The key points of the freeze-drying process inspection of freeze-drying equipment:
1. Pay attention to whether the freeze-drying process of the product is consistent with the process of registration and approval? Be aware of the following changes affecting the lyophilization process:
1) The situation of product batch enlargement;
2) Product-related changes: container volume, container material, specification and thickness, prescription, supplier of raw and auxiliary materials, etc.;
3) Equipment-related changes: freeze-drying machine, freeze-drying area, number of partition layers, loading method, etc.
2. Pay attention to whether the freeze-drying curve is abnormal (the curve of parameters such as product and/or partition temperature, vacuum degree, condenser temperature and time), and the key process control parameters of the freeze-drying process are (for reference):
1) Pre-freezing stage: pre-freezing rate, pre-freezing minimum temperature, pre-freezing time, condenser cooling time, pre-freezing end time, etc.;
2) Sublimation stage: start heating time, vacuuming time, vacuum degree, etc.;
3) Analysis stage: analysis time, maximum allowable temperature for product heating, pressure control time in the box, maximum vacuum, etc.;
4) Others: total freeze-drying time, etc.
