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ChE Undergrad Hansen Tjo Wins Best Presentation at the Gulf Coast Undergraduate Research Symposium

Hansen Tjo

Hansen Tjo

Chemical Engineering (ChE) undergraduate student Hansen Tjo was recently awarded "Best Presentation” in the Biomolecular Engineering Session at the Gulf Coast Undergraduate Research Symposium, hosted by Rice University. Tjo was also a recent awardee at the 2020 Future Leaders in Chemical Engineering Symposium. Tjo’s GCURS presentation, “Charge Density Rules for Nature-Inspired Materials,” describes research with potential applications in one of the most timely issues in the international news today, the refrigeration of vaccines while they are being transported and stored.

The refrigeration of vaccines is also one theme in the extensive research of Tjo’s adviser, ChE Associate Professor Sarah Perry.

The abstract for Tjo’s presentation explains the context of his research, about which he gave a presentation of approximately 10 minutes at the GCURS event. The stabilization of thermo-responsive biomolecules represents a long-standing engineering problem. “For instance,” as Tjo says, “the effectiveness of vaccine campaigns is limited by the quantities of vaccines that can be transported under refrigerated conditions.”

According to the abstract, in nature, cells store proteins in stress granules through an associative phase separation process termed “complex coacervation,” whereby oppositely charged macro-ions separate into two liquid phases.

“By inducing complex coacervation in both synthetic and biological macromolecular systems, we look to circumvent this need for refrigeration,” as the abstract says. “However, this effort requires extensive analysis of the phase behavior of our proposed materials.”

The abstract adds that “Using polyelectrolyte-micelle complexes, which are ideal phase-separating platforms due to their physicochemical tunability, we seek to extrapolate design principles governing self-assembly in a broad range of coacervate systems.”

As described in the abstract, the authors hypothesize “that the charge densities of both the polymer and micelle phases affect overall phase behavior,” which can be tested through a variety of light-scattering and microscopy experiments geared towards pinpointing critical conditions for phase transitions and understanding how they change as a function of macromolecule charge density.
The ultimate goal of the research is to establish design rules accounting for the effective charge density of each macro-ion to facilitate the tailored design of materials for biomedicine.

The annual GCURS event, which was first held in 2008, is one of the longest-running and most prestigious undergraduate research conferences in the southeast. Open to students from all universities and hosted by Rice University, GCURS provides students around the world the opportunity to present their original research to an audience of their peers.

As the symposium website explains, “GCURS is unique in many ways, but a significant one is that it is not a poster presentation…Participants give 10-to-12-minute oral presentations on their original research or course project. After the presentation, they are coached by faculty and graduate student advisers and receive mentoring and feedback on their presentation skills and their work.” (January 2021)

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