Ionic effect on combing of single DNA molecules and observation of their force-induced melting by fluorescence microscopy.
نویسندگان
چکیده
Molecular combing is a powerful and simple method for aligning DNA molecules onto a surface. Using this technique combined with fluorescence microscopy, we observed that the length of lambda-DNA molecules was extended to about 1.6 times their contour length (unextended length, 16.2 microm) by the combing method on hydrophobic polymethylmetacrylate coated surfaces. The effects of sodium and magnesium ions and pH of the DNA solution were investigated. Interestingly, we observed force-induced melting of single DNA molecules.
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عنوان ژورنال:
- The Journal of chemical physics
دوره 121 9 شماره
صفحات -
تاریخ انتشار 2004