Title:

Process Modeling and Cell Damage Evaluation in Laser-Assisted Living Cell Direct Writing

Speaker:

Dr. Yong Huang

Affiliation:

Dept. of Mechanical Engineering, Clemson University

When:

Tuesday, November 30, 2010 at 10:00:00 AM   Add to Calendar

Where:

MARC Building, Room 114

Host:

Dr. Shreyes Melkote
shreyes.melkote@me.gatech.edu
404-894-8499

Abstract

Maskless jet-based (including laser- and inkjet-based) cell direct writing is a revolutionary advance for printing arbitrary cell patterns as well as for creating heterogeneous three-dimensional living scaffolds cell-by-cell. Most importantly, cell direct writing provides a promising solution to current organ donor shortages by patterning different cells to mimic the cellular organization of native organs, resulting in what is known as organ printing. So far, cell direct-write process-induced thermomechanical damage to cells as well as other biomaterials still poses a significant challenge to ensuring satisfactory post-transfer cell viability. As previous studies show, thermomechanical loading can dramatically increase cell mortality rates during the cell droplet formation and landing processes if direct-write conditions are not properly selected. Using a representative laser-assisted cell direct-write technology (modified laser-induced forward transfer) as a model system, we have been addressing the aforementioned direct writing-induced cell damage challenge by studying 1) the process-induced cell thermomechanical loading profiles during cell droplet formation and landing processes; and 2) the post-transfer cell viability through understanding the correlation between the cell damage/viability and process-induced thermomechanical loading profiles. Living cells are modeled as a special workpiece material with unique material properties in this study. In this talk, modeling of the laser-induced bubble expansion and resultant cell mechanical loading during the cell droplet formation process is first introduced. Then modeling of the cell droplet and hydrogel coating impact and resultant cell mechanical loading during the cell droplet landing process is further discussed. Finally, the relationship between the post-transfer cell damage/viability and the mechanical loading information is captured through a molecular signaling pathway-based modeling approach. It is found that the process-induced cell damage depends on not only the magnitudes of stress, acceleration, and/or shear strain but also the loading history that a cell experiences, and the post-transferred cell viability can be predicted based on the direct-write operating conditions and material properties. It is expected that a complete understanding of process-induced biomaterial damage in such jet-based direct writing will significantly promote safe implementation of biomaterial direct writing for various biomedical applications including organ printing.

Biography

Dr. Yong Huang is an associate professor of Mechanical Engineering and adjunct associate professor of Bioengineering at Clemson University, South Carolina, USA. He received his B.S. degree in Mechatronics Engineering from Xidian University, China, his M.S. degrees in Mechanical Engineering from Zhejiang University, China and the University of Alabama, respectively, and his M.S. in Electrical and Computer Engineering and Ph.D. in Mechanical Engineering from the Georgia Institute of Technology, Georgia. His research interest is to understand material behavior and defect structure in advanced manufacturing/fabrication related to biological systems and energy conversion/storage applications. His current research topics focus on advanced tissue fabrication using laser and nozzle jet, material development and characterization through laser processing and precision machining, and wireless sensor data transmission performance evaluation for process monitoring. He served as the Technical Program Chair for the 2010 American Society of Mechanical Engineers International Manufacturing Science and Engineering Conference (ASME MSEC 2010). He was the recipient of ASME International Symposium on Flexible Automation Young Investigator Award (2008), NSF CAREER Award (2008), SME Outstanding Young Manufacturing Engineer Award (2006), ASME Blackall Machine Tool and Gage Award (2005), and several best paper awards.