Free Solution Hydrodynamic Separation of DNA Fragments from 75 to 106000 Base Pairs in A Single Run

摘要

We report here a new technique to separate a wide size range ofnDNA fragments in a single run without using polymer gels.nAnalyzing the relative length of DNA fragments is fundamentalnin the field of molecular biology. For the majority of researchnlaboratories, gel electrophoresis [including pulsed field gel electrophoresisn(PFGE)1] is utilized to separate DNA molecules basednon relative size. However, gels can be difficult to work with,nespecially when a narrow capillary or microchannel electrophoresisnis utilized to increase the throughput. Noolandi first proposed anfree solution DNA separation approach2 by tagging DNA moleculesncovalently with a charge-neutral monosized entity or a “drag-tag”nto render the free solution electrophoretic mobilities of the taggednfragments dependent on the fragment size, and Heller et al. werenthe first to have experimentally demonstrated this concept.3 Whilenpromising results were obtained,4 intrinsically the resolution mustndecrease as the fragment size increases. Micro- or nanofabricatednsize-sorting structures have also been proposed for nongel DNAnseparations,5 but resolving power is limited. Chromatographicnmethods for DNA separations6 generally cannot compete with thenresolving power of gel electrophoresis.