Loss of vacuum in rubber stoppered vials stored in a liquid nitrogen vapor phase freezer

Freeze-Drying of Biological Materials

“…Pikal (33) has estimated that approximately 63% of the impedance to vapour Row is caused by ADAMS While vials are panicularly convenient for filling and freezedrying, the vial stopper hybrid has the potentlal to leak between the vial neck and stopper (1). The all-glass ampoule theoretically overcomes the potential for leakage since the ampoule tip is heat fused at the end of drying.…”

“…1 illustrates the important component parts of a batch freezedrier. The plant comprises a chamber into which product can be loaded or a manifold onto which flasks containing material may be fastened for processing.…”