To Purify A Virus

By Allison Mills | Published

A new theory about virus surfaces—that they're hydrophobic—has opened up new processes to improve vaccine production, potentially making them more affordable around the world.

Virus Flocculation

Virus hydrophobicity is the focus of research by Caryn Heldt, an associate professor of chemical engineering, who won a National Science Foundation (NSF) Early Career Award grant. Heldt's CAREER Award will help her explore a process that causes viruses to clump, making them easier to remove.

This is a completely different approach to virus removal. And it builds off a new theory about virus surface chemistry. In her past research, Heldt delved into virus hydrophobicity. That is, how virus surfaces repel water. In the presence of water-loving osmolytes, viruses tend to stick together, making them easier to catch through filtration membranes.

Heldt explains how osmolytes and viruses interact in a solution in her TL;DR video up in the story header (that's too long; didn't read, folks.)

In a nutshell: Basically, viruses are hydrophobic, keeping a layer of water molecules surrounding them at a distance. The osmolytes pull away that layer. Once that happens, those hydrophobic surfaces are attracted to each other, causing the viruses to clump.  Heldt and her team can then catch the virus clumps with larger-pore—and less expensive—screens to remove protein and virus impurities. It's like 

Watch the video below or catch up on the live tweeted chat with Heldt from March.

Live Chat via Storify

Last Modified 11:07 AM, June 8, 2016

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