Abstract
This paper presents a study of electrokinetic transport in a nanofluidic chip that allow for separation and preconcentration of the molecular mixtures into a well-aligned multi-wall carbon nano tubes (MWCNTs) array of nanochannels. The MWCNTs array was used as an induced surface charge filter to attract the opposite charged molecules on the wall surface by van der Waals and electrostatic force. The surface charge intensity of MWCNTs is inversely proportional to the channel wall thickness and proportional the dielectric constant of itself with an external electric-field. 1 mM FITC fluorescein and Rhodamine 6G dye mixtures during the electrokinetic trapping process for inducing the surface charges of MWCNTs filter, could be easily to separate by the electric property of dyes in a MCNTs filter nanochannel. For bio-molecules preconcentration process, the concentration capability of 0.5 µM FITC-labeling IgG as high as 10000 folds have been demonstrated.