In fall 2019, the Department of Chemical Engineering at the University of Virginia School of Engineering welcomed the second class of Gaden, Gainer and Kirwan fellowship recipients. The Ph.D. students are supported in their first year by an endowment created to fund talented graduate researchers.

Zixian Cui, Asanka Wijerathne and Rhea Braun montage

Gaden Fellow Zixian Cui, Gainer Fellow Asanka Wijerathne and Kirwan Fellow Rhea Braun

Zixian Cui, this year’s Gaden Fellow, earned her B.E. in chemical engineering and technology at East China University of Science and Technology and her M.S. at Carnegie Mellon University. She now works with assistant professor Rachel Letteri engineering the architectures of polymer-peptide conjugates, a new class of soft matter, to promote healing of infected wounds. Polymers — natural or manmade large molecules composed of repeating subunits — are used as carriers for antimicrobial peptides (amino acid compounds) and other therapeutics to reduce dose and improve biocompatibility.

To reduce dose while maintaining efficacy, Cui and Letteri are investigating polymer-peptide conjugates with multiple peptides appended to linear and branched polymers. They anticipate these studies will shed light on how the presentation of antimicrobial peptides on polymer scaffolds relates to antimicrobial performance. Cui is synthesizing the structures and has plans to evaluate their bacteria-killing efficacy in future collaborations with researchers as the UVA School of Medicine.

Developing polymers that can be used in people and animals — referred to as biocompatibility — and combining them with antimicrobial peptides is a novel strategy to combat antibiotic-resistant bacteria. These bacteria, known as multiple drug-resistant pathogens, are among the most serious threats to public health today.

Gainer Fellow Asanka Wijerathne has joined assistant professor Chris Paolucci’s catalysis group, which focuses on computer simulations of chemical reactions using quantum and new hybrid modeling methods across a range of applications. Wijerathne, who received his B.S. in chemical and process engineering at the University of Peradeniya in Sri Lanka, is studying zeolites, a class of natural or synthetic minerals whose properties make them useful as catalysts in industrial applications.

Some types of zeolites can be transformed into specific other types, a process known as interconversion. Wijerathne aims to predict the outcomes of interconversion processes to enable synthesis of zeolites for specific applications. A goal of the research is to reduce the need for costly and often toxic chemical compounds known as organic structure-directing agents currently used in zeolite synthesis.

Rhea Braun is this year’s Kirwan Fellow. A 2019 graduate from Princeton University with a degree in chemical and biological engineering, Braun works in professor Roseanne Ford’s lab researching bacterial chemotaxis. Chemotaxis refers to the movement of bacteria in response to a chemical stimulus. When harnessed, this natural behavior has implications for humans in areas ranging from infectious diseases to removing chemical pollutants from the environment. Braun is studying chemotaxis to understand the fundamental mechanisms that govern bacterial movement.

She is also experimenting with sonification, a new way of characterizing chemotactic behavior that Ford is developing through a recent National Science Foundation award. Bacteria’s erratic swimming motion is notoriously difficult for the human eye to follow under a microscope. Sonification maps their motion in real time to sound, potentially providing researchers another tool to detect patterns in the motion.