient can only be utilized when the cell is intact without passing through the cell membrane (wall). Ultrafine powder technology can be used to break the wall of herbs. Superfine powder raw materials obtained by ultra-fine powder technology, the broken rate of herbs is greater than 95%, greatly improving the bioavailability and efficacy of drugs. After ultra-fine comminution of traditional Chinese medicines to achieve cell wall breaking of the medicinal materials, the active ingredients in the cells are exposed, so the efficacy is greatly improved and the onset of action is rapid. In particular, for the hard and dense texture of medicinal materials, ultrafine comminution and wall-breaking can eliminate the long process and obstacles of the solvent penetrating the cell wall into the cells and elution of the medicinal components. Therefore, there is a possibility of shortening the extraction time and reducing the dosage.

Helps to improve efficacy
In the process of ultra-fine powder, no overheating phenomenon can be controlled, and at the same time, the smashing speed is faster, which is favorable for the preservation of biologically active components, thereby improving the efficacy.

Helps conserve resources
The use of ordinary mechanical comminution, the more fibrous material will produce a large amount of residue in the crushing process, resulting in the waste of the original medicinal material. The medicinal materials processed by the ultra-fine powder technology can no longer be treated by leaching, which simplifies the extraction process and maximizes the use of the original medicinal materials. Therefore, for some precious herbs and some rare and expensive health-care tonic Chinese medicines, using ultra-fine powder technology to process them into ultra-fine powders can reduce waste of resources and increase the rate of absorption and efficacy.

Effects on quality and process of pharmaceutical preparations
Chinese medicine preparation quality
For quality control of solid formulations, weight differences, blending uniformity, strength of tablets, and more are related to powder operations, while disintegration time, dissolution, and bioavailability are related to the powder properties of various materials in drug formulations. . Due to the characteristics of ultra-fine powder of traditional Chinese medicine, there are still many influencing factors in the process of ultra-fine powder technology. It is still difficult to achieve the same fineness and ultra-fine powder requirements for the same equipment and the same grinding process. In fact, not all drugs are as small as possible, and the optimal particle size of single herbs and compound preparations should be determined through experiments.

crafting process
Because the powder direct compression technology has significant technical advantages and huge economic potential, it has become the focus and trend of the transformation of production lines for pharmaceutical companies, especially foreign large-scale pharmaceutical companies. The biggest obstacle to the widespread application of the powder direct compression technology is the powder control, production efficiency and production line utilization of the raw materials. The micronization of medicinal herbs will bring some unfavorable factors to pharmaceutical operations, such as the flying of dust, the reunion of powder and the problem of fluidity.

Ultrafine comminuted Chinese medicine is not as fine as possible. The physical properties of the powder should be controlled according to customer or process requirements, such as particle size and distribution, specific surface area of ​​the particles, bulk density and compaction density, flowability, and disintegration. Wait.

Ultrafine powder technology features and equipment
In actual industrial production, the crude material is often subjected to coarse comminution and pretreatment by a conventional method. After sieving, further ultrafine comminution is performed to achieve the required particle size specification (classification). The application of the ultra-fine powder technology of Chinese medicine has brought about the innovation and development of the traditional Chinese medicine dosage form, and has broadened the dosage form of raw medicine into medicine.

The key to the ultra-fine crushing process is to determine the proper crushing force field based on the physical properties of the crude drug, so as to select the most effective ultra-fine crushing equipment. At present, the ultra-fine grinding methods for Chinese medicines are mainly mechanical crushing, vibratory crushing, and air-flow crushing. There are many kinds of domestic ultra-fine crushing production equipment sales, including vibratory mills, mechanical shear crushers, cryogenic crushers, and air flow. Crusher, the latter two widely used in the pharmaceutical industry, and the flow crusher and fluidized bed air flow ultrafine crusher is the most widely used.

Superfine mechanical pulverization can be divided into dry pulverization and wet pulverization. According to the principle of crushing force generated in the crushing process, dry pulverization includes air flow, high frequency vibration, rotating ball (rod) grinding, hammering Types and self-grinding and other forms, wet grinding is mainly colloid mill and homogenizer.

Development Trends and Prospects
Modern ultrafine powder technology is a microcosmic combination of drugs, making full use of micronization, compounding, precision, surface modification and particle design technology to achieve the highest level of drugs. In this regard, there is a vast space for research and utilization. The in-depth research and application of this technology will be a new technological growth point and a new economic growth point for Chinese medicine. The progress of foreign countries in microparticles and nanoparticles is very rapid. The emergence of controlled-release drugs is the application of the typical ultra-fine grinding technology. It can broaden the dosage form of crude drugs and can promote the advanced preparation technology in this "raw drug" dosage form. Applications. In short, the application of ultra-fine powder technology in traditional Chinese medicine preparations will enable the development of traditional Chinese medicine into a new stage.

In the continuous development of ultra-fine powder technology, it also encountered this problem: the solubility will not increase infinitely with the decrease of the drug particle size, so the best powder particle size should be determined according to the specific herbs to be better. To give full play to its technological advantages; while solving the problems associated with ultrafine grinding equipment and powder operations, it is necessary to establish and improve the quality evaluation system for pharmaceutical powder particles; the micropowder prepared using ultra-fine powder technology has a large specific surface area and high surface energy. The powder is in a non-steady state, and the principle of ultrafine powder dynamics of drugs remains to be studied. In the future, a systematic study of ultrafine powder technology, quality standards, quantitation, clinical efficacy, safety, and pharmacokinetics should be conducted.

Article selected from: pharmacy monograph
Author: Wang Chunhua

【Collection this page】 【Print this page】 【Close】