Unraveling the stabilisation of proteins
The technology was presented at the 236th American Chemical Society National Meeting and Exposition.
Current stabilisation techniques freeze-dry the proteins before spraying a thin layer of glass-like sugars over them but the effectiveness of this process can take up to two years to evaluate.
To improve the process researchers have developed a fluorescent probe that they claim can asses the lifetime of hydrogen bonds, and therefore the shelf-life of a protein, within minutes.
Sugar is used stabilise the protein’s molecular structure but the researchers say development of sugar formulations is done by trial and error, with companies having to wait up to two years to evaluate its effectiveness.
Rapidly freezing liquid sugar gives rise to disordered molecules unlike the orderly crystals normally associated with such compounds. In this disorderly form the sugar molecules form hydrogen bonds with the proteins, which are the basis of stability.
As hydrogen bonds degrade the protein’s structure begins to unfold, making them ineffective. Previously pharmaceutical companies had to wait to see how long this degradation took to evaluate whether the sugar coating sufficiently extended the protein’s lifespan.
Implementing the new technology should make it cheaper and easier for pharmaceutical companies to develop proteins that have a long shelf-life at room temperature.
This could increase the availability of proteins in the developing world, where drugs cannot always be refrigerated.
Protein market in rude health
The technology appears to have been developed at the right time to coincide with the rise in demand for proteins. A report by RNCOS predicted that the market would grow from $57bn in 2006 at a compound annual growth rate (CAGR) of 12.83 per cent until 2010.
Double-digit growth was predicted for monoclonal antibodies (mAbs), insulin, interferon beta, G-CSF and coagulation factors.
In addition, the biogenerics market appears set to take off, with a 2005 Business Insights report predicting it would generate sales of $11.2bn by 2010.
This is likely to be driven by sales of erythropoietin, granulocyte colony stimulating factors (g-CSFs), interferon alpha and human growth hormone (hGH).
