Influence of Freezing and Freeze-Drying Parameters on Physical Quality Factors

Additionally, many experimental studies have shown that, for various protein systems, the storage stability improves as the residual humidity decreases and that the optimal final water content is generally around 1% or less. Water contents above the monolayer content increase the mobility of the water that becomes more available for protein degradation reactions with the other solutes of the concentrated phase. Moreover, water is a plasticizer of the amorphous phase that decreases the Tg value, which leads to more difficult storage conditions. Finally, it should be noted that the moisture content is generally not uniform within the vial, the top and the wall zones of the cake being the driest zones and these non-uniformities in the spatial distribution of the water content generally increase with the size of the vial. 

Influence of Freezing and Freeze-Drying Parameters on Physical Quality Factors 

This section is devoted to the discussion and analysis of typical data showing the infiuence of the freezing and freeze-drying parameters on the main physical quality factors encountered during freeze-drying of dmgs. 

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