Nanofabricated quartz cylinders for angular trapping: DNA supercoiling torque detection.

Department of Physics, Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA.
Nature Methods (Impact Factor: 25.95). 04/2007; 4(3):223-5. DOI: 10.1038/nmeth1013
Source: PubMed

ABSTRACT We designed and created nanofabricated quartz cylinders well suited for torque application and detection in an angular optical trap. We made the cylinder axis perpendicular to the extraordinary axis of the quartz crystal and chemically functionalized only one end of each cylinder for attachment to a DNA molecule. We directly measured the torque on a single DNA molecule as it underwent a phase transition from B-form to supercoiled P-form.


Available from: Christopher Deufel, Aug 18, 2014
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