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Jongyoon Han, Ph.D.

Associate Professor
Department of Electrical Engineering and Computer Science
Department of Biological Engineering

Room 36-841
617-253-2290 (phone)

Biosketch

Research Scientist 2001-2002 Sandia National Laboratories, Livermore, CA
Ph.D. Applied Physics 2001 Cornell University, Ithaca, NY
M. S. Physics 1994 Seoul National University, Seoul, Korea
B. S. Physics 1992 Seoul National University, Seoul, Korea

Research Summary

Just as electrical circuits process information in the form of collective motion of electrons that form electrical currents, biological systems transmit and process information mediated by nucleic acids, proteins and small effector molecules. The Han laboratory leverages new advances in microelectromechanical systems (MEMS), microfluidics, and nano- and micro-fabrication to develop new technologies for analyzing complex biological systems.

Nanofluidic Biomolecular Preconcentration and Concentration-Enhanced Assays
Sample preparation is one of the bottlenecks in molecular detection and analysis. During the past decades, significant progress has been made both in binding assays (immunoassays) and mass spectrometry (MS). However, issues related to limited sample capacity and low abundance target create challenges in fully utilizing the power of these new analysis platform. In general, only high-abundance species of a given sample could be detected, while reliable analysis of low-abundance targets is still challenging. To address these problems, our group has sought ways to efficiently concentrate biomolecules in order to enhance the detection sensitivity for both large and small sample volumes. The nanofluidic electrokinetic concentration devices serve as;

  1. Ideal world-to-microchip coupling system: It can collect biomolecules from ~µL fluidic samples (addressable by pipettes) and concentrate them into ~nL plug (addressable by microfluidics).
  2. Generic sensitivity enhancement scheme for many biochemical assays: Wide variety of biochemical assays can be enhanced simply by collecting the reactants and / or target molecules.

Advanced Micro-Nanofluidic Biomolecule / Cell Separation
Bioanalysis is often compared to finding "a needle in a haystack", so the importance of biosample fractionation cannot be exaggerated. Traditionally, Gel electrophoresis, gel-exclusion chromatography and other filtration techniques have been used for bioseparation. In addition to well-known drawbacks such as manual operation, slow separation rate, and need for large equipments, the science behind the molecular sieving and filtration is still yet to be fully clarified. One issue is that most molecular sieves and filters are random nanoporous materials, making it difficult to control / optimize the separation process. In our group, patterned regular sieving structures and nanofilters have been sought as an alternative to conventional separation method: recent developments in micro-nanofluidic sieves and filters have demonstrated superior performance for both analytical and preparative separation of various physiologically relevant macromolecules, including proteins. In addition, recent development in inertial microfluidics and other biomimetic separation techniques (such as cell margination) allow microfluidic cell separation from a complex sample (e.g. raw blood) at very high throughput (~1mL/min), by utilizing physical characteristics of cells (deformability, size, and others).

Selected Publications

  • Bow, H., Pivkin, I., Diez-Silva, M., Goldfless, S.J., Dao, M., Niles, J.C., Suresh, S. & Han, J. A microfabricated deformability-based flow cytometer with application to malaria. Lab on a Chip, 2011, *accepted for publication (*DOI: 10.1039/c0lc00472c).
  • Han Wei Hou, Ali Asgar S. Bhagat, Alvin Guo Lin Chong, Pan Mao, Kevin Shyong Wei Tan, Jongyoon Han, Chwee Teck Lim, "Deformability based cell margination - A simple microfluidic design for malaria infected erythrocyte separation," Lab on a Chip, 2010, 10, 2605 - 2613.
  • Cheow, L. F.; Ko, S. H.; Kim, S. J.; Kang, K. H.; Han, J., “Increase of Sensitivity and Dynamic Range of ELISA using Multiplexed Electrokinetic Concentrator,” Analytical Chemistry, 82, 3383-3388, 2010.
  • Yamada, M., P. Mao, J. Fu, and J. Han, “Rapid quantification of disease-marker proteins using continuous-flow immunoseparation in a nano-sieve fluidic device.” Analytical Chemistry, 81, 7067-7074, 2009.
  • Lee, J.H., B. Cosgrove, A.D. Lauffenburger, and J. Han, “Microfluidic concentration-enhanced cellular kinase activity assay.” Journal of the American Chemical Society, 131, 10340-10341, 2009.
  • Ying-Chih Wang and Jongyoon Han, “Pre-binding dynamic range and sensitivity enhancement for immuno-sensors using nanofluidic preconcentrator,” Lab on a Chip, 8, 392-394, 2008.
  • J. Fu, R. R. Schoch, A. L. Stevens, S. R. Tannenbaum, and J. Han, “Patterned anisotropic nanofluidic sieving structure for continuous-flow separation of DNA and protein,” Nature Nanotechnology, 2, 121-128, 2007.
  • Y.-C. Wang, A. L. Stevens, and J. Han, (2005) "Million-fold Preconcentration of Proteins and Peptides by Nanofluidic Filter," Analytical Chemistry, 77, 4293-4299.

Last Updated: February 7, 2011