Distinguished Medical Engineering Seminar - Tzahi Cohen-Karni

Location: 105 Annenberg Zoom: https://caltech.zoom.us/j/87475595947

My team's efforts are focused on three major thrusts: (i) synthesis and in depth mechanistic investigation of the unique emergent optical, thermal, electrical and electrochemical properties of novel hybrid-nanomaterials and nanomaterials topologies composed on one-dimensional and two-dimensional building blocks, (ii) application and characterization of hybrid-nanomaterials interfaces with cells and tissue, and (iii) development and engineering of nanomaterials-based platforms to interrogate and affect the electrical properties of tissue and cells such as cardiomyocytes, and neurons, with a specific focus to understand electrical signal transduction in complex 3D cellular assemblies. Major questions we strive to answer are: Can we make materials and platforms that are tailored to allow seamless and stable integration with cells and tissue enabling sensing and actuation? Can hybrid-nanomaterials allow new insights about biological processes, e.g., tissue development and disease progression?

In this talk I will describe our recent efforts in tackling these challenges. Our highly flexible bottom-up nanomaterials synthesis capabilities allow us to form unique hybrid-nanomaterials that can be used in various input/output bioelectrical interfaces, i.e., bioelectrical platforms for chemical and physical sensing and actuation. We developed a breakthrough bioelectrical interface, a 3D self-rolled biosensor arrays (3D-SR-BAs) of either active field effect transistors or passive microelectrodes to measure both cardiac and neural spheroids electrophysiology in 3D. This approach enables electrophysiological investigation and monitoring of the complex signal transduction in 3D cellular assemblies toward an organ-on-an-electronic-chip (organ-on-e-chip) platform for tissue maturation investigations and development of drugs for disease treatment. Utilizing graphene, a two-dimensional (2D) atomically thin carbon allotrope, we demonstrated a new technique to simultaneously record the intracellular electrical activity of multiple excitable cells with ultra-microelectrodes that can be as small as the size as an axon ca. 2µm in size. The outstanding electrochemical properties of our hybrid-nanomaterials allowed us to develop electrical sensors and actuators, e.g., sensors to explore the brain chemistry and sensors/actuators that are deployed in a large volumetric muscle loss animal model. Finally, using the unique optical properties of nanocarbons, e.g., graphene-based hybrid-nanomaterials and 2D nanocarbides (MXene), we have formed remote, non-genetic bioelectrical interfaces with excitable cells and modulated cellular and network activity with high precision and low needed energy. In summary, the exceptional synthetic control and flexible assembly of nanomaterials provide powerful tools for fundamental studies and applications in life science and potentially seamlessly merge nanomaterials-based platforms with cells, fusing nonliving and living systems together. https://www.cmu.edu/engineering/materials/people/faculty/bios/cohen-karni.html

Bio

Tzahi Cohen-Karni is an Associate Professor at the Departments of Biomedical Engineering and Materials Science engineering in Carnegie Mellon University, Pittsburgh PA USA. He received both his B.Sc. degree in Materials Engineering and the B.A. degree in Chemistry from the Technion Israel Institute of Technology, Haifa, Israel, in 2004. His M.Sc. degree in Chemistry from Weizmann Institute of Science, Rehovot, Israel, in 2006 and his Ph.D. in Applied Physics from the School of Engineering and Applied Sciences, Harvard University, Cambridge MA, USA, in 2011. He was a Juvenile Diabetes Research Foundation (JDRF) Postdoctoral Fellow at the Massachusetts Institute of Technology and Boston Children's Hospital at the labs of Robert Langer and Daniel S. Kohane from 2011 to 2013. Dr. Cohen-Karni received the 2012 International Union of Pure and Applied Chemistry Young Chemist Award. In 2014, he was awarded the Charles E. Kaufman Foundation Young Investigator Research Award. In 2016, Dr. Cohen-Karni was awarded the NSF CAREER Award. In 2017, Dr. Cohen-Karni was awarded the Cellular and Molecular Bioengineering Rising Star Award, The Office of Naval Research Young Investigator Award and The George Tallman Ladd Research Award. In 2018, Dr. Cohen-Karni was awarded the Cellular and Molecular Bioengineering Young Innovator Award. In 2019, Dr. Cohen-Karni was awarded the Carnegie Institute of Technology (CIT) Dean's Early Career Fellowship.