Ken-ichi Izutsu

TL;DR: The stabilizing effects of various additives against inactivation of an enzyme (β-galactosidase from Aspergillus oryzae) during freeze-drying were studied, with a focus on their crystallinity, and the importance of maintaining the amorphous state of additives used as stabilizing agents during Freeze-Drying is shown.

TL;DR: The stabilizing effect of mannitol during the freeze-drying of proteins was studied using L-lactate dehydrogenase (LDH, rabbit muscle), beta-galactosidase (Escherichia coli) and L-asparaginase (Erwinia chrysanthemi) as model proteins to confirm the importance of maintaining excipients in an amorphous state during freeze-Drying.

TL;DR: Several alternative drying methods are reviewed herein, with particular emphasis on methods that are commonly employed outside of the biopharmaceutical industry including spray drying, convective drying, vacuum drying, microwave drying, and combinations thereof.

TL;DR: The relationship between mannitol crystallization during freeze‐drying and its effects on stabilizing protein structures was studied using lysozyme, bovine serum albumin, ovalbumin, β‐lactoglobulin and lactate dehydrogenase as model proteins to confirm the contribution of molecular interactions between amorphous excipients and proteins to structure stabilization during freeze-drying.

TL;DR: Polymers and sugars prevented dissociation of LDH during the freezing step of lyophilization, resulting in greater recovery of enzyme activity after lyophILization and rehydration, and it is suggested that stabilization during drying results in part from greater inherent stability of the assembled holoenzyme relative to that of the dissociated monomers.