Pharmaceutical freeze drying for the preservation of active ingredients
Pharmaceutical freeze drying, also known as lyophilization, is a technique for preserving active ingredients. These pharmaceutical products are preserved by drying, which ensures high and reliable quality for years at room temperature. The process is often used to produce vaccines, antibiotics, enzymes, hormones and various other drugs such as insulin.
In the process, the product is frozen in a phial or vials with a high requirement for homogeneity on a shelf. The homogeneity is achieved via a large mass flow of cryogenic oil over the positioning plates, which reaches down to -63°C. The process step usually takes place at -40°C. After freezing, the inert gases are removed by vacuum pumps and the actual drying starts. The intermediate valve to the ice condenser opens, which usually freezes the free ice molecules at -80°C via a cold surface and enables a deep vacuum. The plates are now heated until the product is completely dry.