(4cw) Non-Linear Electrokinetics and Interfacial Microfluidics: Manipulating Molecules and Organisms on-Demand for Biomedical Science

On-demand manipulation of biological materials from macromolecules to whole organisms is an essential need across many areas in biomedical science. For example, point-of-care liquid biopsy platforms for disease screening can only be made possible if specific molecular biomarkers can be rapidly isolated and quantified from clinical samples. In fundamental biology studies, high-throughput sorting and imaging of cells and model organisms is the key to enable large scale genetic screening and drug development assays. Biological systems are complicated and heterogeneous in nature. Therefore, one of the critical challenges to advance general biomedical science is to develop user-friendly methods that can achieve precise and high-throughput extraction and fractionation of multi-scale biological materials in complex systems, and hence enable multi-dimensional characterization of biological information from molecular to organismal level.

To address this challenge, I have developed a suite of micro-devices for multi-scale biomaterial manipulation using non-linear electrokinetic and interfacial microfluidic principles. During my PhD study at University of Notre Dame, I designed a new generation of electrokinetically-driven ionic circuit devices, including the first-reported ionic memristor and high-flux ionic transistors. This set of devices successfully enables rapid and efficient small nucleic acid (e.g. miRNAs) purification from raw clinical samples, which proves to be highly effective for sample pretreatment and electrochemical sensor integration in liquid biopsy platforms to screen early cancer biomarkers. As a postdoctoral fellow at Georgia Institute of Technology, I further invented a set of integrated microfluidic technologies to enable novel assays in systems biology study using multicellular model organisms, such as nematode Caenorhabditis elegans. By exploiting capillary-driven contact line dynamics on an open-surface micro-hydrogel array, I designed a generalizable microswimmer handling method to achieve ultra-simple, high-throughput isolation and multi-functional screening of complex living organisms. By integrating electrokinetic ionic circuits with a high-density microfluidic array, I developed an electrokinetic-enhanced single-molecular fluorescence in situ hybridization (smFISH) platform, which enables rapid and multiplexed profiling of tissue-specific gene expression patterns in whole animals. I have applied these integrated micro-technologies into the study of key questions in systems neuroscience, such as the underlying mechanism of neurological disease and aging related sensory decline through tissue-specific transcriptional regulations. This suite of micro-devices that I designed requires only minimum equipment and simple operation, and hence can be easily adopted by a broader community of biomedical researchers.

My future research will continue to advance experimental tools and methods for biomedical science with innovative micro-technologies. In particular, I will focus on integrating high-throughput micro-devices and multi-scale biological systems to address the challenge of neurological diseases treatment, prevention, and risk assessment. Building on my previous achievements, I will explore novel physical principles on micro/nanoscale to integrate microfluidic and electrokinetic biomaterial manipulation devices with advanced molecular imaging techniques, and apply these technologies to the use of complex biological systems (e.g. C. elegans, organoids, etc.) both as system-level models to understand neurological diseases and as engineered biosensing materials to assess environmental neurotoxicants and pathogens. I will especially aim to build generalizable and user-friendly methods which can be readily transferred to other scientists, physicians, and field technicians with no additional training. Combining with artificial intelligent-based data analysis tools, I envision my micro-device-based technologies will offer generic platforms and help generate new system-level knowledge that will make a critical impact in neuroscience, healthcare, and environmental studies.

Teaching Interests:

My teaching philosophy is to ignite the students’ passion for learning and understanding engineering fundamentals, to cultivate their critical thinking ability, and to help them transform the fundamental knowledge into unique and practical skillsets. As a graduate instructor and teaching assistant, I have taught core undergraduate Chemical Engineering courses including “Numerical Methods in Chemical Engineering” and “Science of Engineering Materials”. As a co-instructor and guest lecturer, I have taught advanced graduate Chemical Engineering courses including “Microfluidics and Biological Applications” and “Non-Equilibrium Electrokinetics”. I am interested in teaching core Chemical Engineering courses such as “Transport Phenomena”, “Mathematical Methods for Engineers”, “Fluid Mechanics”, “Separation Process”, and “Thermodynamics”. Due to my diverse academic experience in chemical, biological, and electrical engineering, I believe my biggest pedagogical contribution will be to integrate various Bioengineering and Micro-device related courses with chemical engineering fundamentals. For example, I am interested to design advanced and specialized courses such as “Fundamentals in Micro-device Engineering”, “Advanced Technologies for Systems Biology”, and “Integrated Microsystems and Biological Applications”.