(4ga) Engineering Biomaterials for Therapeutic Approaches

As a chemical engineer, I am excited to engineer materials for therapeutical applications. After a valuable experience in industry, I decided to start a Ph.D. program to become a professor to directly mentor the next generation of engineers. During my Ph.D. I have worked on two projects related to bone regeneration and the treatment of ventricular arrhythmias. I plan to complete my degree next summer, and I am interested in a postdoc experience that expands my skills in the biomaterials field.

Research Interests:

I started my M.S. degree working with nanomaterials to purify renewable fuels derived from biomass reforming. I worked with Dr. James Dumesic at the University of Wisconsin – Madison on my thesis, developing gold nanoparticles to selectively oxidized carbon monoxide in hydrogen-rich streams. I used gold nanoparticles and reversible redox compounds to achieve fast and selective reactions in chemically heterogeneous environments. Excitingly, the resulting aqueous solution of reduced compounds can be used to generate power. Alternatively, I developed an electrochemical cell to transfer and store the hydrogen into a liquid carrier that is easier to transport.

After my Master, I transitioned to an industry job applying engineering and scientific principles to manufacturing activities. I worked on the technology transfer of bilayer tablets to deliver a bimodal release of two drugs to treat diabetes. As a result of my technical expertise and contributions, I was appointed as a Product Champion for a Hepatitis C drug product. I was in charge of global technical support and transfer for this franchise drug product with revenues of 1.5 billion dollars in 2016. The most satisfying reward from this experience was that our contributions as engineers resulted in drugs that continue to provide treatments to diabetes patients and save the lives of thousands of Hepatitis C patients.

During my time working at the interface of commercial manufacturing and drug development, I was inspired to pursue a Ph.D. researching biomaterials for therapeutic applications. I joined Dr. Elizabeth Cosgriff-Hernandez’s Lab at The University of Texas, focused on developing biomaterial scaffolds for tissue engineering. The overall goal of my first project was to design a bone graft capable of facilitating bone regeneration in patients recovering from trauma or tumor resection. The lab previously developed a high porosity bone grafts that could be injected to fill irregularly shaped defects. To further improve this platform, I worked on adding a growth factor release to this graft to enhance bone regeneration capabilities. I encapsulated proteins into different porous microspheres and studied the release kinetics. Overall, high loading efficiencies were achieved with a sustained release for 14 days, resulting in a safe and cost-efficient platform.

After my second year as a Ph.D. student, I transitioned to a new project in our lab to develop a treatment for ventricular arrhythmias. The limited efficacy of current therapies inspired this collaborative project with a practicing electrophysiologist, Dr. Mehdi Razavi, at the Texas Heart Institute in Houston. The overall goal is to develop an injectable hydrogel electrode to extend across scarred tissue to prevent arrythmias and defibrillate at lower voltages. To achieve this, I developed a hydrogel precursor solution that will be injected into a cardiac vein and its tributaries to transform them into flexible electrodes that span across the scarred area. The gel cured in situ using redox chemistries and then was connected to a pacing device. We aim to restore proper cardiac pacing using voltages below the pain threshold that current defibrillators use.

In the future, I plan to continue engineering diverse materials for therapeutic applications as an independent investigator. A postdoc experience will allow me to continue getting new skills and techniques to continue engineering hydrogels and other relevant materials for delivering drugs or providing specific cues for new patients' treatments. I am particularly interested in designing new materials that are biocompatible and retain stable electrochemical properties in biological environments for treatment of arrythmias. I am also interested in exploring biomaterials for sustained release and treatment of chronic diseases.

Teaching Interest

Teaching interest

I am interested in teaching courses that cover the diverse experience and training I have received. Some of those courses are Kinetics and Catalysis, Biomaterials (chemistry, properties, characterization, and applications), Materials for Drug Delivery, Introduction to Polymer Science, Pharmaceutical Operations, and Engineering Ethics. I believe in a pedagogical model that aims to maximize each person's potential in the classroom by valuing each contribution and promoting a dialogue that leads to collaboration.

Teaching Experience

I worked as a science and math instructor for two summers in the Upward Bound program serving groups of 15-20 middle school students from low-income families, supporting them to become the first people in their family to enroll and complete a college degree. As part of my work, I designed the curriculum for the summer sessions and prepared the lesson plans. At an undergraduate level, I worked as a Calculus and Chemistry tutor for two years. At the graduate level, I worked as a teaching assistant for the Advanced Kinetics course at University of Wisconsin-Madison.

