Apr 20th, 1:00 PM - 4:00 PM


Initial Results on the Fabrication of a Dielectrophoretic Trap for DNA Origami

Faculty Sponsor

Dr. Bernard Yurke, Dr. Will Hughes, Dr. Wan Kuang, Dr. Jeunghoon Lee and Dr. Bill Knowlton


The self-assembly properties and small size of DNA suggests that it is an ideal candidate for bottom-up fabrication of nanoscale structures. DNA origami is synthesized when a single strand of DNA is folded and “stapled” into a desired shape via short DNA strands, known as staple strands. One challenge of using DNA as a nanometer scale building material is the controlled positioning of DNA on a substrate. Dielectrophoresis is a method for positioning a polarizable particle in a nonuniform electric field. It has been used to manipulate DNA in specific locations onto a substrate with electron-beam fabricated electrodes.[1] We present ongoing work in which electrodes are being fabricated by a combination of shadow-masked physical vapor deposition (PVD) and electron-beam lithography (EBL) processes. Chromium/gold electrodes are deposited on a silicon wafer through a ceramic shadow mask using PVD. PMMA, an electron-sensitive polymer, is spun-on over the electrodes followed by another deposition of chromium to create a circular electrode on the surface of the PMMA. This electrode is the field forming electrode for the dielectrophoresis process. Finally, EBL is performed to expose small windows over the sites for DNA origami trapping.

[1] Anton Kuzyk,* Bernard Yurke, J. Jussi Toppari, Veikko Linko, and Paivi Torma, Dielectrophoretic Trapping of DNA Origami, Small, Volume 4, Issue 4, April 2008, Pages: 447-450