Biochemists prolong shelf life for proteins with synthesized polymers

Biochemists have developed a technique to prolong the life-span of proteins by synthesizing polymers to attach to them.

Investigators from the UCLA Department of Chemistry and Biochemistry and the California NanoSystems Institute at UCLA (CNSI) developed the process in order to stabilize proteins during shipping, storage and other activities. The findings suggest that the polymers could also be used in stabilizing protein formulations.

Proteins are often found in drugs, with insulin often being referred to as the best example. They are also widely used in research laboratories, but scientists have often being confronted with their inability to store well and react poorly to fluctuations in temperature.

Therefore, the shipping and storage of proteins must be done in regulated temperatures, which can increase costs dramatically. Often proteins will loose their benefit all together if the 'active' properties are lost.

This is something the researchers from America looked to render, publishing their study in the Journal of the American Society of Chemistry. The researchers found that if they synthesized polymers to attach to proteins you can prolong the life of the drug without using excipients like polyethylene glycol.

The Polymers consist of a polystyrene backbone and side chains of trehalose, which is a disaccharide found various plants and animals that can live for long periods with very little or no water. Trehalose stabilises proteins when water is removed, and is used in the treatment of several conditions such as cancer.

Heather Maynard, a UCLA associate professor of chemistry and biochemistry and a member of the CNSI said: "Our polymers were synthesized by a controlled radical polymerization technique called reversible addition-fragmentation chain transfer (RAFT) polymerization in order to have end groups that can attach to proteins to form what is called a protein-polymer conjugate.

"We found that the polymers significantly stabilized the protein we used -- lysozyme -- better to lyophilization (freeze-drying, in which water is removed from the protein) and to heat than did the protein with no additives."

Posted by Neil Clark