An Integrated Micro-nanofluidic System for Sample Preparation and Preconcentration of Proteins

In this study, an integrated micro-nanofluidic system for protein analysis was presented. The device is comprised of a micromixer and a preconcentrator with a separation column. The Integrated micromixer based on unbalanced split and cross collision of fluid streams is passive and planar, which is easy to fabricate and integrate to the microfluidic system. The preconcentrator has nanochannels formed by the electrical breakdown of PDMS membrane using high electric shock, without any nano-lithographic process. Micromixer and preconcentrator was used for sample preparation (tagging of protein for detection) and concentration of protein, consecutively. Proteins were electrokinetically trapped near the junction of micro/nanochannels.