Drug freeze-drying includes western medicine and traditional Chinese medicine. China has developed western medicine freeze-drying, and many large pharmaceutical companies have freeze-drying equipment. Freeze-drying technology is widely used in injections, which improves the quality and storage period of drugs and brings benefits to both doctors and patients. There are not many kinds of freeze-dried drugs, the products are expensive and the drying process is not advanced. In terms of Chinese medicine, it is limited to the freeze-drying of a small number of Chinese herbal medicines such as ginseng, velvet antler, yam and cordyceps sinensis, and a large number of Chinese patent medicines have not yet adopted the freeze-drying process, which is far from foreign countries. A few years ago, Japan introduced "western-made Chinese medicine", which changed the decoction method of Chinese medicine, solved the tradition that Chinese medicine could not be made into injections or tablets, and also solved the problem that Chinese medicine could not cure acute diseases. Therefore, the research on freeze-drying technology and products of traditional Chinese medicine is promising.
In the field of biotechnology products, freeze-drying technology is mainly used to produce drugs such as serum, plasma, vaccines, enzymes, antibiotics and hormones. Biochemical test drugs, immunological and bacteriological test drugs; Long-term preservation of blood, bacteria, arteries, bones, skin, cornea, nerve tissue and various organs.
Present situation and development of equipment
The application of freeze-drying technology is inseparable from the equipment. Up to now, the forms of freeze-drying equipment are mainly divided into intermittent and continuous, and the scale of equipment ranges from less than one square meter to dozens of square meters.
Intermittent freeze drying equipment
Intermittent freeze-drying equipment is suitable for multi-variety and small batch production, especially for seasonal food production in the food field. Using single machine operation, if one device fails, it will not affect the normal operation of other devices. Intermittent freeze-drying equipment is convenient to control the requirements of heating temperature and vacuum degree in different stages of material drying. It is easy to process, manufacture and maintain the equipment. However, due to time-consuming operations such as loading and unloading and starting, the utilization rate of equipment is low and the production efficiency is not high.
Continuous freeze-drying equipment
Continuous vacuum freeze-drying equipment has been developed and used at home and abroad. The characteristics of continuous equipment are suitable for producing products with single variety, huge output and sufficient raw materials, especially for producing slurry and granular products. Continuous equipment is easy to realize automatic control, which simplifies manual operation and management. Its main disadvantage is high cost.
With the end of GMP certification, domestic excellent pharmaceutical freeze-drying equipment has entered the modernization stage, with complete functions, reliable work and stable performance. Online cleaning (CIP) or steam sterilization (SIP) can be realized, and all technical indexes can meet the needs of freeze-drying production of biological products and drugs. In contrast, foreign freeze-drying equipment has more varieties and specifications than domestic ones, complete supporting equipment, exquisite energy-saving structure and large output of continuous freeze-drying equipment. In order to ensure the quality and energy saving of freeze-dried products, freeze-drying equipment is often combined with other drying equipment, such as spray freeze-drying equipment.
In the future, how to improve the freeze-drying efficiency, shorten the drying time and save energy on the premise of ensuring the product quality will be the goal of the workers in the freeze-drying industry.