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PubMed · 17090091

Blowing DNA bubbles.

N Severin·W Zhuang·C Ecker·A A Kalachev·I M Sokolov·J P Rabe
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Abstract

We report here experimental observations which indicate that topologically or covalently formed polymer loops embedded in an ultrathin liquid film on a solid substrate can be "blown" into circular "bubbles" during scanning force microscopy (SFM) imaging. In particular, supercoiled vector DNA has been unraveled, moved, stretched, and overstretched to two times its B-form length and then torn apart. We attribute the blowing of the DNA bubbles to the interaction of the tapping SFM tip with the ultrathin liquid film.

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DNAMembranes, ArtificialMicroscopy, Atomic ForceNanostructuresParticle SizePolystyrenesSensitivity and SpecificitySurface PropertiesJournal ArticleResearch Support, Non-U.S. Gov't

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N Severin, W Zhuang, C Ecker, A A Kalachev, I M Sokolov, J P Rabe. 2006. Blowing DNA bubbles.. https://doi.org/10.1021/nl061989b

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