Manipulation and overstretching of genes on solid substrates

A molecular chip, i.e., a chip on which single macromolecules are freely arranged, is a key for the fabrication of nanoscopic molecular devices, e.g., DNA molecular array chips. We report on a new method for the manipulation of already deposited single macromolecules, which allows to freely position single polyelectrolytes such as DNA on a substrate, to bend and stretch them, to remove stretching defects, and to overstretch double stranded DNA into two parallel single strands.