Protein freeze-dried with trehalose

The Role of Residual Water for the Stability of Protein Freeze-Dried with Trehalose... 

From these arguments, we may conclude that trehalose is the best compromise to maintain an artificial H-bond network that temporarily replaces that developed by H2O molecules and avoids both those catastrophic consequences, that is the formation upon freezing of crystalline ice in that part outside macromolecules that is in contact with liquid water, and the collapse of the structure of membranes or of secondary structures of proteins upon drying due to the escape of H2O molecules. This artificial H-bond network is much less flexible than that established by H2O molecules and considerably slows down the dynamics of H2O molecules (23, 28). It consequently does not allow normal activity. It does not allow life to proceed in the same way as in the H2O network of living conditions. It nevertheless avoids irreversible transformation of the structure of the macromolecule by hydric stress, thus allowing resumption of living activities by rehydration. The discussion that has appeared in the literature to decide which mechanism is the most important, the glass... 

Figure 13 Relationship between kinetics of chemical processes, measured as t versus (T - To) of freeze-dried hGH, formulated with stachyose and trehalose, with protein sugar weight ratios of 1 1, 3 1 and 6 1, at 40 and 50°C. Symbols = chemical deterioration and A = hGH aggregation. Redrawn with changes from M.J. Pikal, private communication of unpublished results...

Figure 7 The effect of var ang concentration of trehalose, while maintaining a constant sugar/protein mass ratio, on recovery of phosphofructokinase (PFK) activity after freeze-drying and rehydration. The protein concentration was adjusted concomitantly with the sugar concentration to maintain a constant sugar/protein mass ratio of 945. (Data taken from Ref. 59.)...

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