Mastitis Shandong Unovet Pharmaceutical Co.,Ltd. , https://www.unovetcn.com
Drying methods are various, such as drying, boiling, drying, spray drying, and vacuum drying, but ordinary drying methods are usually carried out at temperatures above 0 ° C or higher. The products obtained by drying generally have the problems of shrinking size and hardening of the texture. Most of the volatile components are lost, some heat-sensitive substances are denatured and deactivated, and some substances are even oxidized. Therefore, the dried product has a large difference in properties compared with that before drying. The lyophilization method is basically carried out below 0 ° C, that is, in the state where the product is frozen, and only when the residual moisture content of the product is lowered in the later stage, the product is allowed to rise to a temperature above 0 ° C, but generally does not exceed 40 ° C. Under vacuum conditions, when the water vapor is directly sublimated, the drug remains in the frozen ice shelf, forming a sponge-like porous structure, so the volume after drying is almost constant. Before using it again, as soon as you add water for injection, it will dissolve immediately. Freeze dryer Freeze dryer Compared with conventional methods, freeze-drying method has the following advantages:
* Many heat sensitive substances do not degenerate or inactivate. Medical Education Network Collection * When drying at low temperatures, some of the volatile components in the material are lost.
* During the lyophilization process, the growth of microorganisms and the action of enzymes cannot be carried out, so that the original traits can be maintained.
* Since it is dried in a frozen state, the volume is almost constant, and the original structure is maintained, and concentration does not occur.
* Since the moisture in the material exists in the form of ice crystals after pre-freezing, the inorganic salt-soluble substances originally dissolved in water are evenly distributed in the material. When sublimating, the dissolved substances dissolved in water are precipitated, which avoids the phenomenon that the inorganic salt carried by the internal moisture migration to the surface in the general drying method is precipitated on the surface to cause surface hardening.
* The material after drying is porous and spongy. After adding water, it dissolves quickly and completely, and almost immediately restores its original character.
* Since drying is carried out under vacuum, there is very little oxygen, so some easily oxidizable substances are protected.
* Drying can remove 95% to 99% of water, so that the dried product can be preserved for a long time without deterioration.
*Because the material is in a frozen state, the temperature is very low, so the temperature of the heat source for heating is not high, and the heater with normal temperature or low temperature can meet the requirements. If the freezing chamber and the drying chamber are separated, the drying chamber does not need to be insulated, and there is not much heat loss, so the utilization of heat energy is economical.
The so-called lack of perfect technology, the main disadvantage of vacuum freeze drying technology is the high cost. Because it requires vacuum and low temperature conditions, the vacuum freeze dryer is equipped with a vacuum system and a low temperature system, so the investment cost and running cost are relatively high.
The advantage of the freeze dryer
Main: freeze dryer double-layer glass enzyme reactor