Sarah Perry, chemical engineering, recently commented in Chemistry World about efforts to find new ways to deliver nutraceuticals in processed foods. In the Chemistry World article, she said that replacing synthetic surficant emulsifiers with naturally sourced materials would likely be popular with both food companies and consumers.
The Chemistry World story also serves to open a window looking at Perry’s laboratory in the UMass Chemical Engineering Department, mainly because the work covered there is closely related to her own research. In fact, Perry had been the organizer of the American Chemical Society symposium on “Complex Coacervation” that had triggered the Chemistry World article.
According to Perry, “The highlight in Chemistry World centered on work that Qingrong Huang, a Professor in Food Science at Rutgers University presented as part of a special symposium on “Complex Coacervation” at the recent Meeting of the American Chemical Society in Boston that was organized by myself and Paul Dubin from Chemistry. Huang’s research focused on the use of a class of materials known as complex coacervates for the improved delivery and uptake of active ingredients in nutraceuticals. However, coacervates are an extremely diverse class of materials that have found utility in applications ranging from food science to adhesives to drug delivery.”
Perry’s lab is currently working on understanding the self-assembly of coacervate-based materials. She explains that coacervates are a dense, polymer-rich liquid that forms when two oppositely-charged macromolecules interact and form a complex.
As Perry explains, “We are interested in understanding the fundamentals of coacervate formation, and are working specifically on understanding how the arrangement of charges on a polymer affect the self-assembly of our materials. For example, imagine a polymer as a string of beads. Each bead corresponds to a single monomer unit. If half of the beads are charged, there are a variety of different ways in which the beads could be arranged. However, we expect significantly different results if all of the charged beads are clustered together, than if they are spaced out along the entire length of the chain.”
Perry adds that “Looking to biology for inspiration, proteins are effectively polymers where nature has optimized the patterning of different kinds of beads to create different structures and functions. My lab utilizes synthetic polypeptides as model proteins. We synthesize these materials and systematically change the arrangement of the ‘beads’ on our polypeptides and study the effect [that this process] has on the self-assembly and stability of the resultant materials.
Perry’s research team is further investigating how these differently patterned polypeptides interact with various proteins. “While our initial intent is to understand the nature of this interaction,” she says, “our ultimate goal is to develop tunable coacervate-based materials that improve the stability or activity of the encapsulated protein. Earlier this year, we received a grant from the Armstrong Fund for Science to support research related to the development of thermostable tetanus vaccine.”
The coacervate-based research in Perry’s lab is being performed mainly by two of her graduate students, Li-Wei Chang and Yalin Liu, alongside a group of outstanding undergraduate researchers: Kush Basu, Brandon Johnston, Colton Kenny, Drew Knudson, Rasmia Shamsi, and Jon Vélez.
“We also collaborate on this research with Todd Emrick’s group in Polymer Science, Paul Dubin’s group in Chemistry, and Professor Charles Sing from the University of Illinois,” says Perry. (September 2015)