Duke researchers preserve proteins in glassified form

Duke University researchers have devised a method to dry and preserve proteins in a glassified form that seems to retain the molecules' properties as workhorses of biology.

A glassified bead of lysozyme, formed by gently extracting water from a droplet of protein. The dimple at lower right is the 25-micron bead's contact point with a micropipette. | Deborah Rickard, Pratt School of Engineering

They are exploring whether their glassification technique could bring about protein-based drugs that are cheaper to make and easier to deliver than current techniques which render proteins into freeze dried powders to preserve them.

Duke engineer and chemist David Needham describes this glassification process as ''molecular water surgery'' because it removes virtually all the water from around a dissolved protein by almost magically pulling the water into a second solvent.

Turning proteins into glass
''It's like a sponge sucking water off a counter,'' said Needham, a professor of mechanical engineering and materials science at Duke's Pratt School of Engineering, who has formed a company called Biogyali (''gyali'' means glass in Greek) to develop the innovation. That firm has also applied to patent the idea of turning proteins into tiny glass beads at room temperature for drug delivery systems.

A report by Needham, graduate student Deborah Rickard and former graduate student P. Brent Duncan online in the Biophysical Journal describes how his team carefully controlled water removal during glassification by releasing single tiny droplets of water-dissolved protein into the organic solvent decanol with a micropipette.

Preliminary evaluations by his senior scientist David Gaul and a team of undergraduate students showed that four test proteins undergoing such procedures retained all or most of their original activity when water was restored. His group has received about $1 million from the National Institutes of Health grants for the research.