The Beckman Institute Graduate Student Seminar Series presents the work of outstanding graduate students working in Beckman research groups. The seminars begin at Noon in Beckman Institute Room 1005 and are open to the public. Lunch will be served.
Electrophysiological Approaches to Elucidate Neural Network Dynamics in Microfluidic Platforms
Peripheral spinal sensory neurons transduce sensations of pain, temperature, touch, and proprioception between axonal pathways connecting local sensory environments through the spinal cord to the brain. Recent advances in microfluidic platforms, devices that allow the spatial and temporal control of micro- and nanoliter fluids, provide a unique opportunity to create artificial yet physiological microenvironments in controlled in vitro cultures. However, insights into neural networks formed within microenvironments require new methodologies capable of maintaining low-density neuronal culture, recording electrophysiological signals, and isolating single unit activity. Here we demonstrate the emergence of electrical communication between low-density networks within microenvironments for self-organizing neural networks in microfluidic platforms. The investigation of this inquiry was studied from a unique interdisciplinary neuroengineering research approach, integrating the neuroscience techniques of peripheral sensory neuron culture, bioengineering through microfluidic platforms, and electrical engineering approaches of electrophysiological recording and signal analysis. The conclusions drawn from this study presents future opportunities to further understand localization algorithms and pathologies affecting the neuroelectrical microenvironment surrounding peripheral neurons.
Biography: Amy Maduram is a MD/PhD student in the Neuroscience Program and 2011 Beckman Graduate Fellow. Her research topic is the neuronal microenvironment of dorsal root ganglia neurons in microfluidic platforms, with Dr. Jonathan Sweedler in the Micro and Nanotechology Lab and Beckman Institute.
Linking Electrode Performance with Structure Using X-ray Tomography
Fuel cells have been extensively investigated as alternative power sources due to their high efficiency, high energy density and low emissions; however, significant improvements in electrodes (e.g., reducing cost and improving durability) are still required for widespread use. To make these technological breakthroughs, molecular-level understanding must be transitioned to the rational design of meso- and micro-scale materials and structures and subsequently to high-performance cell- and system-level architectures. To bridge these gaps requires a method of determining structure-activity relationships of complex electrodes as function of component materials choice and synthesis, of electrode fabrication and processing, and of electrochemical environment. X-ray micro-computed tomography (MicroCT) provides material information in multi-scale three-dimensional space with high spatial and temporal resolution, more importantly in a nondestructive fashion which opens up the possibility of simultaneous electrochemical and structural measurements in an operating system.
In this presentation, we will demonstrate the development of structure-activity relationships for electrodes within operating fuel cells. Specifically, we will show how MicroCT allows for qualitative and quantitative analysis of electrode structures (and its durability) as a function of electrode preparation methods. Changes in the physical structure will be correlated to changes in electrode performance and durability. Probing individual electrode structure-activity relationship as a function of preparation protocols and fuel cell operating conditions will eventually lead to more rational design and manufacturing of membrane-electrode assemblies.
Biography: Molly Jhong is a graduate student in the Kenis group at the University of Illinois. She obtained her B.S. and M.S. in chemical engineering from the Tsing Hua University in Taiwan. Her research focuses on investigating the structure-activity relationships of electrodes in electrocatalytic processes, including fuel cells and the electrochemical conversion of CO2 to value-added products.
Detect Dynamic Subcellular Signal at Initiation of Cell Migration
Cell migration is critical for embryonic development, wound healing and cancer metastasis. Protein tyrosine kinase Src plays important roles in cell migration. Therefore, it is important to understand the fundamental mechanism of how Src kinase activity regulates cellular migration and function. Here we present a live cell imaging and analysis system to observe and quantify the coupling between molecular activities and the initiation of migration. This system combines three technologies: micro-pattern, fluorescence resonant energy transfer (FRET)-based biosensor and automated analysis. This system allowed the detection of down-regulation of Src activity coupled with the membrane protrusion at cell front when migration was initiated.
Biography: Yue Zhuo is a Ph.D. student working with Professor Peter Wang in Bioengineering at Illinois. The goal of her research is to understand the fundamental molecular mechanism governing cell migration at subcellular levels. Yue uses fluorescence resonance energy transfer (FRET) sensors to study cell migration and subcellular dynamics under different micro-environment. She is also aiming to develop highly integrative image analysis paradigms which can bridge the fields of fluorescence live cell imaging and quantitative science.