DORSATECH is one of the knowledge based companies that manufactures freeze-dryer.
Freeze drying is the removal of ice or other frozen solvents from a material through the process of sublimation and the removal of bound water molecules through the process of desorption. Sublimation is when a solid changes directly to a vapor without first going through a liquid phase. Thoroughly understanding the concept of sublimation is a key building block to gaining knowledge of freeze drying.
Sublimation in the freeze drying process can be described simply as:
- Freeze: The product is completely frozen, usually in a vial, flask or tray.
- Vacuum: The product is then placed under a deep vacuum, well below the triple point of water.
- Dry: Heat energy is then added to the product causing the ice to sublime.
Lyophilization and freeze drying are terms that are used interchangeably depending on the industry and location where the drying is taking place. Controlled freeze drying keeps the product temperature low enough during the process to avoid changes in the dried product appearance and characteristics. It is an excellent method for preserving a wide variety of heat-sensitive materials such as proteins, microbes, pharmaceuticals, tissues and plasma.