To Purify A Virus: #NSFCareer Researcher Caryn Heldt

Purifying a virus may sound counterintuitive. But improving virus purification could make vaccines easier to produce and more accessible around the world. Chemical engineer Caryn Heldt's work, funded by #NSFcareer, builds on new theories about virus chemistry to purify or remove them more easily.

  1. Enter the Challenge

  2. Removing viruses is not easy to do. They're small; they're more chemically inert than bacteria and many molecules; they're highly variable in terms of size, shape, and surfaces. But they all share something in common: a new line of virus research suggests that virus surfaces are hydrophobic (water-fearing). That hydrophobicity could help overcome the challenges of virus removal, making them easier to purify.
  3. Meet the Solution

  4. To ease global access to vaccines, we need a solution--literally, a liquid solution of water full of viruses, a smattering of proteins, and some molecules called osmolytes. These, and a porous membrane used for filtration, are the key players in Heldt's research.
  5. Osmolytes can be sugars, proteins, or other molecules. Heldt found in her research that glycine, an amino acid, and mannitol, a sugar, can be used to remove viruses. Here's how:
  6. Osmolytes cause viruses to clump together, or flocculate. “And we if flocculate the viruses then we can use larger pore- size filters to remove them,” she says. Bigger pores = less expensive material = streamlined vaccine production
  7. Cover a Virus or Two

  8. Hydrophobicity helps explain why Heldt's process using osmolytes causes viruses to clump. The next stage of her research will focus on figuring out the specific chemical and physical features of different viruses. While there is a lot of variability of viruses, surface hydrophobicity may be a shared feature.
Read next page