Electrostretching DNA molecules using polymer-enhanced media within microfabricated devices.
In this paper, we demonstrate immobilization and stretching of single lambda-phage DNA molecules within microfluidic systems using ac fields. We present a novel "thiol-on-gold"-based immobilization technique for fixing one specific end (3' end) of a DNA molecule onto a gold electrode. A polymer-enhanced medium (approximately 3.75 wt % linear polyacrylamide in Tris-HCl) is used to obtain fully stretched configurations (21 microm) of fluorescently stained lambda-DNA molecules. We also present an optimized microelectrode design with pointed electrodes and an electrode spacing of 20 microm for stretching DNA molecules with an ac field (1 MHz, 3 x 10(5) V/m). Finally, using these techniques, we immobilize a single DNA molecule at one electrode edge, stretch the molecule, and fix the other end at an adjacent electrode edge, forming a bridge between two electrodes within a microfabricated device.
Department of Chemical Engineering, The University of Michigan, Ann Arbor 48109-2136, USA.
Vijay
V
Namasivayam
Ronald G
RG
Larson
David T
DT
Burke
Mark A
MA
Burns
D000180:Acrylic Resins; D010582:Bacteriophage lambda / Q000235:genetics; D004247:DNA / Q000032:analysis*; D004279:DNA, Viral / Q000032:analysis; D004553:Electric Conductivity; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D011108:Polymers; D014325:Tromethamine; D000099166:Polyacrylamides
D000180:Acrylic Resins; D004247:DNA; D004279:DNA, Viral; D011108:Polymers; D014325:Tromethamine; D000099166:Polyacrylamides