Cycle design and optimization
A science-based approach to a better process
In order to ensure a stable product and an elegant cake appearance lyophilization cycles at Coriolis are based on the so-called critical product temperatures of a specific formulation, which should not be exceeded during drying.
These temperatures are the collapse temperature (Tc) and the glass transition temperature of the maximally freeze-concentrated solution (Tg´) and are determined by freeze-drying microscopy (FDM) and differential scanning calorimetry (DSC), respectively. Based on these temperatures appropriate process parameters are chosen.
The following parameters can be defined:
- Freezing rate
- Shelf temperature during freezing
- Duration of the freezing step
- Annealing step (depending on formulation composition)
Primary and secondary drying
- Shelf temperature
- Chamber pressure
- Ramp rate from freezing to primary drying
- Ramp rate from primary to secondary drying
- Duration of primary and secondary drying
- Stoppering pressure
- Type of gas used during stoppering
For cycle optimization key parameters like product temperature (Tp) during drying, shelf temperature (Ts) and chamber pressure (Pc) are monitored and evaluated. In-process controls can be performed by removing samples from the running processes by a sample thief or by individual shelf closure mechanism, which can also be used to generate products of varying residual moisture content in one cycle.
Get in contact with out experts today and find out how we can optimize your lyophilization process.