High resolution separation by pressure-driven liquid chromatography in meander extended nanochannels

The rapidly developing interest in nanofluidics, which is used to examine liquids on an order that ranges from an attoliter to a femtoliter, correlates with the recent interest in decreased sample amounts, such as in the field of single-cell analysis. In this paper, we have succeeded in the normal phase separation of a 10(1) fL sample with a high number of theoretical plates (10(3) plates), and a fast separation (4 s), using a pressure-driven flow in extended nanochannels. A meander separation channel 1 mu m wide was introduced and showed no band broadening at the turns, unlike microchannels (10(1)-10(2) mu m wide), which is an important aspect in order to lengthen the channel in a space-limited micro/nanofluidic chip. Our device enables the fast separation of an ultra-small volume of sample with a high number of theoretical plates, and will serve as a general platform for the separation of aL to fL volumes of samples. (C) 2012 Elsevier B.V. All rights reserved.