Chromatographic separations in a nanocapillary under pressure-driven conditions.
We report a unique property of nanocapillaries for chromatographic separations of ionic species. Due to the electric double layer overlap, ions are unevenly distributed inside a nanochannel, with counterions enriched near the wall and co-ions concentrated in the middle of the channel. As a pressure-driven flow is induced, the co-ions will move faster than the counterions. This differential transport results in a chromatographic separation. In this work, we introduce the fundamental mechanism of this separation technology and demonstrate its application for DNA separations. An outstanding feature of this technique is that each separation consumes less than 1 pL sample and generates less than 0.1 nL waste. We also apply this technique for separations of DNA molecules, and efficiencies of more than 1,00000 plates per meter are obtained.
Wang
Xiayan
X
Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, USA.
Kang
Jianzheng
J
Wang
Shili
S
Lu
Joann J
JJ
Liu
Shaorong
S
D002845:Chromatography / Q000379:methods*; D004247:DNA / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification; D008962:Models, Theoretical; D036103:Nanotechnology / Q000379:methods*; D015203:Reproducibility of Results
D004247:DNA