Integrated Nanofluidic Devices and Circuits

The fundamental length scales related to ions and molecules in liquids fall in the range of 1–100 nm. These involves the range of intermolecular forces due to steric interactions, electrostatic forces between charged species, and van der Waals interactions. This talk will focus on how confinement of aqueous solutions in the range of Debye screening length (1–50 nm) in nanochannels can lead to formation of unipolar ionic solutions. The ionic current in such nanochannels is found to several orders of magnitude higher than that predicted by macroscopic theories, and is extremely sensitive to surface charge, which can be used to study surface biomolecular reactions. Furthermore, this phenomenon can be exploited to develop nanofluidic transistors, diodes, and integrated circuits, which is now forming the basis for manipulating and analyzing complex mixtures of biomolecules in ultrasmall volumes.