This paper presents a novel method for manipulating single chromosomal DNA, which is intended for the use in highresolution genomic studies. Such operations as translocation, winding and unwinding of single DNA fiber are achieved using optically-driven micro-fabricated structures, including micro-hooks and micro-bobbins for picking-up and winding DNA, with a typical dimension of several μm. The geometry of the laser-manipulated micro-structures is designed in such a way that a spontaneous orientation occurs with its major axis parallel to the laser beam and accepts a DNA fiber. While monitoring under a fluorescence microscope, yeast chromosomal DNA is first extended to the full length by electroosmotic flow. Then the micro-hooks are dispensed in the solution, and a DNA fiber is picked up with the microhook which is driven by a focused laser beam, to separate the targeted DNA from the others. The winding is achieved with a pair of micro-bobbins. The laser is split into two, the first beam being fixed, and the second movable circularly around the first. When the bobbins are made into contact with DNA and revolving motion started, the fiber is wound and suspended between them. The unwinding can be achieved just by reversing the revolving motion.

Date Published: 11 September 2006
PDF: 8 pages
Proc. SPIE 6326, Optical Trapping and Optical Micromanipulation III, 632626 (11 September 2006); doi: 10.1117/12.680190

Published in SPIE Proceedings Vol. 6326:
Optical Trapping and Optical Micromanipulation III
Kishan Dholakia; Gabriel C. Spalding, Editor(s)