ABSTRACT
Introduction ........................................................................................................ 151
Cryoprotectants and Lyoprotectants .............................................................. 153
Preservation of Proteins ............................................................................ 153
Cryopreservation ............................................................................... 153
Lyophilization..................................................................................... 154
Preservation of Cells and Tissue ............................................................. 155
Molecular Models of Cryo-and Lyoprotectants................................... 158
Conclusions......................................................................................................... 160
Acknowledgment............................................................................................... 161
References ........................................................................................................... 161
Biological systems such as proteins, vaccines (viruses), or cells must often be
stored for extended periods of time by resorting to freezing in solutions of
cryoprotectants. In some cases, it is also possible to freeze-dry (or lyophilize)
such systems in solutions of lyoprotectants, thereby leading to products that
are stable at ambient conditions (Science News, 1995; Wang, 2000; Arakawa
et al., 2001; Brumfiel, 2004). Achieving long-term stability in biological
systems has been a long-standing goal of the food, pharmaceutical, and
biomedical industries. Avoiding the need for refrigeration would reduce
production and storage costs drastically. Development of suitable storage
formulations could increase the availability of labile pharmaceutical
products (e.g., recombinant proteins) in rural areas or third-world countries,
and could facilitate the storage of cells or tissue for subsequent therapeutic
or transplant applications.