Ice-recrystallization inhibiting polymers protect proteins against freeze-stress and enable glycerol-free cryostorage† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c8mh00727f

• Published in: Materials horizons Vol. 6; no. 2; pp. 364 - 368
• Main Authors: Mitchell, Daniel E., Fayter, Alice E. R., Deller, Robert C., Hasan, Muhammad, Gutierrez-Marcos, Jose, Gibson, Matthew I.
• Format: Journal Article
• Language: English
• Published: Royal Society of Chemistry 08.11.2018
• Subjects: Chemistry
• ISSN: 2051-6347; 2051-6355
• DOI: 10.1039/c8mh00727f

Antifreeze-protein mimic polymers are shown to enable solvent-free storage of important proteins for therapy and biotechnology by modulating ice growth. Proteins are ubiquitous in molecular biotechnology, biotechnology and as therapeutics, but there are significant challenges in their storage and distribution, with freezing often required. This is traditionally achieved by the addition of cryoprotective agents such as glycerol (or trehalose) or covalent modification of mutated proteins with cryoprotectants. Here, ice recrystallization inhibiting polymers, inspired by antifreeze proteins, are used synergistically with poly(ethylene glycol) as an alternative to glycerol. The primary mechanism of action appears to be preventing irreversible aggregation due to ice growth. The polymer formulation is successfully used to cryopreserve a range of important proteins including insulin, Taq DNA polymerase and an IgG antibody. The polymers do not require covalent conjugation, nor modification of the protein and are already used in a wide range of biomedical applications, which will facilitate translation to a range of biologics.