Mentoring Experience

During my research experience, I have had the opportunity to mentor six undergraduate students. I also participated in a peer mentor program at the Chemical Engineering Department to help new graduate students transition to graduate school. I also served as a mentor for "Proyecto Cumbres" of the Puerto Rico Youth at Risk Organization. In this program, I mentored middle school students at risk of dropping out of school due to a challenging environment.

Outreach

During my Ph.D., I worked in Explain Your Thesis workshops and the Scientist in Residence Program, sharing the exciting discoveries we had made in our research with middle and high school students in the Austin area.

Commitment to Diversity

Diversity of experiences in multiple settings nurture my passion for creating inclusive communities and workplaces. A motivation to become a professor is to help underrepresented students overcome barriers and equip students with the tools to succeed. When I joined my PhD program, there were no support programs for Hispanic or Black engineering graduate students. I led efforts to form a new student organization to create a supportive community among underrepresented minority graduate students at the University of Texas at Austin in collaboration with the Director of the Equal Opportunity of Engineering Office. These efforts led to the creation of the organization Graduates for Underrepresented Minorities, of which I am the current president. We have also established relationships with other student organizations that served URM undergraduates, such as Society of Hispanic Professional Engineers, National Society of Black Engineers, and LGBTQ+ Engineers.

Fellowships:

• Ford Foundation Dissertation Fellowship: National Academy of Sciences, Engineering and Medicine (2021-2022)
• Ford Foundation Pre-Doctoral Fellowship: National Academy of Sciences, Engineering and Medicine (2018 – 2020)
• Thrust 2000 – Leroy H. Cole Endowed Graduate Fellowship in Engineering, The University of Texas at Austin (2016-2021)
• Graduate Engineering Research Scholars (GERS) Fellowship – University of Wisconsin, Madison (2003 – 2005)
• Robert C. Byrd Honors Scholarship (1998-2002)

Awards

• Cockrell School of Engineering Leadership Award: The University of Texas at Austin (2021)
• BMES CMBE Conference Graduate Student Travel Award (2020)
• BMS Employee Award: Employee of the Year - Technical Support Areas BMS (2014)
• Luis Monzón Award - University of Puerto Rico at Mayagüez: Best Chemical Engineering Student of the class (2003)

Publications:

1. Rodriguez-Rivera GJ, Chwatko M, Post A, John M, Buchan S, Waldron C, Razavi M, Cosgriff-Hernandez E, "Transforming coronary veins into flexible pacing electrodes using injectable, ionic hydrogels" (in preparation)
2. Kompella P, Gracia B, LeBlanc L, Engelman S, Kulkarni C, Desai N, June V, March S, Pattengale S, Rodriguez-Rivera G, Woo Ryu S, Strohkendl I, Mandke P, Clark G, "Interactive youth science workshops benefit student participants and graduate student mentors", PLoS Biol (2020)
3. Whitley M.*, Rodriguez-Rivera G.*, Waldron, C., Mohiuddin S., Ceceres S., Sears N., Ray, N., Cosgriff-Hernandez E., "Porous PolyHIPE Microspheres for Controlled Release of BMP-2 from an Injectable Bone Graft", Acta Biomaterialia (2019). (*Authors contributed equally to this work)
4. Rodríguez-Rivera G, Kim WB, Evans, ST, Voitl T, Dumesic J, "Hydrogenation of Benzene Using Aqueous Solution of Polyoxometalates Reduced by CO over Gold Catalysts", Journal of the American Chemical Society 127, 10790 (2005)
5. Kim W, Rodríguez-Rivera G, Voitl T, Einsphar J, Voyles, P , Dumesic J, "Rodríguez-Rivera G, Kim W, Evans, S, Voitl T, Dumesic J, "Catalytic oxidation of CO by aqueous polyoxometalateson carbon – supported gold nanoparticles", Journal of Catalysis 235, 327 (2005)
6. Kim W, Voitl T, Rodríguez-Rivera G, Evans, S, Dumesic J, "Preferential Oxidation of CO in H2 by Aqueous Polyoxometalates over Metal Catalysts", Angewandte Chemie International Edition 44, 778 (2005)
7. Kim W, Voitl T, Rodríguez-Rivera G, Dumesic J, "Powering Fuel Cells with CO via Aqueous Polyoxometalates and Gold Catalysts", Science 305, 1280 (2004)