ABSTRACT
Freeze drying aka lyophilization is commonly used for chemical and biological pharmaceutical products when a “ready to use” solution product is not feasible due to insufficient stability in solution state. Lyophilization is employed to produce dried powder/cake that can be reconstituted at the point of use. While lyophilization is intended to produce a stable product, the process itself imparts a variety of stresses on the product. The change in scale from laboratory- to pilot- or commercial-scale dryers has an impact on product and, in many cases, requires modifications to the laboratory-scale lyophilization processes. In lyophilization, the size of dryers does indeed matter. While manufacturers of freeze-drying equipment are trying to use the same principles of design when they build large-scale dryers, it is difficult, or economically inefficient, to match the laboratory-scale dryer in ability to quickly adjust process parameters when it is needed.
