(7ao) Complex Fluids in Complex Small Scale Geometries

Scientific Vision

The main thrust of my research is to understand and utilize small scale flow of complex fluids in microfluidic platforms, specially as they arise at the interface of biomedical engineering. Biological complex fluids often contain clinically important biomarkers such as circulating tumor cells, bacteria, tumor derived DNA and exosomes. Microfluidic devices are multiphysics, multiplex systems and comprise various modules and components for detection and measurement of biomarkers. On one hand, microfluidics enables sensitive detection and accurate quantitative measurement of biomarkers dispersed in biological complex fluids, which is appealing from engineering perspective. Further, microfluidics provides tools to gain deeper fundamental insight into properties of complex fluids as carriers of biomarkers. By utilizing video microscopy and image analysis, microfluidics, rheology and computational methods, my engineering strategy is based upon a bottom-up design methodology: I develop innovative microfluidic platforms for bioengineering applications by gaining deeper fundamental insight into properties of complex fluids in the smaller modules comprising the system.

Previous Research Accomplishments

My background and training in fluid dynamics and rheology of complex fluids, computational methods and biomedical microfluidics make me ideally positioned to pioneer research efforts in micro scale flow of complex fluids. After conducting research on rheology of gelation process during my Master of Science studies, I joined Professor Jeffrey Morris’s complex fluid research group at City College of New York. For my doctoral thesis, I focused on fluid mechanics and transport properties of inertial suspensions using computational methods. We contributed to the field of complex fluid rheology by providing in depth details of the relationship between relative particle motion, microstructure and rheological properties of inertial suspensions. We also embarked upon microfluidic flow problems and successfully provided insight into the effect of bulk inertia of the suspension on mass exchange with microfluidic vortices.

My postdoctoral research in Professor Dino Di Carlo’s lab at University of California Los Angeles allowed me to add the microfluidics to my research toolbox. Most importantly, I gained valuable insight into clinical applications of miniaturized flow platforms by conducting research in four main directions: In the first project, I developed efficient microfluidic devices for separation of Circulating Tumor Cells (CTC) from a blood draw by utilizing hydrodynamic force on cancer cells. For the second project, we used microfluidics to self-assemble mammalian cells into ordered trains, followed by encapsulation in droplets. Our efforts in integration of single-phase and multi-phase microfluidics enabled us to study the instability of jets in microfluidic flow focusing geometries in great detail, which further deepened my knowledge of multiphase flow. For the forth project, I combined advanced computational geometry methods, image processing and image analysis with the precision provided by microfluidic droplet generators to gain comprehensive engineering control of tissue generation scaffolds.

Future Research

The central focus of my lab will be on studying the properties and potential applications of complex fluids in engineering applications. In the next 3-5 years, I will focus efforts on the following research items:

1- Microfluidic measurement of cell viscoelastic properties

2- Ordered encapsulation of cells in hydrogel micro-particles

3- Extracorporeal microfluidic for detection and measurement of biomarkers

Teaching Interests:

I believe the purpose of academic education should be training critical thinkers. Solving new problems necessitates the skill of discerning relevant from irrelevant to find the best path to the solution. For being a critical thinker, students need to focus on developing a “toolbox” that includes problem solving, organization, communication, professional integrity and collaboration. This broadens student’s thoughts and helps them avoid mere memorization. The main goal throughout my courses is to help students develop the skill of understanding and reducing the problems down to base principles. For graduate level courses in particular, I will pursue this goal by directing students to work on open-ended questions that reflect more advanced understand- ing of fundamentals.

During my academic career as a graduate student and a postdoctoral research scholar, I gained valuable teaching experience and I look forward to contribute to student education through developing and teaching interesting courses. I am interested and prepared to provide instruction for courses on the following topics, where I would develop a syllabus that includes integration of computational tools. Undergraduate Level: Transport Phenomena, Applied Computational Methods in Science and Engineering, Physics and Applications of Microfluidics and Kinetics of Chemical Reactions; Graduate Level: Advanced Fluid Dynamics, Rheology of Complex Fluids, Applied Microfluidics, Mesoscale Simulation Methods and Applications